[HN Gopher] Starship's Third Flight Test [video]
___________________________________________________________________
Starship's Third Flight Test [video]
Author : BenoitP
Score : 439 points
Date : 2024-03-14 11:37 UTC (11 hours ago)
(HTM) web link (www.spacex.com)
(TXT) w3m dump (www.spacex.com)
| BenoitP wrote:
| When: 8:25 AM CT
|
| Launch window: 7:00 AM CT - 8:50 AM CT
|
| --- Updates:
|
| (future)T+40: Starship relight and entry
|
| T+12: Elevator music engaged, please stay tuned for T+40
|
| T+11: Payload door testing
|
| T+8: Upper stage SECO, nominal orbit insertion
|
| T+7: (mine) KSP moment for booster reentry, instabilities. Signal
| cut off because of exhaust conducts electricity and absorbs RF.
| Status unknown
|
| T-11: Still no blockers. Watching winds, may have hold at T-40s.
|
| T-30: Broadcast started
|
| T-60: (SpaceX Twitter) The Starship team is go for prop load but
| keeping an eye on winds, now targeting 8:25 a.m. CT for liftoff
|
| T-65: (SpaceX Twitter) Shifting T-0 a few more minutes to give
| boats time to clear the keep out area, now targeting 8:10 a.m. CT
|
| T-65: (SpaceX Twitter) New liftoff time is 8:02 a.m. CT, team is
| clearing a few boats from the keep out area in the Gulf of Mexico
|
| T-45: No blockers
|
| T-90: (SpaceX Twitter) Weather is 70% favorable for today's third
| integrated flight test of Starship. The live webcast will begin
| ~30 minutes before liftoff
|
| ---- Streams:
|
| High Quality VLC: Open VLC, Media, Open Network Stream, paste
| following, Play:
|
| (higher quality) https://prod-ec-us-
| west-2.video.pscp.tv/Transcoding/v1/hls/g...
|
| (lower latency) https://prod-ec-us-
| west-2.video.pscp.tv/Transcoding/v1/hls/g...
|
| NASASpaceflight: https://www.youtube.com/watch?v=RrxCYzixV3s
|
| Spaceflight Now: https://www.youtube.com/watch?v=EfnkZFtHPmM
|
| Everyday Astronaut: https://www.youtube.com/watch?v=ixZpBOxMopc
|
| LabPadre Space: https://www.youtube.com/watch