[HN Gopher] United B772 at Denver on Feb 20th 2021, engine inlet...
       ___________________________________________________________________
        
       United B772 at Denver on Feb 20th 2021, engine inlet separates from
       engine
        
       Author : haunter
       Score  : 691 points
       Date   : 2021-02-20 22:25 UTC (1 days ago)
        
 (HTM) web link (avherald.com)
 (TXT) w3m dump (avherald.com)
        
       | subhro wrote:
       | No doubt this was a happy ending, but modern airplanes like the
       | 777 are perfectly capable of flying, even climbing with one
       | engine. So, while it seems very heroic on the part of the pilot,
       | it is pretty ordinary and non news.
       | 
       | What I do think is a happy outcome is the debris from the
       | disintegrating engine did not fall on someone and kill/injure
       | them.
       | 
       | Source: Pilot.
        
         | dghlsakjg wrote:
         | Flying on one engine is one thing. Flying one engine while the
         | other is on fire due to unknown causes is another. Still
         | newsworthy in my book.
         | 
         | Source: also a pilot
        
           | subhro wrote:
           | Respectfully disagree. When you are flying with one turbofan,
           | it does not matter why the other engine is on fire. The
           | checklist says, shut off the fuel, if W&B allows, move fuel
           | off the wing and drown the engine in CO2.
           | 
           | Source: Over 3500 hours turbine time.
        
             | dghlsakjg wrote:
             | Im not saying that following the checklist is particularly
             | hard, or the mechanics of what you need to do is outside
             | the skill level of any competent pilot.
             | 
             | I'm saying that practicing engine-outs/fires is
             | psychologically different than bringing a flaming aircraft
             | safely to the ground with several hundred souls on board.
        
       | sadfev wrote:
       | This could have gotten so bad so fast. Well trained pilots, arc,
       | decent protocols and some luck saved 231 lives here!
        
       | infodocket wrote:
       | You can hear the air/ground communications for this flight here
       | via LiveATC.net. The pilots declare an emergency and then a
       | mayday call beginning at 1:15 of the audio.
       | https://forums.liveatc.net/index.php?action=dlattach;topic=1...
        
         | jakear wrote:
         | Curious, I had always heard it should be repeated 3 times, but
         | here they're consistently repeating just twice.
        
           | NikolaeVarius wrote:
           | 3 times is just to "ensure" it gets heard.
        
           | danaliv wrote:
           | You'll find that there's a gap between what the books say
           | about ATC comms and how things are actually done. No one is
           | being pedantic in an emergency.
        
             | [deleted]
        
             | TangoFox wrote:
             | If anyone is curious about what the books say, US Air
             | Traffic Controllers use phraseology prescribed by FAA
             | General Order 7110.65.
             | 
             | Also known as _the 7110_ or _the point sixty-five_ , it
             | includes rules that Air Traffic Controllers must follow to
             | ensure safe and effective operations. So if you're a pilot
             | and are wondering why you have a Hold For Release or are
             | told "unable", you might find the reason in this document.
             | 
             | The Wikipedia article [0] links the PDF version as well as
             | the online version.
             | 
             | [0] https://en.wikipedia.org/wiki/FAA_Order_7110.65
        
               | danaliv wrote:
               | Happy to see a controller here. Thanks for all the
               | clearances. :)
        
           | willyt wrote:
           | It's slightly different for marine radio, where it follows
           | the MIRPDANIO mnemonic you might be thinking of that?
        
         | hnburnsy wrote:
         | EMERGENCY- A distress or an urgency condition.
         | 
         | DISTRESS (MAYDAY)- A condition of being threatened by serious
         | and/or imminent danger and of requiring immediate assistance.
         | 
         | URGENCY (PAN-PAN)- A condition of being concerned about safety
         | and of requiring timely but not immediate assistance; a
         | potential distress condition.
        
           | willyt wrote:
           | "Declaring an emergency" is US specific. The rest of the
           | world doesn't recognise this phrase you have to use either
           | "Mayday" for immediate danger to life or "Pan Pan" for less
           | severe problems. As I understand it, "Declaring an emergency"
           | is the equivalent of a Mayday and the US is very slowly
           | switching away from this non standard phraseology.
        
             | tjohns wrote:
             | "Declaring an emergency" isn't even correct in the US. The
             | FAR/AIM only lists "mayday" and "pan pan". (Yes, it's oddly
             | common here in the US for some reason. I think some pilots
             | are afraid to say the "m" word.)
             | 
             | That said, controllers are human. As long as you get the
             | message across somehow they'll do everything they can to
             | help, even with non-standard phraseology.
             | 
             | Of course, the risk of non-standard phraseology is that you
             | might be misunderstood - especially in countries where
             | English isn't the primary language. It's still good to
             | stick to standard ICAO phraseology whenever possible.
        
               | willyt wrote:
               | For sure, I think in an English speaking country you
               | would probably get your point across. They would most
               | likely come back with asking for confirmation that you
               | are declaring 'mayday', but you would probably cause
               | varying degrees of confusion in many other countries.
               | 
               | I suppose the aim is to make it absolutely clear as
               | quickly as possible that you want ATC to press the big
               | red button labeled 'crash' which sets off the alarms in
               | the airport fire station and causes other controllers to
               | start diverting flights away and telling planes on
               | approach to go around.
               | 
               | These two podcast episodes about the last major crash at
               | Heathrow are pretty interesting if you want to know what
               | happens in ATC during something like this. The fire
               | appliances were already en route before the plane hit the
               | ground. http://airlinepilotguy.com/adam-spink-and-
               | speedbird-38-part-... http://airlinepilotguy.com/adam-
               | spink-and-speedbird-38-part-...
        
         | xvf22 wrote:
         | You can hear the fire alert going off before the mayday.
         | 
         | The fact that they requested a left turn at first it meant the
         | controller knew the right engine was out and they'd need left
         | turns to come in. Always find the level of training impressive
         | and I'm glad they made it back safely.
         | 
         | Aviate, Navigate, Communicate
        
           | msandford wrote:
           | I don't follow how the right engine being out means left
           | turns. Seems like you'd have extra thrust on the left side
           | and you'd want to make right turns. They wanted to keep the
           | right engine high? I'm not sure what I missed.
        
             | xvf22 wrote:
             | When turning into the dead engine, there's a tendency to
             | overbank as the plane will yaw towards the inoperative
             | engine.
        
               | [deleted]
        
             | waiseristy wrote:
             | That's exactly the problem, turning too heavily into the
             | side of the dead engine can introduce a situation where
             | it's impossible to pull out of that turn.
        
             | danaliv wrote:
             | Turning into the live engine is more controllable. When you
             | turn toward the dead engine, the tendency is to turn
             | _more_. You can do it, but it's not as stable.
        
           | pixl97 wrote:
           | Can't wait for the synopsis on the Blancoliro YT channel.
        
         | tialaramex wrote:
         | "Mayday" is the internationally agreed code, so that's one
         | reason to use that - but US accident investigators also noticed
         | a pattern that American pilots are often too reluctant to
         | declare emergency status when it's appropriate as it is here,
         | because they feel it's "not that bad" yet. Having them say it's
         | an emergency without saying "Mayday" is good enough and might
         | mean a few more cases that should have been emergencies are
         | declared as such.
         | 
         | I might look for the link later, but there's an incident with a
         | Youtube reconstruction where a private pilot is nearly out of
         | fuel, the weather is poor, and he's approaching a USAF base en
         | route to his last hope landing site. Airbases are military
         | facilities, closed to civilian traffic. He asks the controller
         | if he can land there. She says he can't... unless it's an
         | emergency.
         | 
         | He should say "Yes, this is an emergency, I'm on fumes here and
         | the weather is much worse than I expected". She'd turn on the
         | airfield's powerful landing lights, and maybe he'd spend the
         | evening explaining his screw up and apologising to a base
         | commander or at worst spend the night in a cell. Nobody dies.
         | Instead he pressed on, and his dire situation only became clear
         | to her when it was too late and he was already doomed.
        
           | lisper wrote:
           | Listening to the audio, the pilot first says, "We've
           | experienced an engine failure, need a turn." ATC does not
           | respond, so he calls again and says "Mayday" in order to
           | unequivocally get their attention.
           | 
           | There are actually two different emergency calls. There is
           | "mayday", and there is "pan-pan", which is a less urgent
           | version of "mayday", but that is hardly ever used.
        
             | hugh-avherald wrote:
             | PAN-PAN is used more often than you might think, at least
             | outside the US. In particular, any medical emergency would
             | be a PAN-PAN.
             | 
             | Here's an interesting example where two aircraft had
             | declared PAN-PAN for quite different reasons, while coming
             | into Sydney. https://www.youtube.com/watch?v=DfidHywKmZI
        
             | donarb wrote:
             | Pan-pan is used for maritime distress calls when a ship is
             | sinking.
        
             | kps wrote:
             | 'Panne' is French for 'breakdown'. (Like 'm'aider' is
             | French for 'help me'.)
        
           | nharada wrote:
           | This one? https://www.youtube.com/watch?v=fLlWf-Fk_YM
           | 
           | Fear of declaring an emergency seems to be fairly common in
           | GA incidents with lower airtime pilots.
        
           | travisjungroth wrote:
           | I landed on a private runway due to bad weather. I saw it was
           | private on the chart but seriously did not care.
           | 
           | It was over a mile long and had landing lights. It was owned
           | by some Texas billionaire brothers who kept their jet there.
           | The people there were actually super nice and loaned us a car
           | to get lunch.
        
           | redis_mlc wrote:
           | Experienced pilots don't mind calling mayday, but:
           | 
           | 1) Often ATC will ask you a lot of distracting questions. It
           | starts with what the problem is and how many souls are on
           | board, but can be lengthy and doesn't solve your problem.
           | 
           | If you listen to the Sully Hudson flight, you can hear how
           | terse Sully is to avoid a conversation with ATC while he's
           | busy flying.
           | 
           | 2) You may be asked for a written letter afterwards, or an
           | investigation may start. Your airline would be interested.
           | 
           | 3) ATC is not responsible for your plane, and cannot fly it
           | for you. Most ATC don't even have an airplane rating.
           | 
           | Pilots have a "get out of jail free card" by filing a NASA
           | report for non-intentional violations. You can search that
           | database.
           | 
           | I filed one once when I was flying an old rental with sketchy
           | navigation equipment into Class B just in case the gauges
           | were out of tolerance.
           | 
           | Source: commerically-rated pilot.
        
       | ThinkBeat wrote:
       | Not long ago, an airplane rained down a few parts near Denver.
       | Today an aircraft has a similar thing happen.
       | 
       | Is it possible that airplanes that have been grounded for a long
       | time thanks to the pandemic have not received the care they
       | should have?
       | 
       | The two aircraft did not have the same cause and I think
       | different parts came lose but one of the results were similar.
       | And somewhat close together
        
         | throwaway189262 wrote:
         | It might be that Denver has more frequent failure. Takeoff
         | power is scaled by temp, altitude, and cargo weight.
         | 
         | Denver is high altitude. And a hub with lots of long range
         | flights. The plane was going to Hawaii. I bet plane was heavy
         | with engines near full power. Most likely time for engine
         | explodey
        
       | just_steve_h wrote:
       | I worked at a Large Internet Infrastructure Company for a long
       | time, and saw software development practices that made my hair
       | curl. All I could think was, "Gee, I'm glad we're not working on
       | aviation software!"
       | 
       | Seriously, though: software "engineering" could actually earn the
       | name, if we had rigorous professional standards, regulatory
       | oversight, and product liability.
        
         | stareatgoats wrote:
         | There have been attempts (the "Keep the Space Shuttle Flying"
         | method):
         | https://github.com/kubernetes/kubernetes/blob/ec2e767e593953...
        
         | Dirlewanger wrote:
         | One thing that sets software apart from other engineering
         | disciplines is that they are grounded in physics (bits running
         | on a semiconductor doesn't matter for this discussion) and have
         | been around (in some form) for thousands of years. How do we
         | know if a design is sound? We can check it by doing the math.
         | How do we know if a program is sound (what does that even mean?
         | There's our first problem)? Well, we rely on a large compendium
         | of heuristics that are based on nothing but experiences
         | compiled over the past ~60 years. Also, that compendium is
         | constantly being added to. Also, virtually everyone disagrees
         | on what should/shouldn't be in this compendium.
        
           | just_steve_h wrote:
           | I'm wading into waters that are way over my head here, but my
           | understanding is that it is possible for software to be
           | provably correct, in the mathematical sense of "proof."
           | 
           | I'm well aware of the admixture of folklore, experience, and
           | caffeine-fueled inspiration that constitutes much of the
           | software that runs our world.
        
             | vvanders wrote:
             | Have a peek a metastability[1], any time a digital system
             | crosses a clock domain there's basically statistics making
             | sure the whole thing doesn't fall over.
             | 
             | From need a better MTBF? Throw a couple more inline flip-
             | flops.
             | 
             | [1]
             | https://en.m.wikipedia.org/wiki/Metastability_(electronics)
        
             | ghaff wrote:
             | There's work going on in formal verification but it has
             | many limitations.
             | 
             | I'd also point out that in MechE/CivE fields, you're still
             | dependent on materials (and maintenance) working as
             | advertised. It's also often the case that operating
             | conditions just end up being different from what was
             | designed for or certain failure modes weren't considered.
             | See, e.g. the Citibank Building in NYC http://www.slate.com
             | /blogs/the_eye/2014/04/17/the_citicorp_t...
        
             | Dirlewanger wrote:
             | I think being able to prove that a program can be correct
             | is getting close to P=NP territory.
        
               | Raptor22 wrote:
               | It's very difficult but there have been strides in that
               | direction: http://web1.cs.columbia.edu/~junfeng/09fa-e699
               | 8/papers/sel4....
        
               | aklein wrote:
               | Cannot prove some program is correct, in general, because
               | that's effectively the halting problem. But in practice
               | it is sufficient to enforce (prove) the absence of
               | behaviors via constraints like types or contracts.
        
             | rocqua wrote:
             | It is possible to prove software adheres to a certain
             | specification. This is time consuming, and how feasible it
             | is depends a lot on how your specification was written. It
             | generally also depends on how your software was written.
             | 
             | The big issue is that writing a useful specification can be
             | hard. Especially if you want to also make the specification
             | easy to check.
             | 
             | A side issue is that your proof will make assumptions about
             | how a computer works that are simplified.
        
             | archi42 wrote:
             | Source: I work on static analyzers, so I'm biased to that.
             | 
             | We can not prove _every_ thing, as others pointed out the
             | fundamental issue here is the "halting problem". However,
             | this doesn't mean we can't prove _any_ thing. Wikipedia
             | says:
             | 
             | > In computability theory, Rice's theorem states that all
             | non-trivial, semantic properties of programs are
             | undecidable.
             | 
             | I often feel like the "trick" is to push the trivial stuff
             | to be as useful as possible. You can work from several
             | vectors: 1. You build better static analyzers (difficult
             | and computationally expensive the further you push it - but
             | that's what we're doing) 2. reduce the complexity of the
             | "analyzed thing" (high level language, assembly,...) to
             | allow for easier analysis, while still being useful (a
             | assembly language only supporting 'nop' is trivial to
             | analyze, but pretty useless overall; otoh you can disallow
             | some constructs in C to make the language easier to
             | analyze).
             | 
             | There are of course other forms of "provably correct". E.g.
             | programming in a language that has proofs attached to it,
             | like coq [which is the name of a proof assistant].
             | Disclaimer: I've never used coq myself, but know plenty who
             | do. I think that's something that might interest you. [And
             | thanks to the genius who christened that tool: No,
             | seriously, I'm not trying to be rude!]
             | 
             | [edit] Didn't check that link, but maybe you find it
             | interesting https://www.cs.princeton.edu/courses/archive/sp
             | ring13/cos510... There are of course other approaches than
             | coq, e.g. Isabelle is often mentioned. See the "See also"
             | on https://en.wikipedia.org/wiki/Coq
        
             | bluGill wrote:
             | You can, but first we need to figure out what correct is in
             | the first place. I can prove hello world doesn't overflow
             | buffers, but it is a bit harder to prove that my font
             | renders the letters vs some random scribbles.
        
         | hu3 wrote:
         | General software requirements can change drastically in a short
         | period. Heck one of our clients requested major parts of our
         | solution to be rebuilt for the third time within 6 months to
         | accommodate the whims of their new leadership.
         | 
         | You don't see that happening with aviation software where
         | requirements are set in stone.
        
           | starpilot wrote:
           | So raise the price of the software so that you can afford
           | more/better software engineers, to produce a more robust and
           | flexible project. Then it'll be aerospace quality, aerospace
           | costs.
        
             | hu3 wrote:
             | So your solution is to charge more and throw more engineers
             | at the problem? Sounds like one of my ex-bosses.
             | 
             | Apple does that and they couldn't be further apart from
             | aerospace engineering quality. Their software and hardware
             | has been historically littered with problems and bugs.
        
         | da_big_ghey wrote:
         | Exists for these reasons secure coding standards, MISRA and
         | BARR and others. If we had same restrictions as other
         | engineering profession maybe we still use COBOL. In important
         | places with big safety concern we follow better guidelines, in
         | webshit front end are do more, not so much concern with a
         | mistaking. This is the best way, the allow of breaking in
         | unimportant but make rule in important.
        
         | starpilot wrote:
         | You just don't need that in software when most of the industry
         | is low consequence. It's only losing money at most tech
         | companies, not killing your coworkers. This hasn't happened to
         | me personally, but it's not cool when Rob the test pilot, whose
         | family you've hung out with and that you've gone on hikes with,
         | literally dies next day in a fiery crash. But that's the risk
         | any test pilot accepts.
        
           | just_steve_h wrote:
           | That's the excuse I keep heading. Then, I find out that the
           | "low consequence" software I've worked on is being relied
           | upon in very consequential contexts.
           | 
           | Can I tell your customers that the software you're selling
           | them is only built for "low consequence" applications?
        
       | dkdk8283 wrote:
       | > The aircraft returned to Denver for a safe landing on runway 26
       | about 23 minutes after departure. The aircraft stopped on the
       | runway for a check by emergency services. Emergency services
       | advised of an active fire within the right hand engine and
       | extinguished the fire a few minutes later.
        
       | integrate-this wrote:
       | I'm starting to feel bad for Boeing.
        
       | cracker_jacks wrote:
       | Wake up, Donnie.
        
         | mat_0 wrote:
         | =:p (Ascii is hard)
        
       | just_steve_h wrote:
       | Simon (the founder & proprietor of The Aviation Herald) is an
       | incredible force for good in the world. His work on that site,
       | for well over a decade now, is legendary.
        
         | hu3 wrote:
         | Fun fact: the response header [1] of that website suggests it
         | is powered by Apache and Perl. Which is amazing in itself. And
         | it's still responsive despite being #1 on HN.
         | 
         | [1] Apache/2.2.17 (Unix) mod_ssl/2.2.17 OpenSSL/1.0.2r
         | mod_perl/2.0.4 Perl/v5.10.0
        
           | tantalor wrote:
           | Why is that suprising? Serving static content is easy
        
             | EvangelicalPig wrote:
             | I mean. How much is classic Perl used in web applications
             | these days?
        
               | tantalor wrote:
               | 0.1%, not much!
               | 
               | https://w3techs.com/technologies/overview/programming_lan
               | gua...
               | 
               | But concatenating strings together is the same in any
               | language, right?
        
             | rossdavidh wrote:
             | ...and yet, very rarely done. That the correct technology
             | for a news site (static content) was done, is the
             | surprising part.
        
               | dirkt wrote:
               | It would also be the correct technology for most sites -
               | you don't need fancy Javascript for just the contents.
               | 
               | Navigation, ads, etc., maybe, but not the contents
               | itself. Most webpages could be perfectly useful with
               | Javascript completely disabled.
               | 
               | Sadly, many aren't.
        
               | tantalor wrote:
               | Fancy JavaScript has nothing to do with serving static
               | content. JavaScript itself is (or should be) static
               | content anyway.
               | 
               | If you're talking about using JS to load content on page
               | load, for whatever reason, that async content can also be
               | static. For example some sites use the URL fragment (hash
               | parameter) to load content, but the server does not
               | receive this:
               | 
               |  _The fragment identifier functions differently to the
               | rest of the URI: its processing is exclusively client-
               | sided with no participation from the web server_ -
               | https://en.wikipedia.org/wiki/URI_fragment
        
       | ortusdux wrote:
       | I have wondered in the past if the benefits of a 'jettison
       | damaged engine' feature would outweigh the risks.
        
         | londons_explore wrote:
         | I suspect most airframes dont have sufficient spare strength to
         | handle the imbalanced forces of an engine on one wing but not
         | the other during flight.
        
           | [deleted]
        
         | just_steve_h wrote:
         | It's unclear what benefit there would be. On the other hand,
         | instantly changing the balance of the aircraft by jettisoning a
         | large mass from one wing would almost certainly make the
         | aircraft uncontrollable.
         | 
         | An American Airlines DC-10 crashed after takeoff from Chicago
         | in 1979 (?), after one engine separated from the wing. At the
         | time, it was the deadliest crash in the US.
        
           | danaliv wrote:
           | The loss of control in that accident was caused by slat
           | asymmetry. Removing an engine, by itself, wouldn't be enough
           | to induce loss of control.
        
         | danaliv wrote:
         | I'm trying to imagine a scenario where that would be
         | beneficial. Maybe uncommanded thrust reverser deployment.
         | Although I think in that case it's likely to "self-jettison"
         | anyway!
        
         | geff82 wrote:
         | Pilot here. You always want to keep the engine for the reason
         | of weight and balance and aerodynamical integrity.
        
         | yread wrote:
         | They are mounted using shear pins - so if they somehow
         | malfunction so much that they would break the wing, they fall
         | off instead. Self-jettisoning if you want. Here are some
         | examples
         | 
         | https://aviation.stackexchange.com/questions/24935/have-jet-...
        
         | eeZah7Ux wrote:
         | The dangerous bit is the fuel - and that can be cut off from
         | the engine and/or jettisoned.
        
       | haunter wrote:
       | Recording of the ATC
       | https://twitter.com/ryancaustin1/status/1363236118657957895?...
       | 
       | Video of the flying debris
       | https://twitter.com/jacdecnew/status/1363241028690599938?s=2...
        
         | throw0101a wrote:
         | Animated recreation with audio:
         | 
         | * https://www.youtube.com/watch?v=G7-zh7Sebr8
         | 
         | * Via: https://forums.liveatc.net/atcaviation-audio-
         | clips/ual-328-u...
        
           | bredren wrote:
           | How come the discrete audio on 120.15 was not available?
        
           | EE84M3i wrote:
           | If anyone else is wondering what ZIMMR means in this context,
           | it is a specific feature of the Denver airport: https://ja.fl
           | ightaware.com/resources/airport/DEN/DP/ZIMMR+TW...
        
             | repiret wrote:
             | A specific location. Waypoints used in IFR approaches are
             | given unique, 5-letter, usually pronounceable, names.
        
               | tialaramex wrote:
               | As well as being unique they're chosen to avoid similar
               | sounding ones being near each other. So KITES and SITES
               | might both exist but they'd never be anywhere that you
               | could confuse one for the other.
        
         | mannykannot wrote:
         | WRT the debris video: personally, I would be paying more
         | attention to looking for anything falling in my direction. The
         | debris may flutter like falling paper, but they are much more
         | substantial.
        
           | anonAndOn wrote:
           | Those are heavy objects falling onto a kids soccer field and
           | nobody yells "HEADS UP!", "FORE!" or "RUN FOR COVER!". How
           | considerate.
        
             | dralley wrote:
             | It looks like they've got plenty of time to move out of the
             | way.
        
               | jabl wrote:
               | I'd guess looking upwards at some awkward shaped objects
               | falling down, it's not easy to guess where they will come
               | down.
        
               | jacquesm wrote:
               | If this ever happens to you and it seems like the falling
               | object is not moving in your field of view: run away at a
               | 90 degree angle.
        
         | thiagocsf wrote:
         | The right engine was out and the pilot chose to do a left turn.
         | Is the choice related?
        
           | iawix wrote:
           | It's good airmanship to turn into your "good" engine.
        
             | jabl wrote:
             | Why? Surely it's easier to turn the other way? Then again,
             | it's not a dogfight, so maybe less chance of losing control
             | if turning into the working engine?
        
               | benhurmarcel wrote:
               | > Surely it's easier to turn the other way?
               | 
               | That's exactly why. Because then it helps you getting out
               | of your turn, instead of fighting against it.
        
               | jacquesm wrote:
               | Because you may not be able to get out of your turn that
               | way. The aircraft 'wants' to turn over the bad engine so
               | you could easily get caught in a feed-forward situation.
        
       | dzonga wrote:
       | less than 30 days ago. I made a comment[0] here on HN that Boeing
       | planes safety records make your bowels shift, if you look up
       | their safety records before you fly. glad everyone on that flight
       | was safe. but yeah airlines need to have a disclaimer when you
       | fly certain planes.
       | 
       | [0]: https://news.ycombinator.com/item?id=25904047
        
         | cranekam wrote:
         | In that comment you assert 777s "break in half". Where did you
         | get this from? There has been 8 hull losses and only one "broke
         | in half" (Asiana) after it was basically flown into the ground.
         | 
         | https://en.m.wikipedia.org/wiki/Boeing_777#777-200ER
         | 
         | Your comment, which implies the 777 is unsafe, is nonsense. The
         | 777 has a great record.
        
       | throwawayboise wrote:
       | Other discussion, ostensibly by professional pilots
       | 
       | https://www.pprune.org/rumours-news/638797-united-b777-uncon...
        
       | emmanueloga_ wrote:
       | "the right hand engine's (PW4077) inlet separated associated with
       | the failure of the engine."
       | 
       | This description is rather nonchalant but how can this possibly
       | happen!? May this be related to the age of the aircraft?
       | 
       | "Ground observers reported hearing the sound of an explosion like
       | bang, smoke and saw the debris falling down."
       | 
       | I mean, an engine about to explode sounds like the kind of thing
       | that a routine pre-flight inspection should be able to catch...
        
         | ceejayoz wrote:
         | Failures happen. So do mistakes. We design planes to be
         | resistant as a result.
         | 
         | There are many engine issues that would not be visually
         | apparent. Metal fatigue in the turbine blades, a bolt that's
         | the wrong size for its hole. Aviation has seen it all.
        
         | terramex wrote:
         | It looks like of of the fan blades detached and ripped cowling
         | off. Such engine defects are usually not detectable during
         | routine pre-flight inspection, for that you need to disassemble
         | whole engine, check bearings, do x-ray inspection of turbine to
         | look for metal fatigue or micro cracks etc.
         | 
         | Two years ago there was very similar incident, also Boeing 777
         | with PW4000 engine: http://aerossurance.com/safety-
         | management/ndi-failures-b777-...
        
         | markdown wrote:
         | Lots of passenger planes have been flightless for months as a
         | result of travel restrictions.
         | 
         | It would be interesting to see how long this particular bird
         | has been sitting on the ground.
        
           | easton wrote:
           | It has not been grounded. The last flight was earlier this
           | morning from Chicago (ORD) to Denver.
           | 
           | https://flightaware.com/live/flight/N772UA
        
           | pwc wrote:
           | It is an interesting question. According to AVHerald the tail
           | number for this plane is N772UA:
           | 
           | https://www.flightradar24.com/data/aircraft/n772ua
           | 
           | ... so it looks like it's been flying at least for the last
           | week.
        
       | funkaster wrote:
       | liveatc recording:
       | https://forums.liveatc.net/index.php?action=dlattach;topic=1...
        
       | terramex wrote:
       | Almost identical incident happened 3 years ago - the same type
       | (B777-200), the same engine (PW4077), the same operator (United
       | Airlines), the same side (right engine), the same failure
       | (unconfined engine failure).
       | 
       | https://avherald.com/h?article=4b4e8ca7&opt=0
       | 
       | I would not be surprised if the whole fleet of this type/engine
       | gets grounded for some time.
        
         | guidedlight wrote:
         | The failure was blamed on lack of training for inspectors.
        
         | acvny wrote:
         | Also, the same destination: Honolulu. And only 1 digit
         | difference in registration number (N773UA in 2018 vs N772UA in
         | 2021).
        
           | acvny wrote:
           | Must be a bad batch. Please return by post with batch number
           | visible for a refund and let us know what you didn't like
           | about the product
        
         | pdonis wrote:
         | From the report on the previous incident (Feb 2018), it looks
         | like NTSB determined that the root cause was a cracked fan
         | blade in the engine that should have been spotted on a previous
         | inspection but wasn't. That doesn't just implicate this
         | type/engine; it implicates the inspection procedures in
         | general.
        
         | thgaway17 wrote:
         | It was a bird strike.
        
         | leesalminen wrote:
         | And I'm supposed to fly on a 777-200 to Denver operated by
         | United in just a few days. Yay!
        
           | reddotX wrote:
           | good luck!
        
           | valuearb wrote:
           | The 777 has been flying for 25 years with almost no fatal
           | accidents. Unless your flight will be flying over Russian
           | anti-aircraft missile batteries or through a wormhole above
           | Malaysia, you should be perfectly safe.
        
             | codingdave wrote:
             | Another way of looking at it is that after flying and
             | accumulating 25 years of wear and tear without major
             | incident, we now have seen a repeatable flaw that these
             | aircraft may encounter due to their age.
        
               | hazeii wrote:
               | Engines are separate from the airframe; on big commercial
               | aircraft the engines get swapped/moved around all the
               | time (the engines may well be on lease, separate to the
               | lease on the airframe). Thus, in this sort of situation
               | it's the engine's history that'll be important, rather
               | than the airframes.
        
               | danaliv wrote:
               | Until the NTSB investigates, there's no way to know
               | whether age has anything to do with it. It might. It
               | might not. There could be a common cause, or there isn't.
               | 
               | We don't know yet.
        
               | ekianjo wrote:
               | > these aircraft may encounter due to their age
               | 
               | Unlike some codebases, aircrafts actually have mandated
               | maintenance. Which is why most accidents are due to human
               | error and not massive technical failures.
        
               | eru wrote:
               | And often pretty silly and stupid human errors.
               | 
               | (That's a feature, not a bug! The pervasive checklists
               | and general professionalism mean that most 'normal' human
               | errors are recovered from without enough consequences to
               | make it into the news.
               | 
               | So only the really unlucky and incompetent are what we
               | usually hear about.)
        
               | ajarmst wrote:
               | As well as two demonstrations that the aircraft meets the
               | design specification that even a catastrophic failure in
               | the worst stage of flight is easily recoverable. I'd
               | expect an increased inspection rate, possibly some new
               | mandated ND testing for fractures and discontinuities
               | (the last one was an LP shaft failure, IIRC).
               | 
               | One thing that does bug me, though is that we now have
               | two events where the shroud was lost. Were these
               | _uncontained_ failures (problematic because of potential
               | for wing damage) or contained faiLures followed by
               | aerodynamic shedding of the damaged shroud (system
               | functioning as designed). I 'm also somewhat concerned
               | about the fire remaining in the burner stage. Might have
               | just been lubricants, but I'd want to make sure the fire
               | handle had been pulled and investigate whether it worked
               | correctly.
        
               | dognotdog wrote:
               | It looks it's the "cowling" that was lost, not the
               | protective shroud / containment around the fan (and the
               | rest of the engine) that keeps the fan/compressor/turbine
               | blades from becoming high speed radial projectiles when
               | they break off at full speed.
        
               | ajarmst wrote:
               | Agreed. The last one was pretty clearly a failure of a
               | shaft or turbine, and the damage was much more obvious.
               | This might be something completely different.
        
               | interestica wrote:
               | > As well as two demonstrations that the aircraft meets
               | the design specification that even a catastrophic failure
               | in the worst stage of flight is easily recoverable.
               | 
               | But in that type of failure, you can't control where the
               | pieces go.
               | 
               | https://abc7ny.com/philadelphia-emergency-landing-
               | southwest-...
               | 
               | It resulted in depressurization and partial
               | ejection/death.
        
               | kortilla wrote:
               | That's a different type of failure. Uncontained vs
               | contained.
        
               | interestica wrote:
               | Kinda. While the 2018 incident was "contained", it still
               | resulted in damage to the fuselage.
               | 
               | "Two small punctures were found in the right side
               | fuselage just below the window belt with material
               | transfer consistent with impact from pieces of an engine
               | fan blade"
               | 
               | (From the link in parent to this thread
               | https://avherald.com/h?article=4b4e8ca7&opt=0)
        
               | ajarmst wrote:
               | Not 'kinda'. Debris exiting the engine housing with
               | sufficient energy and in a direction that leads to damage
               | of other systems is the literal definition of an
               | unconfined engine failure (i.e. it can spit as many parts
               | as it wants to out the exhaust). There is a band of
               | armour around the plane of the fans that should prevent
               | any blades leaving the engine perpendicularly. If there
               | was fuselage or wing damage from debris, that was an
               | unconfined failure and would require investigation as a
               | major fault.
               | 
               | However, loss of the shroud doesn't necessarily imply
               | there was a confinement failure. Damage to the shroud
               | during the event can easily lead to the cowling shedding
               | aerodynamically, which is also part of the design: the
               | last thing you need is more drag on the dead engine side.
               | We can't tell which that was in this case, but it's
               | important that we do---the design criteria specifying
               | that the aircraft can be safely recovered from a
               | catastrophic single engine failure during any stage of
               | flight would assume the failure is confined to the
               | engine.
        
               | ashtonkem wrote:
               | Engine age isn't the same as airframe age, and components
               | don't age linearly with calendar time; they age with
               | flight hours or pressurization cycles. Without access to
               | a log book, it's impossible to know how old an engine is
               | or when it was last overhauled.
        
               | bluGill wrote:
               | That isn't completely true. We don't know exactly, but
               | the documented time between overhaul and the life of the
               | airframe place upper bounds on those.
               | 
               | Some cheap airlines might ignore those rules, but none in
               | the US. (Only the poorest, most corrup, countires in the
               | world will ignore those limits)
        
               | ralph84 wrote:
               | Indeed, for a 25-year-old airframe with the utilization
               | it would have at a major carrier like United there's
               | basically no way the engines hanging on it now could be
               | the same engines it was delivered with.
        
               | throwawayboise wrote:
               | Aircraft undergo regular preventative maintenance checks,
               | with letter codes A - D. The D check being the most
               | comprehensive, it occurs every 6-10 years and basically
               | the entire aircraft is taken apart and inspected, looking
               | for among other things anything like stress fractures,
               | corrosion, unusual wear, etc.
               | 
               | https://en.wikipedia.org/wiki/Aircraft_maintenance_checks
               | #D_...
               | 
               | A commercial aircraft does not just accumulate wear and
               | tear for 25 years until something breaks. They can
               | basically fly indefinitely, but in reality after two or
               | three D checks they are usually retired because the cost
               | of the D check is more than the value of the aircraft.
        
               | touisteur wrote:
               | Beware of the dangers of preventative maintenance, where
               | sometimes while replacing or inspecting or re-mounting
               | inspected parts, the maintenance crew breaks something
               | that was OK and probably going to be working fine for
               | years.
               | 
               | But yeah, a D check is so expensive I've heard there's a
               | habit of dumping the aircraft on less observing flying
               | companies some thousand miles before it comes up...
        
               | Leherenn wrote:
               | A minor point, it's not based on miles, but cycles
               | (takeoffs/landings) for structural parts or hours for
               | engines.
        
               | touisteur wrote:
               | You're right, thanks for the correction.
        
               | pdonis wrote:
               | _> Aircraft undergo regular preventative maintenance
               | checks_
               | 
               | And in a similar incident in February 2018 on a 777
               | (referred to upthread), one of those checks was found to
               | have failed: the NTSB determined that the root cause was
               | a cracked engine fan blade that should have been detected
               | on a previous inspection (and that would have resulted in
               | the blade being replaced), but wasn't. If this incident
               | turns out to have a similar root cause, that means there
               | are issues with the preventive inspection and maintenance
               | process.
        
               | dzhiurgis wrote:
               | > basically the entire aircraft is taken apart
               | 
               | How is that safe unless you've got a production line
               | doing it? Seems impossible to re-assemble it in the same
               | way as it was done in factory...
        
               | donarb wrote:
               | It's not taken totally apart, but it is stripped of the
               | interior down to the bare metal, all wiring is
               | checked/replaced as needed. All mechanical parts like the
               | flaps and landing gear are removed and checked for wear.
               | The skin is checked for cracks. This is done every 5
               | years for planes, taking about 5-6 weeks to complete.
               | 
               | Here's https://www.youtube.com/watch?v=WLil1MZmchI
        
               | ghotli wrote:
               | Great context. I gained a lot of respect for aviation's
               | use of checklists and procedures from the book 'The
               | Checklist Manifesto'
               | 
               | In this case, something obviously went awry and it's both
               | engineering, planning, and a miracle no one died or was
               | crushed from debris from above. Regardless, comments like
               | yours leave me feeling far more confident in this sort of
               | thing.
        
               | eru wrote:
               | > In this case, something obviously went awry and it's
               | both engineering, planning, and a miracle no one died or
               | was crushed from debris from above. [...]
               | 
               | Yes, though even something going wrong doesn't
               | necessarily mean that we'd need to change any procedures.
               | 
               | Sensible procedures bring risks down to acceptable levels
               | at an acceptable price. That level of risk is generally
               | still more than 0%.
        
               | sandworm101 wrote:
               | >> a repeatable flaw that these aircraft may encounter
               | due to their age.
               | 
               | There are hundreds of flaws. Aircraft are not perfect.
               | Any large airframe sees lots of little things break every
               | year. That's what inspections and maintenance are for.
               | But the system is designed so that such things never add
               | up into something really bad. Be worried about the
               | aircraft without flaws. To me, that means it either never
               | gets used or isn't being inspected properly.
        
             | StopHammoTime wrote:
             | Or also if your pilots have just finished their type rating
             | and used to fly A320s. Hopefully they remember that you
             | actually need to manage your throttle on a Boeing!
        
               | jey wrote:
               | Which incident are you referencing here?
        
               | nirguzam wrote:
               | Are you suggesting that there's a germane difference
               | between the fly-by-wire FADECs on these two aircraft
               | types?
        
           | alamortsubite wrote:
           | If you're riding in an automobile to/from the airport, you
           | have reasonable cause for concern.
        
           | leetrout wrote:
           | And you have nothing to worry about. Statistically you really
           | have nothing to worry about given this incident happening
           | today.
           | 
           | Enjoy your flight and enjoy Denver. Get a donut from Voodoo
           | for me.
        
           | Aperocky wrote:
           | Well, wouldn't be surprised if the aircraft is literally this
           | one, and you'll now fly on a different one.
        
           | jfk13 wrote:
           | At least it's unlikely to be _that_ 777-200.
        
             | viraptor wrote:
             | That specific plane will go through a lot of rebuilding,
             | checks, thorough investigation, etc. Given a choice, I'd
             | take that plane over another one.
        
               | AdamJacobMuller wrote:
               | Yeah but not if they rush the rebuilding and complete it
               | in a few days. I suspect that's gonna require too much
               | duct tape and bubble gum.
        
               | Reason077 wrote:
               | Assuming there's no damage to the airframe itself, it
               | could be back in the air pretty quickly. Changing the
               | engine is a fairly routine procedure, which takes about a
               | day:
               | 
               | https://blog.virginatlantic.com/change-aircraft-engine/
        
           | oh_sigh wrote:
           | Look on the bright side - you're probably more likely to die
           | from catching COVID-19 from another person on the flight.
        
             | tekromancr wrote:
             | Not sure which is the worse way to go. 3-8 mins of flaming,
             | falling terror; or weeks of facing potential death in a
             | hospital
        
         | djmips wrote:
         | 2020: (JAL 777 same engine)
         | https://www.youtube.com/watch?v=O-_IAKCBTxc&t=10s
         | 
         | 2018: United 777 same PW engine (seems very similar but without
         | fire) https://www.youtube.com/watch?v=O-_IAKCBTxc&t=10s
         | 
         | 2016: KAL 777 same PW engines (aborted takeoff after engine
         | failure) https://www.youtube.com/watch?v=9bHrW_34kAk
         | 
         | All planes had zero casualties.
        
           | Kye wrote:
           | If I were an airline's insurer, I wouldn't want to gamble on
           | the good luck lasting.
        
             | sandworm101 wrote:
             | Not luck. Design. These failures are anticipated. That they
             | can be handled so well is testimony to the energy and
             | regulation put into engine safety over decades. Whereas
             | once such failures could down an airline, killing all on
             | board, they can now be handled safely.
        
               | pdonis wrote:
               | _> These failures are anticipated_
               | 
               | Sort of. The possibility of some types of failure is
               | anticipated in the design of other parts of the engine.
               | But there are also inspection procedures in place to
               | ensure that engine parts that might fail are replaced
               | before they fail. A report on a previous incident in Feb
               | 2018 (referred to upthread) says that the root cause was
               | a cracked engine fan blade that should have been detected
               | on a previous inspection but wasn't. Failures that are
               | supposed to be prevented by inspection and replacement of
               | parts are not necessarily also allowed for in other parts
               | of the design. So it's quite possible that luck is
               | involved here as well and that a future failure of this
               | type could have much worse consequences.
        
               | sandworm101 wrote:
               | fan blade failures are expected. Engines are designed to
               | contain failed blades. There is a huge test that is done
               | whereby a blade is "failed" at full throttle. Engine dies
               | but damage is to be contained.
               | 
               | https://youtu.be/j973645y5AA
               | 
               | (A380 "blade off" test, rare footage of giant engine
               | failing)
        
               | BrianOnHN wrote:
               | How do you safely handle the debris falling to the
               | ground?
        
               | sandworm101 wrote:
               | You dont. A few pounds of engine parts is infinitely
               | better than the previous option, many tons of airliner
               | falling on a house.
        
               | wavefunction wrote:
               | @sandworm How about a third option where neither the
               | plane nor the debris falls?
        
               | sandworm101 wrote:
               | The risk of falling debris actually killing someone pales
               | in comparison to the risks of it perhaps doing more
               | damage onboard the aircraft. A loose part near/inside an
               | engine is no longer doing its job and could cause more
               | damage where it is. And the ground is a big place. Drop a
               | random pin in google maps. Then zoom in to see if it is
               | actually on someone's head. This is lottery odds
               | territory.
               | 
               | Objects drop from aircraft all the time, daily. It isn't
               | generally newsworthy unless part of a larger story. And
               | even then, only if the object is found and recognized as
               | being from an aircraft. Small rocks also fall daily from
               | space, probably more by weight than aircraft-related
               | objects, yet virtually nobody ever gets hit by space
               | rocks.
        
               | ClumsyPilot wrote:
               | To add to that, 100 tons of spacerocks hit eath every
               | day. I dont think 100 tons of parts fall of airliners
               | daily.
               | 
               | That being said, there was a russian spacecraft that
               | disintegrated and hit someone house, in the middle of
               | siberia bo less. So it does happen, but its freak ecen3ts
               | territory.
        
               | airhead969 wrote:
               | False equivalency. 100 T of diffuse material reaching
               | Earth, likely burning up, isn't the same as or even
               | remotely comparable to parts falling off aircraft due to
               | man-made negligence. Jettisoning honeycomb cowling
               | sections because a particular model of engine is
               | relatively unreliable, through design, manufacturing, or
               | maintenance, isn't an excuse for not fixing it or not
               | using a better engine if it cannot be fixed economically.
               | 
               | Could you proofread and type correctly so we understand
               | what you're saying? I can't read all of what you're
               | saying.
        
               | sandworm101 wrote:
               | Oh, if you are going to include manmade space-related
               | objects there have been many deaths. Dig into how many
               | Chinese rocket stages have landed on villages. If we
               | include such things as "aviation" I would retract my
               | above statements re debris. Rockets do sometimes fall on
               | people.
               | 
               | https://en.wikipedia.org/wiki/Intelsat_708
               | 
               | https://arstechnica.com/science/2019/11/china-keeps-
               | dropping...
               | 
               | "It has happened many times before, including most
               | infamously in 1996 when a Long March 3B rocket veered off
               | course shortly after a launch and crashed into a village.
               | Chinese officials reported six dead from the accident,
               | although Western sources have speculated that hundreds of
               | Chinese citizens may have died in the accident."
        
               | o-__-o wrote:
               | Why compare two sovereign nations with vastly different
               | safety regulations?
        
               | sandworm101 wrote:
               | I didnt. I only said that rockets sometime crash on
               | people and gave an example. Nobody is comparing countries
               | in this thread. Aviation is about as international as any
               | industry can be.
        
               | galangalalgol wrote:
               | I'm sure people PW is working on that, but the failure
               | rates on commercial aircraft parts are already
               | ridiculously low. Bad things will always happen.
        
               | airhead969 wrote:
               | "Bad things will always happen" is a despicable shrug
               | mentality. Bad things happen when people don't have their
               | acts together in design, engineering, manufacturing,
               | maintenance, and operation. The failure rates should be
               | striving for zero, unlike the stunts Boeing has pulled on
               | 737NG, MAX, and the 787.
        
               | galangalalgol wrote:
               | Totally agree with you on the recent laxness in design
               | and the regulatory capture that allowed it. But treating
               | zero as a feasible goal is unrealistic. I've done code
               | inspections for safety of flight code and making sure you
               | have 100% coverage and branch coverage not just in the
               | high level code but in assembler still doesn't get
               | everything. You try to make sure that redundancy saves
               | you (seriously boeing!) But common mode errors and just
               | human fallibility to see all the possibilities mean we
               | miss stuff. And all this is so much easier in software
               | than in mechanical designs where redundancy sometimes
               | just isn't doable. We shouldn't give up best practices,
               | but we shouldn't have unreasonable expectations of them
               | either. And not every engineering failure implies a
               | failure in engineering process.
        
               | airhead969 wrote:
               | I never said it was feasible, you did. It must be strived
               | for, because that's the difference between excellence and
               | crap.
        
               | galangalalgol wrote:
               | I wanted to clarify my last statement. Even when best
               | practices are followed bad stuff happens, and that
               | doesn't necessarily mean best practices need to change.
        
               | airhead969 wrote:
               | Of course not. Make improvements rather than knowingly
               | shove-in bad Ducommun parts on the line or crappy MCAS.
               | Also, hold manufacturers responsible when they take cost-
               | shortcuts, sacrifice safety, and kill people. Boeing
               | routinely gets a slap for doing so since it's also
               | considered a strategic defense contractor, part of the
               | MIC that greases palms in DC.
        
           | frogpelt wrote:
           | You posted the same link twice.
        
             | tim333 wrote:
             | I guess the 2020 JAL one could be
             | https://www.youtube.com/watch?v=k2ZJjYQj2bY
             | 
             | There's some good video off the current one on the BBC site
             | https://www.bbc.com/news/world-us-canada-56141673
        
         | hazeii wrote:
         | I thought it was 'confined' if the containment ring did its
         | job? If it had failed (like not supposed to) it would have been
         | a whole lot worse.
        
           | colechristensen wrote:
           | The plane landed and didn't blast enormous holes with ejected
           | compressor blades. That's a successful failure.
        
             | underseacables wrote:
             | Is that what happenes when The fan blades fly off and hit
             | the airplane?
        
               | touisteur wrote:
               | Ugh look up QF-72 for an A380 Rolls-Royce engine
               | containment failure...
        
               | martyvis wrote:
               | QF-32. (BTW the pilot Richard Champion de Crespigny wrote
               | a fantastic book on the incident. The intensity of going
               | though procedures on an iPad and manuals as alarms were
               | going off, while remembering to just fly the plane, was
               | the thing that most sticks in my mind.
        
               | touisteur wrote:
               | Sorry, right, always mixing up those two. Best lessons
               | from the book for me are:
               | 
               | 1- meet the designers, understand the "why"s and not only
               | the descriptive posthoc documentation
               | 
               | 2- when you don't trust your instruments, keep following
               | the procedures, checklists, (for this you need an
               | excellent, trained, cold-headed team), and eventually try
               | to reconstruct 'what aircraft you have'
               | 
               | 3- trust the automated checklists but not too much!
               | Crosscheck what's asked of you, with what you know of the
               | aircraft. Since you know the 'why's you know the
               | automated checklist system's designers probably never
               | expected an aircraft with that much damage to keep
               | flying...
               | 
               | 4- there are no hall-passes for heroes. At the end De
               | Crespigny fails his evaluation (the flight was an
               | evaluation flight, with an instructor on board).
               | 
               | All around a great, great book for systems people.
        
               | mcdevilkiller wrote:
               | Are you sure? That was an A330, and a failure on one
               | ADIRU.
        
               | touisteur wrote:
               | Aaaaaah always mixing this and QF-32 :-( sorry. The book
               | by Richard de Crespigny is a must read if you can find
               | it. Great.
        
               | colechristensen wrote:
               | Pieces on the inside of jet engines are spinning between
               | 2,000 and 12,000 rpm. They should all be properly
               | contained in an airliner, but before that was the case of
               | one fan blade broke and hit the plane it could look like
               | a bomb blew an enormous hole in the side of the plane.
               | These small pieces have a huge kinetic energy because
               | they're spinning so fast.
               | 
               | Nothing bad happening, everyone uninjured and a plane
               | making an orderly airport emergency landing is many
               | layers of safety systems all working properly.
        
               | kyshoc wrote:
               | That's almost exactly what happened on Southwest 1380[0]
               | a few years ago.
               | 
               | [0]: https://en.wikipedia.org/wiki/Southwest_Airlines_Fli
               | ght_1380
        
               | benhurmarcel wrote:
               | To add to the topic, aircraft structure and systems are
               | made to withstand the projection of those debris hitting
               | with "infitite" energy. That means for every trajectory
               | possible, it's considered that a part flies through
               | everything in its path. The aircraft still has to land.
        
               | o-__-o wrote:
               | The wing is an exceptionally strong component of the
               | aircraft. It's usually the freak accidents where you hear
               | of a fuel tank being ruptured or control or hydraulic
               | lines being cut. In all of these accidents I bet there is
               | wing damage but the plane is able to continue as usual
               | 
               | WW2 fighter planes anyone?
        
               | lm28469 wrote:
               | Most of the "skin" of a plane is only a few mm thick [0]
               | it doesn't take much to puncture, I mean, it does, but
               | thin turbine blades made to resist birds impact at 10k
               | rpm would cut through it like butter.
               | 
               | [0]
               | https://aviation.stackexchange.com/questions/45566/how-
               | thick...
        
               | hazeii wrote:
               | As ever, more detail and clear explanations on pprune[0].
               | 
               | As one commenter put it, to an ER doctor this is a
               | shallow wound with lots of blood.
               | 
               | [0] https://www.pprune.org/rumours-
               | news/638797-united-b777-uncon...
        
             | hazeii wrote:
             | Plenty of youtube videos of a blade-off test - here's a
             | short one [0] of an A380 Rolls Royce engine testing. That's
             | about PS9,000,000 of engine being destroyed in this
             | (successful) test.
             | 
             | [0] https://www.youtube.com/watch?v=5-8_Gnbp2JA
        
               | dtgriscom wrote:
               | At the beginning of the video the blades seem to be
               | spinning at about 2RPS, but after the explosion they're
               | spinning much faster. I presume the former was an
               | artifact of the camera's frame rate.
        
               | hazeii wrote:
               | They normally have high-speed cameras running; that short
               | video is a mish-mash of super-slow-mo and regular speed
               | footage. There are much longer versions on YT, e.g. this
               | one [0] which covers it in more detail (watch the people
               | in the room jump when it blows - despite being a fair
               | distance away).
               | 
               | [0] https://www.youtube.com/watch?v=j973645y5AA
        
           | implements wrote:
           | That's my understanding - "confined" meaning nothing flying
           | tangentially away from the engine and hitting the fuselage or
           | wing.
           | 
           | Saying that, resultant vibration causing the inlet and
           | nacelle cowling to separate isn't supposed to happen either -
           | because of the serious risk to the tail.
        
         | throw0101a wrote:
         | Animated recreation with ATC audio of that flight (UA1175):
         | 
         | * https://www.youtube.com/watch?v=O-_IAKCBTxc
         | 
         | Animated recreation with audio of this one (UA328):
         | 
         | * https://www.youtube.com/watch?v=G7-zh7Sebr8
         | 
         | * Via: https://forums.liveatc.net/atcaviation-audio-
         | clips/ual-328-u...
        
         | nradov wrote:
         | Korean Air had an incident in 2016 where a PW4000 on a Boeing
         | 777 disintegrated during takeoff.
         | 
         | https://en.wikipedia.org/wiki/Korean_Air_Flight_2708?wprov=s...
        
       | IndySun wrote:
       | So, large, popular, commercial airplanes, are passing their
       | mandatory and thorough pre-flight safe-to-fly inspections, but
       | then having catastrophic failures within minutes of take off.
       | 
       | It must mean that pre-flight inspections (to quote George Carlin)
       | an illusion of safety? ie Not fit for purpose.
        
       | soheil wrote:
       | I like how people are just standing next to pieces of plane and
       | playing soccer in the background, going like just another day
       | with pieces of plane falling out of sky [0]
       | 
       | [0]
       | https://avherald.com/img/united_b772_n772ua_denver_210220_3....
        
         | Aperocky wrote:
         | Well once they've already fallen there's not much more to it..
         | It's not like it's a continuous stream of debris coming from
         | somewhere. But it does look dangerous when it would have first
         | fell though.
        
         | jacquesm wrote:
         | Better than that they move the pieces. Finding the pieces in
         | their exact location + weather pattern can give important clues
         | as to the reason why this happened in the first place.
        
       | rossjudson wrote:
       | You should see the accident from the day before:
       | https://avherald.com/h?article=4e35302b&opt=0
       | 
       | The plane began to "distribute engine parts". The pictures show
       | us just how impressive the distribution was.
        
         | ledauphin wrote:
         | same day, actually - this was only about 8 hours ago.
        
       | sydney6 wrote:
       | Oddly enough, something similar happened today just a few
       | kilometers from where i live.
       | 
       | https://www.aviation24.be/airlines/longtail-aviation/boeing-...
        
         | ledauphin wrote:
         | today was quite weird for Boeing airplanes, as well as for
         | United. United Flight 1832 (a 737-8) from Cancun to Houston had
         | a single engine shutdown on the way and had to divert to New
         | Orleans.
        
           | TangoFox wrote:
           | I'm an Air Traffic Controller at Houston Center, and a
           | regular user of this website. Today I was the Radar Associate
           | controller in the Ocean West sector when that aircraft flew
           | through.
           | 
           | The Radar Associate works alongside the Radar Controller, and
           | performs coordinations and other actions to assist the Radar
           | Controller. It is the Radar Controller who talks with the
           | aircraft on frequency.
           | 
           | In the Ocean West sector, the Radar Associate controller
           | coordinates with Mexico's Air Traffic Controllers to
           | determine safe routes, altitudes, and crossing times at the
           | FIR boundary, as well as pass along any other pertinent
           | information.
           | 
           | I won't answer any questions about today's event here, but if
           | anyone has any other questions, feel free to ask. I will also
           | double-check the FAA's social media guidelines when I go back
           | to work tomorrow. So, if I don't answer your question today,
           | please check tomorrow.
           | 
           | TF or "Tango Foxtrot" are my operating initials - something
           | which every Air Traffic Controller has and is unique per
           | facility. We use our operating initials to identify ourselves
           | when we perform coordinations via the landline.
           | 
           | I was also a Radar Associate controller at HCF Center (in
           | Hawaii) for United Flight 1175, a Boeing 777, from San
           | Fransisco to Honolulu when it lost its engine cowling back in
           | 2018.
           | 
           | The views expressed here are my own and not necessarily those
           | of FAA.
        
             | ledauphin wrote:
             | Actually, one thing I was wondering after I got the alert
             | about the 7700 (via flightradar24) - is there anything I'm
             | missing in terms of a reasonably reliable way to figure out
             | what Center frequency a given airplane is currently
             | communicating on, when not low enough to be talking to
             | Approach? I'm assuming there isn't, because handoffs from
             | departure seem to vary frequencies when I fly.
        
               | TangoFox wrote:
               | You would need charts that show the different sector
               | boundaries and their altitude or flight level stratums.
               | Sectors can be combined, so you might be given a
               | different frequency in the same area at different times
               | of the day and/or days of the week.
               | 
               | With Approach, sector boundaries can also change
               | depending on which runway(s) they're landing.
               | 
               | You could potentially call up the facility and ask for
               | copies of the sector charts, but I don't know what kind
               | of response you will get.
               | 
               | Right now due to COVID-19, facility tours are not
               | allowed, otherwise you could see ATC in-person and ask to
               | take a look at their charts then, as well as ask the
               | Controllers any questions, workload-permitting.
               | 
               | The facilities that I've worked at (HCF Center and
               | Houston Center) have been happy to give tours, but they
               | have to be during normal business hours, and you have to
               | be a United States citizen. For a tour, I suggest
               | organizing a group of pilots or others interested in
               | aviation, rather than just going by yourself.
               | 
               | The views expressed here are my own and not necessarily
               | those of the FAA.
        
             | Hnrobert42 wrote:
             | Is RADAR Controller the senior position and RADAR Associate
             | the junior position? That is, does one normally progress
             | from Associate to Controller? How long does it take to
             | progress from one to the next? Is it common/expected for
             | people in your position to move to different airports?
        
               | [deleted]
        
               | TangoFox wrote:
               | Radar Controllers and Radar Associates are just staffing
               | positions.
               | 
               | Some background information to build on...
               | 
               | An Air Traffic Controller's job title when they start out
               | is Air Traffic Control Specialist. An Air Traffic Control
               | Specialist starts out in the AG pay band (Academy
               | Graduate). When that Controller gets certifications, they
               | move up to the D1 pay band (Developmental), then to D2,
               | D3, and when they get all of their certifications or
               | "fully certify", they end in the CPC pay band and their
               | job title changes to Certified Professional Controller.
               | 
               | The Radar Controller position is also called the R-side,
               | and the Radar Associate position is also called the
               | D-side. A trainee needs to certify on all of their
               | D-sides before they start training on their R-sides.
               | 
               | So basically the answer to your first two questions is
               | "yes". However there can be a more experienced controller
               | working the D-side while a new controller is working the
               | R-side. The Air Traffic Controllers rotate through the
               | different positions throughout the day. It is based on
               | when someone arrives for their shift, or comes back to
               | the control room from their break, they check with the
               | controller that has been on a position the longest, and
               | asks that person if they want a break. If not, the
               | Controller moves on to the next person who has been
               | working the longest, and so forth.
               | 
               | ARTCCs or Air Route Traffic Control Centers or just
               | "Centers", are divided into "specialties" (or "areas")
               | that controllers are assigned to. Each specialty is
               | divided into sectors. At the minimum, each sector needs
               | to staffed by a Radar Controller. If the sector is busy
               | with a lot of traffic or is complex due to weather
               | events, or maybe traffic being rerouted from another
               | sector, then a Radar Associate position will be staffed
               | at that sector. If traffic is very light, for example in
               | the middle of the night, sectors can be combined and one
               | Radar Controller will work multiple sectors and talk to
               | multiple aircraft on different frequencies.
               | 
               | The time it takes to get certified depends on many
               | factors. It could be anywhere from one month, to six
               | months. From starting out to get fully certified, can
               | take anywhere between two years, to five years. It
               | depends on many factors, such as personal ability,
               | training opportunities, training backlogs, etc.
               | 
               | It is common for people to switch facilities at least
               | once. Some stay at their first facility, some move
               | several times. When a Controller graduates from the FAA's
               | training facility (that's where "Academy Graduate" comes
               | from), they are given a short list of facilities to chose
               | from. The list constantly changes based on the FAA's
               | staffing needs.
               | 
               | The FAA does do "direct hires" for people with previous
               | ATC experience (usually through military) directly into
               | certain facilities, but a new hire without experience
               | won't know where they'll go when they start out.
               | 
               | The views expressed here are my own and not necessarily
               | those of FAA.
        
               | kortilla wrote:
               | What expertise is it that ATC folks build up in all of
               | those years of training? Is it knowledge of plane
               | behavior by model, familiarity with the region, radar
               | behavior? Or is the majority of it the less tangible
               | "getting a feel for the flow of traffic to instinctively
               | pick out unusual behavior"?
        
               | TangoFox wrote:
               | (Edit to my parent comment: " It could be anywhere from
               | one month, to six months" to certify on a single sector,
               | but it's really more like one to three months.)
               | 
               | ---
               | 
               | All of the above.
               | 
               | Whenever an Air Traffic Controller transfers to a new
               | facility, or even transfers to a new specialty within a
               | facility, they have to train and get certified on all of
               | the new sectors. Each sector is different due to traffic
               | flow, types of traffic, equipment limitations, etc.
               | 
               | For the Houston Center Ocean specialty, equipment
               | familiarization is very important for Controllers. There
               | are 5 sectors: Ocean West, Ocean East, Offshore West,
               | Offshore Central, and Offshore East. Ocean West and East
               | deal primarily with aircraft flying between the United
               | States and Mexico. There are different airways that
               | aircraft can take, and each one has different
               | characteristics (crossing airways, airways defined by
               | RNAV fixes vs bearings off of VORTACs, radio coverage,
               | and radar coverage).
               | 
               | In the Offshore sectors, radio coverage is harder to
               | manage. There are multiple transmitters and receivers
               | that are located on different offshore platforms, and the
               | ocean elements and weather can affect the equipment. At
               | our positions next to the radar scopes, there are
               | touchscreens with many different buttons to select which
               | frequencies we want to monitor, transmit on, use primary
               | or backup sites, etc. Most sectors do not have to toggle
               | between different transmitters, but in the Offshore
               | sectors, that's a common occurrence. There are also
               | different transmitter sites for the Ocean sectors, so we
               | commonly get pilots saying that they're losing us on the
               | radio when we are talking to another aircraft a hundred
               | miles away, and we can hear the pilot just fine.
               | 
               | In the Ocean sectors, radar doesn't cover the middle of
               | the Gulf of Mexico, so we have to rely on aircraft
               | position reports unless they have ADS-B.
               | 
               | At HCF Center, there are mountains which block radar
               | coverage, so it's good to know where we can expect to
               | lose or establish radar contact with aircraft.
               | 
               | Yes, there is an element of becoming familiar with the
               | routine traffic. You see many of the same flights every
               | day, so you know where they are going. It got to the
               | point at HCF Center, where if someone told me a flight
               | number, I could tell them the departure and destination
               | airports without looking.
               | 
               | However, just like pilots, Air Traffic Controllers cannot
               | let routine turn into complacency. We can never just
               | assume anything, if we are unsure, we have to ask or
               | restate something. Safety is our number one priority.
               | 
               | The views expressed here are my own and not necessarily
               | those of the FAA.
        
               | [deleted]
        
               | [deleted]
        
       | wmij wrote:
       | Oddly a similar engine incident happened on the same United
       | flight route back in 2016. Apparently it was a bird strike back
       | then. Link: http://avherald.com/h?article=4999bec5
        
       | whatever1 wrote:
       | Maybe a system for emergency detaching of the failed engine with
       | a parachute would help aleviate the consequences of flying with a
       | uncontrollably vibrating fireball?
        
         | hugh-avherald wrote:
         | The system you propose already exists: fuse pins hold the
         | nacelle to the wing, and ensure the engine separates cleanly
         | from the aircraft if vibrations exceed dangerous levels.
        
         | doctor_eval wrote:
         | The kind of incident that happened on this flight is incredibly
         | rare, and in fact nobody got hurt. Sadly, while I get where
         | you're going, what you propose would almost certainly make
         | emergencies more common, not less.
         | 
         | To implement your solution you'd need at least:
         | 
         | - Some kind of mechanical release to let the engine go
         | 
         | - reliable ways to disconnect the electricity, fuel, control,
         | hydraulic and other connections without affecting the rest of
         | the aircraft when the engine detached
         | 
         | - a parachute with a release mechanism
         | 
         | Each of these mechanisms comes with its own disastrous failure
         | case:
         | 
         | - engine mechanically releases when it shouldn't, taking
         | everything with it (this has happened [0]), or engine is
         | released while still producing thrust despite the fire,
         | destroying the wing or tail
         | 
         | - hydraulic or other lines don't release when they should,
         | taking everything with it in an otherwise survivable situation
         | 
         | - parachute fails, dropping engine on people, parachute catches
         | fire in flight, parachute accidentally deploys in flight...
         | 
         | This is just off the top of my head, I'm sure there are many
         | other potential problems.
         | 
         | Sometimes the best solution is to work out what happened and
         | make it less likely to happen, rather than add stuff to catch
         | it after it fails.
         | 
         | [0] https://en.wikipedia.org/wiki/American_Airlines_Flight_191
        
         | _underfl0w_ wrote:
         | Oof. I would _not_ want to be the bystander whose house an
         | entire engine fell on, even with a parachute haha
        
           | argvargc wrote:
           | Reading this, my mind went straight to Donnie Darko
           | 
           | https://www.rottentomatoes.com/m/donnie_darko
        
         | mafuy wrote:
         | Surely such a system would add more causes of failure than it
         | could alleviate. I mean, you literally want to decrease the
         | bond between engine and wing.
        
       | dheera wrote:
       | Some honest questions here for experts:
       | 
       | 0. Why was the engine flaming in the first video? Why didn't the
       | pilots cut fuel to that engine immediately and use the other
       | engine to land?
       | 
       | 1. What is the best way to communicate issues to the pilot if
       | you're a passenger and see something the pilot can't see? For
       | example once I was sitting in the back of the aircraft on Airtran
       | and I saw a screw on the jet loosening and almost falling out. I
       | told a flight attendant but they were just kind of "Um hmm okay
       | thanks for letting us know! Would you like any orange juice?"
        
         | zoomablemind wrote:
         | > 1. What is the best way to communicate issues to the pilot if
         | you're a passenger and see something the pilot can't see?
         | 
         | Flight attendants is the passengers' interface to the whole
         | flight environment. BTW there's seniority rank among the
         | attendants too, chain of command, so to speak.
         | 
         | I would think that your observation was likely being noted, not
         | sure if relayed to the pilots. Juice is the best option, noone
         | needs to have a panic in the cabin.
         | 
         | Did you try to mention that observation again but at the
         | arrival, during the "Thank you, good bye!" time? Sometimes you
         | may even see the captain there.
         | 
         | P.S. Once, my flight was cancelled (all boarded already)
         | because the crew discovered a missing "Exit" sign in the cabin
         | and the mechanics at the airport could not find the exact part
         | for the plane model. Call this an attention to details!
        
           | portlander52232 wrote:
           | Once had a flight delayed for maybe an hour because an
           | overhead bin wouldn't close. Mechanic had to tape it shut
           | with special FAA duct tape, then sign the tape, then do an
           | impressive amount of paperwork right there and then.
        
         | interestica wrote:
         | https://en.m.wikipedia.org/wiki/Kegworth_air_disaster
         | 
         | - 8 January 1989
         | 
         | - The Kegworth air disaster - British Midland Flight 92, a
         | Boeing 737-400
         | 
         | - Pilots had an engine issue and shut down the _good_ engine by
         | mistake.
         | 
         | > The pilots throttled back the working right engine instead of
         | the malfunctioning left engine. They had no way of visually
         | checking the engines from the cockpit, and the cabin crew --
         | who did not hear the captain refer to the right hand engine in
         | his cabin address -- did not inform them that smoke and flames
         | had been seen from the left engine.
         | 
         | > Several passengers sitting near the rear of the plane noticed
         | smoke and sparks coming from the left engine.
         | 
         | > The pilots mistakenly shut down the functioning engine. They
         | selected full thrust from the malfunctioning one and this
         | increased its fuel supply, causing it to catch fire. Of the 126
         | people aboard, 47 died and 74 sustained serious injuries.
         | 
         | I have no idea what the best way to communicate would be, but
         | this is an example of an incident where it could have saved
         | lives. It would be good if there was a protocol. (Perhaps
         | requiring the captain's address to mention which engine they
         | believe has the issue).
        
         | mjg59 wrote:
         | Not an expert, but: if there had still been fuel supplied to
         | that engine, the fire would have been a lot worse. If you watch
         | the video the fire clearly becomes less intense over time, and
         | the footage of the landing suggests it's out by then. Remember
         | that fuel isn't the only flammable thing there - engines need
         | oil for lubrication, and in combination with whatever residual
         | fuel was in the system and potentially sprayed everywhere, it's
         | not surprising that you'd have enough to burn for a short time.
        
         | iawix wrote:
         | 0. Airliners have fire bottles filled with Halon to extinguish
         | flames, but they're ineffective if the cowling separates from
         | the engine. That's assuming this uncontained failure didn't
         | damage the bottle or wiring to it.
         | 
         | 1. Kudos, that's exactly the way to do it. If it was a screw on
         | top of the wing though, it was likely communicated later as one
         | screw coming off a panel isn't a big deal.
        
       | saagarjha wrote:
       | One of the best parts of everyone carrying a camera in their
       | pocket is you can get high-resolution images of incidents like
       | these as a matter of course.
        
         | gus_massa wrote:
         | Relevant xkcd https://xkcd.com/1235/
        
         | sumedh wrote:
         | and yet no good video of a UFO.
        
           | nexuist wrote:
           | Of course, you can explain your way out of that one too: The
           | aliens found out we got smartphones, so they decided to stop
           | making appearances now that they know they can be recorded.
        
       | anigbrowl wrote:
       | That second-last photo of the ?cowling? on the ground with no
       | damage to the house or the vehicle is just astonishing.
        
         | marwatk wrote:
         | I thought so too (I live a block away) but it actually did
         | significant damage:
         | 
         | https://v.redd.it/ishfm09j6pi61
        
       | m00dy wrote:
       | How's that possible it managed to fly with only one engine ?
        
         | philjohn wrote:
         | Read up about ETOPS, which is what allows twin engined aircraft
         | to fly long stretches over water.
        
         | minxomat wrote:
         | That is not a problem.
        
         | xnx wrote:
         | Amazingly, I believe planes are designed/certified to do
         | everything (e.g. take off fully loaded) with only a single
         | working engine.
        
           | pintxo wrote:
           | And if they loose the remaining one, all goes south:
           | https://www.youtube.com/watch?v=zn1a2lSk_UI&feature=emb_logo
        
             | NikolaeVarius wrote:
             | No, planes glide just fine. That plane simply did not have
             | enough altitude, or lift considering the bank angle to
             | recover
        
               | pintxo wrote:
               | Their problem really was a lack of situational awareness
               | / crew resource management.
               | 
               | As they did shut down their perfectly well working engine
               | instead of the broken one. Obviously that's not improving
               | your situation in any way.
        
             | shiny wrote:
             | Not if you have Sully in the cockpit [1]. They can still
             | glide.
             | 
             | [1]: https://en.wikipedia.org/wiki/Chesley_Sullenberger
        
               | saagarjha wrote:
               | Not very well, though.
        
               | ceejayoz wrote:
               | Well enough.
               | 
               | https://en.wikipedia.org/wiki/Gimli_Glider
               | 
               | > In 10 nautical miles (19 km; 12 mi) the aircraft lost
               | 5,000 feet (1,500 m), giving a glide ratio of
               | approximately 12:1 (dedicated glider planes reach ratios
               | of 50:1 to 70:1).
               | 
               | > Air Canada Flight 143 came to a final stop on the
               | ground 17 minutes after running out of fuel.
        
           | londons_explore wrote:
           | Not true - most planes must abort the takeoff if any engine
           | fails below a certain speed.
        
         | [deleted]
        
         | S_A_P wrote:
         | Planes _must_ be able to do this to be certified.
        
           | ceejayoz wrote:
           | Well, assuming they have two+.
           | 
           | A C-172 isn't gonna fly too far with an engine out.
        
             | tialaramex wrote:
             | But, the pilot should be assuming that its single engine
             | will fail, and prepared for that eventuality when it's most
             | likely, which is during take off.
             | 
             | Every flight the person sat at the controls ought to
             | already know, before they're accelerating down the runway,
             | what they're going to do when (not if, if you keep flying
             | these little prop planes you've got to assume it'll happen
             | eventually) the engine quits. What's beyond that airfield
             | fence? A carpark? A pond? A school?
             | 
             | The "impossible turn" (landing where you took off) might
             | legitimately be a valid strategy for your failure in some
             | circumstances if you've thought it through, but if you're
             | doing it because you had no plan you're very likely to find
             | out why they call it that.
        
         | JCM9 wrote:
         | It's designed to fly with only one engine. Not with great
         | performance, but it will stay in the air. Routine procedure for
         | twin engine aircraft.
        
           | xvf22 wrote:
           | Not only fly but climb.
           | 
           | Commercial aircraft are required to fly safely should one of
           | the two engines fail at any point of the flight, including
           | takeoff at speeds beyond v1.
        
             | snuxoll wrote:
             | For the uninformed:
             | 
             | V1: Speed at which the take off attempt should no longer be
             | aborted
             | 
             | Vr: Speed at which the plane should be pitched up (rotated)
             | 
             | V2: Speed at which the plane can safely climb with one
             | engine
             | 
             | If an engine fails after V1 the runway is supposed to have
             | sufficient length that you can hit Vr, rotate, and be 35
             | feet off the ground and traveling at V2 before you run out
             | of tarmac even with a single engine.
        
               | xvf22 wrote:
               | Fair enough and my memory may be fuzzy but I see quite a
               | few references to V1 as being the minimum single engine
               | takeoff speed.
               | 
               | https://skybrary.aero/bookshelf/books/493.pdf (page 2)
        
               | zerocrates wrote:
               | I don't have any specialist knowledge here, but that
               | seems to make sense. If you're under V1 then you can
               | still abort takeoff. Having that be the _minimum_ for
               | single-engine takeoff essentially sets up the rule that
               | if you lose an engine while you _can_ safely abort, then
               | you must.
        
               | snuxoll wrote:
               | It's kind of poorly worded. Hitting V1 means you are
               | committed to taking off, single engine failure or not -
               | but you HAVE to reach V2 to safely climb on one engine.
               | 
               | This should happen within moments of hitting Vr, but
               | being single-engine after V1 means you went from hitting
               | Vr halfway down the runway to potentially doing so at the
               | ass-end of your minimum runway length. This means you
               | have basically no room for any pilot error or other
               | failures, and why engine failure on take-off is routinely
               | rehearsed.
        
           | NovemberWhiskey wrote:
           | ... and to fly that way for quite some time with high
           | confidence of success.
           | 
           | If you think about it: this aircraft was flying to Hawaii;
           | after crossing the west coast, it would be flying almost
           | 2,500 miles over the ocean to get there.
           | 
           | If you lost the engine halfway there (instead of soon after
           | takeoff), you'd either have to turn around and fly back
           | toward California or continue onwards; which is almost a
           | three hour flight.
           | 
           | The concept is called ETOPS for Extended Twin Operations; and
           | the Boeing 777 was the first twin-engine aircraft rated to do
           | this (fly up to three hours for the nearest available
           | airport).
        
         | mhh__ wrote:
         | Lesson's learned in the aviation industry are worth their
         | weight in blood, so the engineers have learnt the hard way to
         | plan for every reasonable eventuality.
        
           | [deleted]
        
         | chrisseaton wrote:
         | Why do you think it has two engines in the first place?
        
           | Sn0wCoder wrote:
           | Come on, we all know so they can go faster.
        
             | msla wrote:
             | If that was the reason, they'd paint it red!
        
             | chrisseaton wrote:
             | They could go faster with a single larger engine. Why do
             | you think they went with two engines instead of a single
             | larger engine? Redundancy.
        
               | ghaff wrote:
               | Not clear to me that you'd design a commercial turbofan
               | aircraft with one engine if you eliminated reliability
               | requirements. You need to feed air to the engine and, to
               | the degree you have wings, might as well have 2 engines.
        
               | chrisseaton wrote:
               | The idea that the engines need to sit on the wings like
               | they do is something seems important, because it's so
               | often done, but is actually not necessary. You can put a
               | single engine in the tail, or on top of the cabin, or on
               | the top of the cockpit, or underneath. They go on the
               | wings because when you need two (for redundancy) it's a
               | good place to put them for balance, and because it makes
               | them nicely accessible for maintenance.
        
               | TazeTSchnitzel wrote:
               | Trijets are cool!
        
               | dehrmann wrote:
               | > it's so often done
               | 
               | The MD-80 had two rear engines and was a fairly popular
               | plane. A lot of smaller jets still have rear engines,
               | too.
        
               | ghaff wrote:
               | The MD-80 (and 727) were old turbojets though. Probably a
               | lot harder to come up with a practical tailmounted design
               | with a turbofan although I'm open to it being possible to
               | mount one turbofan above the fuselage.
        
               | chrisseaton wrote:
               | Not sure what you mean? I didn't say it was always done.
               | In fact the point I was making was that it wasn't always
               | done. I gave my own counter-examples. It's just when
               | people look at modern planes they always see two engines
               | and think that's the way it has to be. It clearly isn't.
        
               | ghaff wrote:
               | Of course military aircraft have different requirements
               | (and many have just one engine in the tail). Certainly
               | I'm not enough of an aero/astro engineer to know if,
               | positing a perfectly reliable engine, you'd mount just
               | one somewhere on the fuselage.
        
               | andrewflnr wrote:
               | Citation needed. It's not at all obvious that a single
               | huge engine is in any way better than two for a given
               | speed.
        
               | Sn0wCoder wrote:
               | Note sure this is reliable source but " In general, twin
               | engine aircraft allow for faster speeds, and faster
               | pickup..."[1]
               | 
               | 1 - https://www.vikingair.com/twin-otter-
               | information/twin-otter-...
        
               | NikolaeVarius wrote:
               | This is basic aeronautical engineering. Barring the need
               | for redundancy, turbofans are most efficient and quieter
               | with larger intake sizes, the main limiting factor being
               | fan tip speed.
               | 
               | This is the reason that the 737 had the MCAS stuff. They
               | increased the size of the engine that caused ground
               | clearance problems, which required shifting them.
        
               | chrisseaton wrote:
               | > Citation needed.
               | 
               | Look up 'ETOPS'.
        
               | mannykannot wrote:
               | While redundancy makes it a moot issue, if I am not
               | mistaken, 777s already use some of the most powerful
               | engines available. As for how fast they fly, I believe it
               | is mostly set by the speed of sound.
        
               | [deleted]
        
               | chrisseaton wrote:
               | Yes they use two of the most powerful engines... and just
               | one of those is more than enough to fly the plane just
               | fine almost as fast as they are allowed to... so why else
               | would they have two of them if not redundancy?
               | 
               | Fundamentally people can look it up themselves - 'ETOPS'
               | - the redundancy requirement is a written regulation.
        
               | mannykannot wrote:
               | I think it should be obvious that I am responding to the
               | claim "they could go faster with a single larger engine."
               | no-one is arguing against redundancy (in which matter,
               | ETOPS is just one aspect.)
        
               | [deleted]
        
               | chrisseaton wrote:
               | _If_ they needed to go faster, they could do that with a
               | single larger engine if they wanted to (which they may
               | have to develop.) But they don 't, because they're
               | limited as you've explained.
               | 
               | > no-one is arguing against redundancy
               | 
               | Sn0wCoder said they reason they had two engines was to go
               | faster and not redundancy, and m00dy thinks they can't
               | fly without two engines.
        
               | mannykannot wrote:
               | Point taken that some people had mistaken ideas about
               | twin-engine airplanes, but those mistakes are most
               | straightforwardly resolved by the redundancy
               | consideration alone, which dominates other issues.
               | 
               | > _If_ they needed to go faster, they could do that with
               | a single larger engine if they wanted to _(which they may
               | have to develop.)_
               | 
               | Plus a significantly different airframe and perhaps
               | engine intakes to deal with the transonic issue that I
               | also mentioned. It is an idea that bubbles up perennially
               | [1], but so far, the economics have ensured that it
               | doesn't go much beyond the concept stage.
               | 
               | This has become rather silly, but it seques into a
               | related issue: It seems to me that fan-blade failure
               | incidents (or at least uncontained fan-blade failure
               | incidents) have increased in frequency in the last few
               | years. If so, maybe this is a sign that we are already
               | pushing a bit too hard on the limits of current
               | technology?
               | 
               | [1] https://www.boeing.com/features/2019/01/spreading-
               | our-wings-...
        
         | btgeekboy wrote:
         | The other engine provides enough thrust to keep the plane
         | airborne. The pilots (and likely other onboard systems)
         | compensate for the asymmetric thrust with the rudder.
         | 
         | As scary as it looks, this is one type of event that pilots
         | routinely train for, both to get their initial multi-engine
         | certification, and on their airlines' simulators.
        
           | gshubert17 wrote:
           | > The other engine provides enough thrust to keep the plane
           | airborne.
           | 
           | We could hear the remaining (loud) engine as the plane flew
           | over. Our house is less than 2 miles from where the parts
           | landed and right under its flight path.
           | 
           | The boom just before that sounded like a sonic boom and shook
           | our house perceptibly.
           | 
           | There's been some property damage (a smashed truck top and a
           | big hole in a roof) but no reports of injuries to this time
           | (18:45 Mountain time).
        
           | londons_explore wrote:
           | They happen pretty frequently... Just normally they don't
           | look as visually spectacular as this.
        
         | danaliv wrote:
         | To a first approximation, if it takes X thrust to stay aloft,
         | the engines produce a combined total of more than 2X, and there
         | is a speed above which the rudder produces enough aerodynamic
         | force to maintain directional control.
         | 
         | If you want to get into the nitty gritty, look up multiengine
         | airplane type certification requirements.
        
       | ficklepickle wrote:
       | This is quite timely, I was just looking at similar incidents
       | yesterday.
       | 
       | It is somewhat similar to a BA A319 flight where the engine
       | covers weren't latched. They immediately ripped off, taking out
       | one of the engines. Similar footage of exposed engine internals.
       | Safely landed after dumping fuel. That one led to a redesign of
       | the latches.
       | 
       | Another very interesting one I found was a prop going through the
       | fuselage of a DC-8 in Edmonton in 2014. A passenger was inches
       | from being killed.
       | 
       | A319: https://avherald.com/h?article=462beb5e
       | 
       | DC-8: https://avherald.com/h?article=47cee08a&opt=0
        
         | midasuni wrote:
         | The BA pilot headed across central london back to heathrow,
         | dropping debris along the way, rather than land at stansted -
         | avoiding built up areas, but costing BA more.
        
       | hntestacc wrote:
       | This is a test. If you see this, please pass through.
        
       | martyvis wrote:
       | Juan Browne, a 777 pilot, always gives a great citizen reporter /
       | industry insider take on these incidents
       | https://youtu.be/Tkieg1ZFcPE
        
       | JCM9 wrote:
       | The press will make a big deal out of this because of the
       | spectacle of parts falling on people's lawns... but other than
       | that this looks like a fairly routine engine out situation. Nice
       | job by the crew.
        
         | choeger wrote:
         | And by "routine" you mean "standard when you lose an engine"
         | not, "we lose an engine every other Friday", right? Because
         | starting in a plane _is_ kind of scary enough, all things
         | considered.
        
         | pedrocr wrote:
         | Uncontained engine failures are a big deal. Exactly because
         | they're a risk to the plane, as debris can cause other
         | failures, and a risk to people on the ground. Engines are
         | specifically tested to see if they can contain these failures.
         | This doesn't seem routine at all.
        
           | JCM9 wrote:
           | Yes, hence why I said the press will focus on this because of
           | parts raining down. An airliner having an engine issue and
           | returning single engine though is a routine thing... usually
           | without missing parts.
        
             | pedrocr wrote:
             | Uncontained engine failures are cause to ground whole
             | fleets of planes, even if the resulting emergency ended up
             | mild. You're downplaying it way too much.
        
               | leesalminen wrote:
               | Also a similar event has happened before on a United
               | Boeing 777-200 en route to Hawaii from Denver in 2016.
               | 
               | http://avherald.com/h?article=4999bec5
               | 
               | Also another similar event on a United Boeing 777-200 en
               | route to Hawaii in 2018.
               | 
               | http://avherald.com/h?article=4b4e8ca7
        
             | Cederfjard wrote:
             | When you say things like "the press will make a big deal
             | out of this", one might take it to be implied that they
             | shouldn't. I hear you that returning with one engine might
             | be fairly routine, but isn't it fair to make a thing out of
             | large chunks of metal falling from planes over populated
             | areas?
        
           | s1artibartfast wrote:
           | They are both a big deal and expected. 3-4 happen per year
           | and this is why pilots train for them.
        
           | Waterluvian wrote:
           | I think you're both right. I think it's routine in that once
           | the disaster occurred, the emergency procedures to get the
           | plane safely landed were executed without issue.
           | 
           | I'm guessing kind of like firefighters describing a call as a
           | routine, by the books operation.
        
           | rectang wrote:
           | Uncontained engine failure caused the 1989 Sioux City crash
           | of United 232, when debris took out all three hydraulic
           | lines.
           | 
           | https://en.wikipedia.org/wiki/United_Airlines_Flight_232#Tak.
           | ..
        
       | leemailll wrote:
       | Video of flight track and atc recording :
       | https://www.youtube.com/watch?v=G7-zh7Sebr8
        
       | WaitWaitWha wrote:
       | Qs:
       | 
       | Anyone tracking the quantity of these events as it relates to the
       | pandemic? Has there been an uptick? If so, can it be correlated
       | with maintenance crew availability?
        
       | waynesonfire wrote:
       | Pretty nice view of the burning engine from inside the plane,
       | 
       | https://twitter.com/JacdecNew/status/1363245241109782528?ref...
        
         | cuechan wrote:
         | Reading this sentence makes me uncomfortable
        
       | chovybizzass wrote:
       | ...aaaaaaand that's why i refuse to fly.
        
         | midasuni wrote:
         | You're more likely to die on the drive to the airport than on
         | the plane.
         | 
         | Irony means you'd personally stay at home, but then have an
         | engine cowling land on you in your garden.
        
         | voiper1 wrote:
         | It sounds terrifying, but even so it landed safely.
         | Statistically, flying is safer than car travel...
        
         | technicolorwhat wrote:
         | Fellow scared dude here. I still fly even though I am
         | terrified. Its annoying but don't let it stop you from seeeing
         | all the beautiful places in the world. Usually I just get
         | absolutely drunk, fake being sober going trough control and
         | unfortunately that kinda works. Annoying hangover though.
         | hahah. Wish I could do sth about it!
        
       | larkinrichards wrote:
       | I really appreciate focused news sites like avherald. Just the
       | facts, a collection of photos and videos, straightforward.
       | 
       | The video of the landing & the passengers cheering--- that huge
       | sigh of relief. Brings a smile to my face.
        
         | IgorPartola wrote:
         | What, you don't like the anchor people on TV asking each other
         | how they feel about every piece of news and making horrible
         | puns at every opportunity? Or having expected announcements be
         | reported as BREAKING NEWS?
        
           | m463 wrote:
           | How about the 1000 watermarks on every resampled movie and
           | jpg?
        
           | secfirstmd wrote:
           | As a European who tuned in to US News for the US election I
           | thought that was crazy.
           | 
           | I'd watch a few of the right media orgs to see what they were
           | saying and then stay on CNN/MSNBC etc for most of it. It's
           | mad how so much of it every hour was essentially people just
           | regurgitating stuff to fill the time. I mean OK what's
           | happening is important but if you can't fill the airtime why
           | not shift to other news (as in everything else happening in
           | the world - HK democracy leaders were arrested during that
           | time and I don't remember any proper mention through days
           | upon days).
           | 
           | Also the fake breaking news thing was stupid. The amount of
           | times I'd turn up Wolf Blitzer or something because I would
           | hear breaking news announcements in the background and
           | thinking like you'd get at the BBC, Channel 4, RTE, France 24
           | Al Jazeera English, etc that something important was
           | happening. Only to find breaking news was basically just
           | random scheduled things or just regurgitation of what
           | happens. Here Sky News is bad for playing things up but
           | nowhere near as bad as any of them.
           | 
           | News on the right in the US is awful but the Left isn't much
           | better unfortunately. What do people watch that's in the
           | Centre and actual news rather than hyperbole? PBS?
        
             | ficklepickle wrote:
             | Fear makes things memorable, makes it hard to turn away.
             | It's an evolutionary thing.
             | 
             | If my mom calls me after she has been watching that shit,
             | she sounds strung out on stimulants. Agitated, easily
             | angered. She is normally a calm, fairly rational person.
             | 
             | It's fear mongering and it exists because it is effective.
             | If one gets caught up in it, it can be hard to take a step
             | back and realize what is going on. One might hear
             | rationalizations like "I have to stay informed" or "it is
             | related to my work". Very similar behaviour to other
             | addictions.
             | 
             | I'm reminded of Tool lyrics:
             | 
             | "Stare like a junkie Into the TV Stare like a zombie While
             | the mother Holds her child Watches him die Hands to the sky
             | crying Why, oh why? 'cause I need to watch things die From
             | a distance Vicariously I, live while the whole world dies
             | You all need it too, don't lie
             | 
             | Why can't we just admit it?"
        
               | nyolfen wrote:
               | reminded me of a post i saw earlier today:
               | 
               | > Occasionally watching terrestrial/mainstream TV is
               | equivalent to dipping your head back into the Cave,
               | except, the shadows no longer make any sense, and yet
               | everyone is entrapped by them. It's noisy, bright and
               | hellish, you can't go back, you're in a different world
               | now.
               | 
               | once you can curate information feeds and investigate
               | topics in depth on demand, not to mention adblocking,
               | watching tv at all feels like a psychic assault
        
             | umanwizard wrote:
             | All US TV "news" is intolerable garbage, but since the US
             | is the global cultural hegemon, plenty of foreign media
             | outlets cover our news. Almost any well-respected European
             | broadcaster is a better source for US political news than
             | any in the country.
             | 
             | Newspapers are better than TV: the New York Times and Wall
             | Street Journal are both much less sensational than any of
             | the broadcasters.
        
             | Zelphyr wrote:
             | They figured that little "Breaking News Alert!" out during
             | 9/11, during which it was useful, but not at all after. I
             | remember when Jason Priestly got into a car accident and
             | they started throwing those alerts up. I realized then,
             | "ok. Now they've jumped the shark"
             | 
             | The only thing that amazes me at this point is that it is
             | apparently still effective enough that they keep doing it.
        
             | ptero wrote:
             | If you want news on a hot button topic it is usually better
             | to watch it reported from far away. Less attachment leads
             | to more information and less spin.
             | 
             | Thus I would read US election news on European or Asian
             | news sites, Brexit from Asia, etc. Just my 2c.
        
             | sneak wrote:
             | I tried to do that, but even MSNBC these days seems to have
             | fallen to hyperpartisan agitprop.
             | 
             | I check nyt and cnn (both with a large grain of salt)
             | periodically (~1x per week, for 5-10 minutes?) but
             | unfortunately neither of those are quite as reliable as one
             | would hope.
        
               | IgorPartola wrote:
               | Reliable by what metric?
        
               | sneak wrote:
               | https://lawandcrime.com/awkward/torture-is-a-legal-term-
               | why-...
        
             | IgorPartola wrote:
             | My favorite is lately CNN posts an article outlining what
             | the new administration is planning on doing the next few
             | days. Then when they do every part of it, they post a
             | BREAKING NEWS article about that item. Like, I, a very
             | causal reader of the news, knew it was going to happen. Who
             | is it a surprise to?
        
             | mensetmanusman wrote:
             | If you're smart you aren't watching anything, especially
             | since we know now that the more you watch the less in tune
             | with reality you are.
        
             | doomrobo wrote:
             | I think the answer is don't watch TV news if you can help
             | it. If 100% of their revenue comes from ads, then their
             | incentives are clear: keep you watching no matter what.
             | 
             | The way I see it, written news at least has a wider range
             | of options, and the subscription model means they have
             | slightly less incentive to be so manipulative.
        
               | secfirstmd wrote:
               | Yep agree absolutely. I probably read 5-10 different
               | global media a day normally online. I rarely watch TV
               | news but it was sort of an experiment I guess. Wow some
               | of the stuff on places like Newsmax made Fox look like
               | The Guardian.
        
               | bobthepanda wrote:
               | Newsmax and OAN are notorious for extremely slanted
               | coverage.
               | 
               | The Guardian has a slant, but nearly every news outlet
               | will have some slant, either by coverage or through
               | omission. But it's certainly a lot worse at Newsmax and
               | OAN.
               | 
               | EDIT: accidentally said "doesn't have"
        
               | joshuahughes wrote:
               | The Guardian doesn't have a slant? You might want to
               | reconsider that...
               | 
               | "the Guardian is seen as Britain's most left-wing
               | newspaper"
               | 
               | https://yougov.co.uk/topics/politics/articles-
               | reports/2017/0...
        
               | secfirstmd wrote:
               | I love The Guardian, it's the closest to my views but it
               | most it definitely has a slant. I don't mind that. It's
               | news is newsy and it's commentary is openly left wingish.
        
               | AnthonyMouse wrote:
               | > I love The Guardian, it's the closest to my views but
               | it most it definitely has a slant. I don't mind that.
               | 
               | You have to be careful with this though.
               | 
               | Once upon a time people said this and what they meant was
               | essentially selection bias. So they would report all the
               | major stories, but when choosing the minor stories to
               | fill the rest of their space, it would be stories
               | favorable to one side or the other. And the stories they
               | did cover were covered fairly.
               | 
               | The common practice now is purposely misleading people.
               | Omitting key details of a story or selectively quoting
               | people out of context to change the meaning of what they
               | said.
               | 
               | Probably the canonical example of this is when people
               | were protesting the taking down of statues of members of
               | the confederacy. Some but not all of the protestors were
               | neo-nazis. Others make the case that people are more than
               | the worst thing they ever did, or that taking down the
               | statues is an attempt to memory hole what happened.
               | 
               | Trump got in front of a camera and said "very fine people
               | on both sides." In the same interview he makes explicit
               | that he's not talking about the racists and condemns
               | them:
               | 
               | https://www.politifact.com/article/2019/apr/26/context-
               | trump...
               | 
               | That quote was widely taken out of context for years to
               | imply that he was calling the racists "very fine people."
               | 
               | It's not the same thing as just choosing which minor
               | stories to cover. It's dishonesty.
        
               | tialaramex wrote:
               | Yup, its nickname ("Grauniad") may be about its
               | historically awful proofreading but it's just as
               | politically off-centre as say the Daily Telegraph
               | ("Torygraph") which gets an explicit accusation of
               | political bias right in the nickname.
               | 
               | Every publication is going to have _at least_ editorial
               | bias in what opinions get written, and what stories are
               | covered, at all or in greater profile.
               | 
               | Private Eye - a famous British satirical magazine - has
               | an entire section ("Street of Shame" referring to Fleet
               | Street) about the worst of this (e.g. newspapers taking
               | long term advertiser money and then conspicuously failing
               | to mention grave problems at the advertised business),
               | but it too has its share of blind spots, most famously it
               | took Wakefield's side on the MMR vaccine claims long
               | after mainstream opinion had shifted to focus on the
               | apparent abuse and profiteering by Wakefield, and even
               | after he was struck off it continued to slow walk any
               | suggestion that its coverage had been wrong or
               | misleading. Its coverage for the present pandemic has
               | been... less than stellar also, except in the sense that
               | it criticises the government for doing a bad job, an open
               | goal sometimes missed at a few of the most right-wing
               | papers.
        
               | bobthepanda wrote:
               | That was actually a typo. Need to proofread before I
               | post, apparently.
        
             | nowandlater wrote:
             | The PBS News Hour is pretty solid,
             | https://www.youtube.com/user/PBSNewsHour
             | 
             | The weekly videos from Robert Wright & Mickey Kaus on
             | Bloggingheads Tv is pretty good too.
             | https://www.youtube.com/channel/UCeamuoYuBeRnRRbmq5CmjVg
        
               | systematical wrote:
               | PBS news hour is a total of 6 hours per week (weekend
               | shows are 30 minutes each). In those 6 hours, they cover
               | more than any one of the 24 hour news networks. You're
               | killing your mind watching 24 hour news networks, any of
               | them.
        
               | secfirstmd wrote:
               | Thanks, yeh I think when I want US News I might look at
               | those instead
        
               | systematical wrote:
               | Catch live and past episodes on YouTube.
        
               | heavyset_go wrote:
               | PBS stations also run local news programs, too. The ones
               | that I've watched have always been great compared to most
               | entertainment news programs.
        
             | laurent92 wrote:
             | Tweets now often start with the 3 gyrophares then "breaking
             | news urgent!!!"
             | 
             | It is highly stressful. A good tip is to write "Breaking",
             | "Alert" and "Urgent" as spam words in the Twitter
             | administration, so all tweets containing it will be hidden
             | (or leave them, to ensure the Twitter experience is as bad
             | as possible until you hate opening it).
        
             | hervature wrote:
             | Reuters TV, 30 minutes every day, about 15-20 stories from
             | around the globe but focusing on US. Read by a faceless
             | person in an emotionless voice. That's what I do.
        
             | marshmallow_12 wrote:
             | i like that they keep such a positive tone of voice. I get
             | the impression they delight in sharing "bad" news since it
             | invariably can be blamed on whichever party their outlet
             | opposes.
        
           | fireattack wrote:
           | Am I the only one who get really tired of this kind of
           | sarcasm?
        
             | wl wrote:
             | The same point could be made without sarcasm. Would you
             | object, then?
        
               | afavour wrote:
               | Without the sarcasm it would just be restating exactly
               | what the parent comment said.
               | 
               | I agree with the OP: if we disapprove of posts that only
               | say "same" or "me too" we should probably also discourage
               | posts that dress exactly that in sarcasm.
        
               | Sebb767 wrote:
               | > if we disapprove of posts that only say "same" or "me
               | too" we should probably also discourage posts that dress
               | exactly that in sarcasm.
               | 
               | I fully agree on this point, but the comment in question
               | (sarcastically) criticized certain behaviours ("asking
               | each other how they feel about every piece of news" and
               | "making horrible puns at every opportunity"), so I don't
               | think it fully falls under that threshold.
        
               | dmos62 wrote:
               | Sarcasm is also somewhat passive-aggressive.
        
           | TwoNineFive wrote:
           | HO HO THAT'S RIGHT BOB
        
           | xur17 wrote:
           | I distinctly recall signing up for "breaking news alerts" a
           | few days after 9/11. I figured if something major happened,
           | it would be nice to receive a notification about it. I
           | quickly learned that my definition of breaking news was
           | dramatically different from that of the news..
        
             | midasuni wrote:
             | As far as I'm concerned breaking news should be stuff that
             | interrupts non news channel output. Lost that argument
             | decades ago though.
        
           | gowld wrote:
           | No, and we don't appreciate sarcastic imitations either, as
           | that brings unpleasantness here while we are appreciating a
           | better environment.
        
           | derefr wrote:
           | I would be intrigued to see a news site where only news
           | interesting enough to "speak for itself" without
           | editorialization makes the cut to publish.
           | 
           | It'd probably be pretty slow to update, but that's be fine by
           | me.
        
           | dehrmann wrote:
           | Don't forget the quasi-experts they bring on to fill even
           | more airtime.
        
           | malandrew wrote:
           | Appropriate: https://www.smbc-comics.com/comic/reactive
        
           | Fogest wrote:
           | BREAKING NEWS: More people died of COVID today. I see see
           | often headlines in my Google news feed saying something along
           | those lines.
           | 
           | I've stopped clicking on YouTube videos that give me no idea
           | what they are going to be in the thumbnail/title. For example
           | on Linus Tech Tips second channel ShortCiruit a good chunk of
           | their videos do this. Latest one from 3 years ago in my sub
           | box "I almost hurt myself open this...." and the thumbnail is
           | him maybe holding a big TV with a game on the screen. I can't
           | tell if it's a big monitor, a tv, or if the video will be
           | about what's on the screen in the thumbnail. I wish that
           | videos/news/blogs that use titles like this could also just
           | tack something on the end in brackets saying a couple words
           | about what it's actually talking about.
           | 
           | Too often I'm having to fall prey to the clickbait just to
           | see if maybe the video will interest me or not. More often
           | than not it doesn't and I just wasted time.
        
             | milankragujevic wrote:
             | Offtopic to OP but regarding Linus Tech Tips:
             | 
             | I also stopped watching 90% of all LMG (his company) videos
             | (on all their channels) because of the clickbait forcing me
             | to click onto things that I am not interested in, only to
             | quickly leave the video. I am not going to watch what I
             | don't want to watch whether it has a clickbait thumbnail
             | and title or not, so they just annoy me more with this. I
             | have not voiced my opinion for two reasons: 1) it's a
             | really common opinion, Linus is aware of it and this style
             | is obviously good for business since they kept it, 2) fear
             | of intense backlash from the fan community.
             | 
             | So yeah, got that off my chest.
        
               | eptcyka wrote:
               | There's a fan community? I was always under the
               | impression that his videos served as glorified ads for
               | consumer tech. The technical insight delivered was skin
               | deep. Didn't he brag about a 20 drive NAS one week only
               | to cry about the raid0 config dying and taking down a lot
               | of their footage the next week?
        
               | exikyut wrote:
               | I'm not sure if you're referring to
               | https://www.youtube.com/watch?v=gSrnXgAmK8k ("All of our
               | data is gone"), but in any case, I've heard references to
               | ZFS in later videos so yeah, the situation's probably not
               | quite that insane now.
               | 
               | That video is technically hilarious though, it TL;DRs as
               | "download Ubuntu-based USB image provided random RAID
               | recovery company, boot USB and provide said company
               | headless SSH to broken system"... at one point in the
               | video I remember Linus talks to another recovery company
               | about the process and the guy pretty much went
               | "...O.o..." which IMO sums my own opinion up, lol
        
               | spyridonas wrote:
               | Yeah but the actual raid card got kaput. Interesting
               | recovery process. (Basically read the firmware and flash
               | to another card as far as i remember)
        
               | zucker42 wrote:
               | I don't think it was Raid 0 if you're talking about the
               | time a long time ago they nearly lost data. If I recall
               | correctly, the data was in Raid 6, but there was no
               | external backup.
        
               | geerlingguy wrote:
               | Video for those interested:
               | https://www.youtube.com/watch?v=gSrnXgAmK8k
               | 
               | Actually a pretty good telling of a story all too common
               | for those tasked with handling precious data.
        
               | Fogest wrote:
               | Yeah it seems like almost all of their videos are using
               | clickbaity titles now especially on the secondary
               | channels like ShortCiruit. My viewership of their videos
               | has really dropped. I'm sure they have seen results from
               | gaming the recommended videos but I'd be interested to
               | see if it has affected how many average viewers they get
               | from the subscribed people.
               | 
               | Man first you had to get AdBlock, and recently it feels
               | necessary to use SponsorBlock, and now it feels like
               | there needs to be a new one called ClickBaitBlock which
               | maybe swaps the video titles for a user voted new title
               | similar to SponsorBlock. I'd actually install it if it
               | existed.
        
               | ajayyy wrote:
               | Not the same as what you wanted, but this one can help:
               | https://github.com/pietervanheijningen/clickbait-remover-
               | for...
               | 
               | I do think it would be cool though to expand SponsorBlock
               | into more crowd-sourced things, since there is already a
               | community of people willing to help.
        
               | sillysaurusx wrote:
               | That's quite a name! I thought it was a chrome extension
               | at first. Thanks for pointing it out.
        
               | Fogest wrote:
               | Unfortunately this one seems to just change the casing of
               | the title and then grabs a frame from the video to use
               | for the thumbnail. I find that the thumbnail at least
               | sometimes contains something useful whereas this may be
               | counterproductive.
               | 
               | With YouTube you can hover over the video thumbnail and
               | see a short preview of the video play so that aspect is
               | already kinda covered by YouTube itself.
               | 
               | It's definitely getting closer to what I was talking
               | about but unfortunately falls short.
        
               | halefx wrote:
               | I watch LMG content because I find it more entertaining
               | than anything else on YouTube, and I'm not even a PC
               | gamer. I rarely look at the poster or video title at all
               | before watching, I just queue the new items immediately.
        
               | opensmtpd wrote:
               | I'm on the same boat. I stopped watching their videos
               | after I started to feel more and more videos were made
               | just for the sake of making more videos. Every time I
               | bite and watch through, I realize I haven't gained any
               | fun, information, nor education and just wasted 10
               | minutes and 1 second of my time. I don't think it's just
               | LTT. I feel that more and more channels are going this
               | way.
        
             | banana_giraffe wrote:
             | I'm in the same boat .. actually, I'm more set in my ways,
             | if the title doesn't tell me what it's about, I don't
             | bother looking at the thumbnail. Here are some titles from
             | recent videos:                   I REALLY Love Building
             | Computers!!         Never seen one of these before...
             | Sorry. Your gaming laptop sucks now.         Maybe
             | upgrading is pointless.....         Linus was right.
             | 
             | It's such click-bait, and so annoying.
             | 
             | It's sad about LTT too. I can't find it now, but I saw a
             | video of his talking about this. He doesn't actually like
             | these titles, but claims to have proof they improve
             | viewership counts, so in his quest to optimized for higher
             | and higher counts, he annoys some long time viewers. Can't
             | blame him if it works, but I do wonder if it'll be self-
             | defeating in the end.
        
               | garaetjjte wrote:
               | >but I saw a video of his talking about this. He doesn't
               | actually like these titles, but claims to have proof they
               | improve viewership counts
               | 
               | Veritasium also had video on this topic:
               | https://youtu.be/fHsa9DqmId8?t=1041
        
               | bilegeek wrote:
               | Here's the video where Linus goes into it:
               | https://www.youtube.com/watch?v=DzRGBAUz5mA
               | 
               | I'll give him credit for being straight about it.
        
               | Fogest wrote:
               | Oh yeah I can't really blame them. I don't feel upset
               | personally at them for it, I feel upset at YouTube for
               | making these clickbaity titles do better than more normal
               | titles. It's unfortunate because this is likely actually
               | just machine learning realizing that a lot of us humans
               | use our pea brains to decide if we want to watch a video
               | and thus often times those clickbait videos get more
               | clicks. But I really wished they put some manual tweaks
               | in place to make the user experience a bit more enjoyable
               | and stop promoting those clickbait videos in
               | recommendations so that creators didn't feel the need to
               | do it.
               | 
               | I mentioned it in my other comment, but it feels like we
               | need a ClickBaitBlock similar to SponsorBlock which uses
               | user generated timestamps to skip sponsor blocks in
               | videos. Could be a user generated/voted on new title that
               | gets used. I'd actually use something like that too. It
               | allows creators to play their YouTube game, but also us
               | avoid the game if we choose to. Hell the extension could
               | even support allowing the video creator to submit their
               | own alternative titles. It would be a neat way to beat
               | YouTube at it's own game.
        
               | jrockway wrote:
               | I am interested in how he A/B tests these things. I've
               | never seen non-clickbait LMG videos, so if they're
               | constantly testing they must not be up for long. Or they
               | test on their forums or something like that.
               | 
               | (I know it sounds like I'm confirming the theory that
               | videos don't get recommended if they're not clickbaity,
               | but I only rarely get LTT recommendations in general. I
               | do specifically go to the channel and look for things to
               | watch every so often, however, and it's there that I
               | don't see any non-clickbait test versions.)
        
               | mc10 wrote:
               | They often change the titles of their videos, sometimes
               | multiple times. Not sure if that counts as "A/B testing"
               | though.
        
               | wyxuan wrote:
               | They don't do the clickbait titles or thumbnails on
               | floatplane(their in house version of youtube), and will
               | often edit the titles if it's too clickbait-ey
        
               | Fogest wrote:
               | Does something like that include their videos from their
               | other channels too?
        
               | easton wrote:
               | All of their channels are in the same LTT page on
               | floatplane, although apparently they will be moved to
               | other pages later.
        
         | mherdeg wrote:
         | If you value the work you should definitely donate some money
         | (PayPal link in the sidebar on every page on avherald.com). I'm
         | pretty sure it's still just one person (Simon Hradecky) doing
         | outstanding editorial work.
        
         | vmception wrote:
         | Any links to the passenger livestreams?
        
         | divbzero wrote:
         | The straightforward captions are also delightful:
         | 
         | > _The aircraft seen in flight_
         | 
         | > _The engine inlet in a garden_
         | 
         | > _Engine debris on the Broomfield soccer field_
        
           | benatkin wrote:
           | Counterpoint to the last two:
           | 
           | - it's just a front yard (It would make a good CAPTCHA
           | question - select all photos of gardens. Anyone choosing a
           | photo of this yard before the debris landed there would
           | fail.)
           | 
           | - there's more than one soccer field in Broomfield
        
             | gdavisson wrote:
             | I'm pretty sure "garden" is being used in the British
             | sense, roughly corresponding to "yard" in American English.
        
           | artificial wrote:
           | It would be amusing if it turned out to be machine vision
           | transcriptions.
        
             | pixl97 wrote:
             | "We are unable to determine if this is a puppy or a
             | blueberry muffin"
        
         | valuearb wrote:
         | Michaela's video is terrifying.
        
         | nickt wrote:
         | Just read the comments, that'll fix your optimism!
        
       | [deleted]
        
       | paulmd wrote:
       | That's not typical, I'd like to make that point. There are a lot
       | of these engines going all over the world all the time and very
       | seldom does anything like this happen.
       | 
       | Most of them are built so the front doesn't fall off at all.
        
       | alkonaut wrote:
       | Lucky it didn't happen half way. Could have been several hours on
       | one engine and the other one shaking and on fire.
        
         | [deleted]
        
         | xxpor wrote:
         | Luckily flight plans are always required to be within a certain
         | number of minutes of a place to land, and are certified to
         | operate on one engine for that period.
         | 
         | https://en.m.wikipedia.org/wiki/ETOPS
        
           | azalemeth wrote:
           | Very rudely, I'd like to mention the popular backronymn for
           | ETOPS: "engines turn or passengers swim"...
        
           | yread wrote:
           | ETOPS helps but it assumes that the engine is just shut down.
           | Here you have compromised aerodynamics and potentially the
           | wing, tail or other systems damaged by the parts of engine
        
             | xxpor wrote:
             | Of course. But simply an engine not working shouldn't be a
             | concern. Obviously land as soon as possible, but it's not
             | really that dangerous (assuming the other engine doesn't
             | fail for the same reason)
             | 
             | Turbine blades failing and piecing a hydraulic line on the
             | other hand...
        
           | midasuni wrote:
           | 138 is a certain number of minutes. It's still a long time.
        
           | [deleted]
        
           | alkonaut wrote:
           | Indeed. The scary part here isn't the loss of (function in)
           | one engine, it's structural issues, fire and so on. A violent
           | engine failure can give a whole range of problems beyond just
           | the loss of the engine. It would likely have been ok even
           | half way to Hawaii, but it would have been scary.
        
           | WalterBright wrote:
           | The shaking would concern me.
        
           | mrfusion wrote:
           | How do you account for oceans?
        
             | disantlor wrote:
             | i think in part by having more than 2 engines on those
             | flights
        
               | Pasorrijer wrote:
               | Very few in service aircraft in commercial passenger
               | fleets have more than two engines, and even the ones with
               | more than two engines have modified ETOPS rules to comply
               | with.
        
               | midasuni wrote:
               | The two that come to mind are the 747 and a380
        
             | jrockway wrote:
             | By having airports on islands, or by pushing up the number
             | of minutes that the engines/operator are certified for.
        
               | ufo wrote:
               | For transatlantic flights, two important "backups" are in
               | Iceland and in the Azores. I wonder how often airplanes
               | actually have to detour to these airports...
        
               | kps wrote:
               | Last I know of is
               | https://en.wikipedia.org/wiki/Air_Transat_Flight_236
               | running out of fuel.
        
               | sxcurry wrote:
               | Years ago I was on a 747 from SFO to LHR that landed in
               | Iceland - oil pressure problem in an engine. A guy drove
               | out with a pickup truck, climbed into the engine using a
               | ladder in the back of the truck, and started hammering
               | away. After a few hours in the terminal we got back on
               | the plane and flew the rest of the way to LHR. I kept
               | wondering just how qualified he was...
        
               | will_asouka wrote:
               | Happens fairly regularly but for passenger issues rather
               | than technical- medical emergencies and disruptive
               | passengers usually.
               | 
               | Airlines have contracts with companies who provide a sat
               | phone link to doctors who have the flight information and
               | medical facilities at possible diversion airfields. Eg
               | MedAire.
        
               | jfk13 wrote:
               | It happens: I was on an London - USA flight that detoured
               | to Iceland some years ago. (Fortunately nothing was
               | seriously broken, burning, etc., but there was a warning
               | indication of some kind that the pilot wanted to have
               | checked.)
               | 
               | The view coming in to Keflavik, with whales swimming in
               | the ocean below, was pretty cool.
        
               | snuxoll wrote:
               | Note that ETOPS goes beyond just engine ratings, it also
               | requires the operator meet all sorts of additional
               | requirements (what if you DO have to divert - can you
               | have the passengers retrieved within 24 hours, do you
               | have food and shelter if you have to divert to a non-
               | commercial airport along the flight path, are your
               | technicians doing proper maintenance, etc).
        
               | jrockway wrote:
               | Good point. Edited my comment to add that :)
        
             | Tuxer wrote:
             | Transoceanic aircraft need lots of ETOPS time. For example
             | the boeing 777 (twin-engine, transoceanic) has an ETOPS of
             | 330 minutes, so it always needs to be 330 min away from an
             | airport (which is 11 hours of flight from airport A to
             | airport B, not taking wind into account)
        
             | DeepYogurt wrote:
             | ETOPS accounts for oceans. Please read the link.
        
             | ghaff wrote:
             | The "certain number of minutes" includes being over oceans.
             | If you're too many minutes, you can't fly there. ("Minutes"
             | are fairly large. I believe at least one Airbus aircraft is
             | now at 4 hours.)
        
             | tshaddox wrote:
             | Generally transatlantic jetliners have more than 2 engines,
             | although I suppose that's beginning to change.
        
               | NikolaeVarius wrote:
               | This has not been true for a decade
        
               | rsynnott wrote:
               | The vast majority of transatlantic airliners today are
               | two engine aircraft. For four engines, you're basically
               | looking at 747s and maybe the odd a340 that has somehow
               | escaped retirement. The last large four engine airliner
               | will go out of production next year.
        
               | ghaff wrote:
               | That really hasn't been true since 747s started to be
               | retired so it started to change years ago and 2-engine is
               | now essentially the norm.
        
             | alistairSH wrote:
             | By staying as close to land as required to ensure safety.
             | until fairly recently, flights to Hawaii were largely
             | served by 3- or 4-engine jets. It's only in the last
             | several decades that ETOPS regulations have shifted enough
             | to allow regular twin-engine service to Honolulu.
             | 
             | See the 3rd response...
             | https://www.airliners.net/forum/viewtopic.php?t=119921
        
               | Aperocky wrote:
               | The regulations have been shifted but only time will tell
               | if it should be shifted. I guess we'll find out in 20
               | years.
        
             | bonestamp2 wrote:
             | You stay close to land as much as possible. For example, LA
             | to Tokyo, you basically fly up the west coast, give
             | Canada's west coast a high five, and then come around below
             | Alaska. It's less direct than it could be, but it's much
             | safer in the event of an emergency.
        
               | bluGill wrote:
               | It is more.direct than it sounds though because the earth
               | is round and so the shortest distance between two points
               | curves.
        
       | userbinator wrote:
       | This has happened twice before to Southwest too:
       | 
       | https://en.wikipedia.org/wiki/Southwest_Airlines_Flight_3472
       | 
       | https://en.wikipedia.org/wiki/Southwest_Airlines_Flight_1380
        
       | trimbo wrote:
       | VASAviation already has the radar/ATC video up:
       | https://www.youtube.com/watch?v=G7-zh7Sebr8
        
       | dmoy wrote:
       | That quoted ground observer. Do they work for the NTSB or
       | something?
       | 
       | I am 110% certain that if I saw a plane on fire in the sky, I
       | would not have the presence of mind to remember the term "cloud
       | deck", let alone the rest of those details.
       | 
       | Ground observer: "Good sir, I do say that the cloud deck was
       | quite low so I didn't get a good look, but the engine was mildly
       | louder than usual, and possibly had smoke, but perhaps not, and
       | appeared to be under control the whole time."
       | 
       | Me, probably: "AAAAAAAAAAAAA PLANE ON FIRE IN THE SKY, RUN!!!"
        
         | azalemeth wrote:
         | It's very likely that they're an AvHerald reader. It's the
         | absolute de facto gold standard website in its field, and
         | sensationalism and drama is not appreciated -- a large chunk of
         | the usual audience are aviation professionals. My dad was a
         | pilot, and I've got some few hours myself. You can bet that if
         | either of us watched this event happen, we'd mentally be
         | documenting it as best as we possibly can, both to try to
         | predict any useful information (e.g should we try to move!),
         | and for any subsequent investigation.
         | 
         | The excellent safety record of aviation originates from a
         | detailed and pedantic paper trail that is written in blood.
         | It's by learning as much as possible from every incident,
         | without fear of censure or blame, that makes the skies safer
         | for everybody.
        
           | lrossi wrote:
           | I can draw some parallels between that and a healthy SRE
           | culture. Except for the casualties, of course. Wondering if
           | the first SREs who created the guidelines had aviation
           | industry experience.
        
             | jeffrallen wrote:
             | Brent Chapman was one, and he worked in volunteer search
             | and rescue.
        
             | kwertyoowiyop wrote:
             | Aviation regulations are written in blood. SRE regulations
             | are written in lost weekends.
        
               | Xylakant wrote:
               | Depends on what systems the SRE is managing or even on
               | the downstream clients relying on their work. Around Y2K
               | a bug took the out the emergency call application for the
               | fire department in Berlin at midnight New Year's Eve.
               | People died because dispatch was not available. It's an
               | IT system where people die if you mess up. AFAIR in one
               | of the earlier prolonged AWS outages, some sort of
               | medical provider failed and people were at risk. It's not
               | all just display ads on websites.
        
             | dzhiurgis wrote:
             | low key feel opposite - chaos engineering (to an extent
             | obvs) would benefit flight controls...
             | 
             | it's like that old experiment that i cant find source for -
             | wall st traders switched with military guys and wall st
             | outperformed mils because they are used to dealing with
             | uncertain information...
        
           | bananasbandanas wrote:
           | There is a now a comment on that article where the ground
           | observer identifies himself and gives a few more details, so
           | looks like you're right.
           | 
           | > _1) I was giving Simon a heads up to look for a report out
           | of DEN - if it was anything, I thought it was just something
           | like a (big) compressor stall. That was why so many caveats
           | were there - I wasn 't sure at the time that the aircraft had
           | had a problem. I didn't realize it was going to be widely
           | reported until my mother texted me a couple of hours later
           | asking if any of the plane parts came down close to me_
           | 
           | > _2) Something I omitted that I should have put in: After I
           | got home I imagined how many thumb-widths at arm 's length it
           | would take to occlude it (from memory), and plugged that into
           | similar triangles and the length of a 737 (didn't realize it
           | was a 777) to get an estimated altitude and got 2-4 thousand
           | meters. I thought the cloud deck was only 2000 feet AGL or
           | so, so I didn't believe the numbers. I did change "a couple"
           | to "a few" though. Turns out it was ~8000 feet AGL. I should
           | have believed more in the math!_
        
           | billfruit wrote:
           | Only looked up Aviation Herald after you mentioned. Very
           | informative, almost HN like, but even more dense and topical.
        
           | kortilla wrote:
           | > aviation originates from a detailed and pedantic paper
           | trail that is written in blood
           | 
           | The saying is "aviation regulations are written in blood"
           | because each new regulation is usually in response to crash.
           | https://aviation.stackexchange.com/questions/13081/why-do-
           | pe...
           | 
           | You don't keep a "paper trail written in blood".
        
         | sn41 wrote:
         | Pretty sure he was a pilot or a sea captain. I definitely would
         | not refer to the right hand engine as "starboard engine".
        
           | [deleted]
        
         | perl4ever wrote:
         | >"AAAAAAAAAAAAA PLANE ON FIRE IN THE SKY, RUN!!!"
         | 
         | I grew up about 5 miles from an airport and for many years I
         | had a recurring dream that I was looking out the window at an
         | airliner that looked odd somehow or other, until I realized
         | with growing horror it was going to crash in the back yard.
         | 
         | I never saw anything like it in real life, nor was it ever a
         | concern for me whether I was in a flight path when deciding
         | where to live, but evidently my subconscious had a "to do" list
         | that included "be prepared for planes dropping out of the sky".
         | 
         | Strangely, I didn't have nightmares ever that I can remember
         | about being _on_ a plane in distress. Even though as I got
         | older I got more anxious about flying.
        
           | maweki wrote:
           | The first Final Destination movie starts with a ground
           | observer scene of about that distance of a plane crashing
           | right after takeoff.
           | 
           | I don't know whether your age fits, but maybe you saw this
           | and recalled it in your sleep every so often.
        
             | cko wrote:
             | I have the same recurring dream a few times a year. I
             | believe for me they started after 9/11.
             | 
             | Add that to the recurring dreams of losing all teeth, going
             | to school only to realize there's a 20 page essay due,
             | dinosaur attacks (inspired by Jurassic Park), and barely
             | missing my school bus (that was just this morning).
             | 
             | Btw I'm 35 now.
        
               | russum wrote:
               | Ugh, that "loosing all teeth" dream is very disturbing,
               | quite annoying and even painful! Good thing is that I
               | usually don't get it unless I had quite a few drinks the
               | night before.
        
         | avh02 wrote:
         | I recently listened to one of the radio correspondents (Herbert
         | Morrison) [1] that was observing the hindenberg coming in - and
         | it amazed me the things he thinks of while he's talking about
         | it (how the people waiting for the passengers will be
         | distressed) and the eloquent language used. ("Oh, the
         | humanity!")
         | 
         | That said, he definitely also got distressed, but mostly
         | remembered to describe.
         | 
         | [1] https://www.youtube.com/watch?v=DJ2qP4wd4LE
        
         | willyt wrote:
         | I expect the person interviewed is a pilot?
        
           | dboreham wrote:
           | Or an engineer?
        
         | throwanem wrote:
         | You'd be surprised. Years back, I saw what looked to be a near
         | midair collision, including a smoke trail from one of the
         | involved aircraft, and watched for a while from the front right
         | seat of the Jeep my boss was driving us to a job site in.
         | Presence of mind isn't really an issue. You're more just trying
         | to understand and follow what you're seeing.
         | 
         | Today, of course, I'd be watching through my 500mm lens and
         | taking pictures all the while. This was long before I got back
         | into photography, though, and long before you could get a 500mm
         | tele that didn't cost as much as a car. Even so, it was
         | interesting, not frightening - remember that the sky is a long
         | way away, and so are most things that happen there, weather
         | notwithstanding.
         | 
         | Never did find out what actually happened.
        
           | [deleted]
        
         | karlkatzke wrote:
         | No offense towards the average bear, but I would probably have
         | dictated a statement the same way.
         | 
         | I'm not an average bear though. I regularly read and refer to
         | things learned from airlines and other high criticality career
         | fields, and talk about them at conferences. My sister is an
         | airline pilot and I might have been if I wasn't medically
         | disqualified.
         | 
         | I do participate in government emergency response work and that
         | looks like the type of statement that would come from a trained
         | observer who knows how to express directionality as
         | unambiguously as possible.
        
       | moltenguardian wrote:
       | Probably a dumb question, but why don't the pilots cut the fuel
       | to the right engine after they know it's on fire?
        
         | PaulAnunda wrote:
         | Someone in the comments mentioned that that isn't a fuel fire;
         | its materials in the engine that are burning.
        
         | l31g wrote:
         | What is burning is probably leftover oil.
        
           | jacquesm wrote:
           | Fanned by a couple of 100 mile/hour winds. It would take a
           | small miracle for the fire to go out by itself under those
           | conditions, they may have tried to flood it with CO2 but it's
           | so open to the elements even that may no longer work.
        
         | elteto wrote:
         | I'm almost certain they did. You might be seen the runoff in
         | the lines?
        
         | quiescant_dodo wrote:
         | There are long checklists for handling uncommon scenarios like
         | this. I would expect that was one of many items on the list,
         | but I'm not familiar with the checklists. It is possible that
         | the explosion disabled the fuel controls.
        
         | gecko wrote:
         | They do, but there may be residual gas or punctures that cause
         | a gas leak. That's why each side of the plane has its own fuel
         | tanks as well.
        
       | GekkePrutser wrote:
       | That's crazy, in the Netherlands today there was another flight
       | that dropped engine parts (much smaller though, they're said to
       | have been turbine blades) that hit cars and people. It was also
       | an airliner (747-400).
       | 
       | Considering how rare an occurrence is, it's really weird to have
       | both happen on the exact same day.
       | 
       | https://www.airlive.net/breaking-turbine-blades-of-a-boeing-...
       | 
       | By the way I'm surprised that fire keeps going on the B772. I
       | assume the fuel was cut off, especially as the turbine seems to
       | be just spinning in the wind. I'd imagine the remaining fuel
       | would burn off quickly?
       | 
       | This would really be scary being a passenger (especially when you
       | know the wing it's hanging under is full of fuel).
        
         | almost_usual wrote:
         | Poisson distribution, higher probability of short periods
         | between failures than long ones.
        
           | dmos62 wrote:
           | Anyone care to elaborate? I don't understand what he means,
           | but I feel like this is an interesting thread to pull.
        
             | nl wrote:
             | Briefly: if you expect 10 failures in 10 years evenly
             | distributed then you would expect 1 per year.
             | 
             | If it is a Possion distribution then you'd expect them to
             | bunch up and get years with none, then them concentrated
             | over a few years.
             | 
             | Possion distributions usually imply a time factor. That's
             | concerning in this case as it implies maintenance isn't
             | effective.
        
               | nyolfen wrote:
               | how would this apply to disparate aircraft on different
               | maintenance cycles?
        
               | gamegoblin wrote:
               | It has nothing to do with aircraft, and everything to do
               | with random chance. Basically, it is _more likely_ for
               | time-series data to have clumps than to be perfectly
               | even.
               | 
               | Imagine you throw a three darts a board. Which is more
               | likely: all darts are equidistant, or 2 of the darts are
               | closer to each other than the 3rd? Now imagine it's 3
               | events in time rather than 3 darts on a board. And the
               | same logic applies to an arbitrary number of events, of
               | course.
        
               | nyolfen wrote:
               | it seems to me that there is a lot of room between
               | "perfectly even" and "twice on the same day"
        
         | laurent92 wrote:
         | Random = clusters happen.
         | 
         | In fact, mathematicians were hired during the Battle of England
         | to estimate whether the Germans were aiming for specific
         | buildings ("why is there a cluster of bombs around this
         | church???" or around some secret offices) or just spreading
         | randomly. Verdict: They weren't aiming, it was random chance
         | that bombs made some clusters onto some buildings. This is what
         | random looks like: No even distribution, sometimes you get a
         | cluster which looks like a series.
        
           | Stupulous wrote:
           | I think it depends on how frequent the thing in question is.
           | If an engine losing parts is something that happens yearly,
           | twice in one day is still pretty rare.
           | 
           | But then you have to deal with degrees of freedom as well. If
           | your search space is just 'two uncorrelated ~yearly events',
           | there's enough of them that you'll always find false
           | positives.
        
             | davrosthedalek wrote:
             | For independent, random occurrences, the probability
             | distribution for delta-T follows an exponential decay. I.e.
             | the most likely time is "right after". Of course, that
             | "most likely" can still be small. Fun fact: This is true
             | for _any chosen point in time_ , i.e. the prob that this
             | happens exactly one day after your birthday is higher than
             | that it happens two days later.
        
           | [deleted]
        
           | silvestrov wrote:
           | I've tried to find a non-clustering pseudo-random function.
           | 
           | Anybody knows the name or urls of those?
        
             | mathgenius wrote:
             | Maybe quasi-random is what you are looking for?
             | 
             | https://www.gnu.org/software/gsl/doc/html/qrng.html
        
               | silvestrov wrote:
               | This is exactly it! Many thanks for the name.
        
               | FabHK wrote:
               | There's the (descriptively named) "low-discrepancy
               | sequence", the most famous one being the Sobol sequence.
               | 
               | https://en.wikipedia.org/wiki/Low-discrepancy_sequence
        
             | MauranKilom wrote:
             | This is my go-to:
             | http://extremelearning.com.au/unreasonable-effectiveness-
             | of-...
        
           | aero-glide2 wrote:
           | Where I have read this before, Gravity's Rainbow?
        
             | pvitz wrote:
             | Grinstead & Snell in the part on Poisson distributions
             | maybe?
        
         | yread wrote:
         | It could be oil that's on fire
        
         | rossdavidh wrote:
         | There is a saying, something like "once is bad luck, twice is a
         | coincidence, three times is enemy action". So, if you get more
         | than two big planes crashing in the same day, it's likely
         | something like Al Qaeda (sp?) on 2001/09/11. If it's two
         | planes, it's likely bad luck.
        
         | ddalex wrote:
         | https://en.wikipedia.org/wiki/Clustering_illusion
        
           | foepys wrote:
           | I read on the German news about the Dutch incident and came
           | to HN because I knew that somebody would've posted about it
           | here. Found this thread and didn't fully read the headline,
           | just "Boeing" and "engine failure". It took me a few seconds
           | to realize that this was a completely different incident.
        
             | t0mas88 wrote:
             | The Dutch incident is a relatively common one, the reason
             | it's in the news is that turbine blades fell down on a
             | residential area and someone got minor burns from picking
             | one up.
             | 
             | It's more typical to have this kind of failure early in the
             | take off where the parts would fall on the airport and
             | nobody would talk about it.
             | 
             | All the rest of the news about circling at 10,000ft and
             | then landing at a nearby airport is completely standard
             | procedure that gets practiced all the time in the 6 months
             | simulator checks. Basically you climb high enough to be
             | able to dump fuel without it reaching the ground (minimum
             | 6000ft, preferably higher) and still not too high such that
             | you're burning a lot of fuel quickly because at 10,000 ft
             | fuel usage is way higher than at 30,000. Then when the fuel
             | dump is complete, engine secured, checklists done it's a
             | relatively normal landing. Especially if you have 4 engines
             | but even with 2 it's a landing every pilot can do and is
             | trained for all the time.
        
       | baptistejamin wrote:
       | I don't really understand why this information is now #1 on
       | HackerNews.
       | 
       | Boeing 777 engines are the world's largest turbofans and pw4000
       | Engine, involved in this explosion is in production since the
       | 80/90, and is already used on other Airframes like a330.
       | 
       | I know this accident looks impressive, but engine explosions like
       | this one are things that happens years over years.
       | 
       | On Airbus a380, similar explosions occurred.
       | 
       | This kind of explosions looks very impressive, but those are
       | things that happens quite a lot in aviation Industry.
        
         | fit2rule wrote:
         | >I don't really understand why this information is now #1 on
         | HackerNews.
         | 
         | Because HN readers invest, and this could have given some of
         | them time to short Delta/Boeing stock ..
        
       | [deleted]
        
       | beervirus wrote:
       | It's amazing that an aircraft can still fly pretty much normally
       | and land safely after such a failure. Imagine if software were
       | built with such resiliency.
        
         | pintxo wrote:
         | It exists, in the on-board systems of these planes.
        
           | beervirus wrote:
           | _737 MAX has entered the chat_
        
             | pintxo wrote:
             | How do you fix a broken hardware sensor in Software?
             | 
             | Wasn't that the initial problem?
        
               | beervirus wrote:
               | You write the software to detect and be resilient in the
               | face of hardware failure.
        
               | pintxo wrote:
               | If there is only one sensor, how do you know it's
               | reporting wrong data?
        
       | cbsks wrote:
       | Here's a good video of the flight path and radio communications
       | with the tower: https://youtu.be/G7-zh7Sebr8
       | 
       | It's always amazing too me how calm everyone seems in emergency
       | situations like that. It almost seems like a routine flight.
        
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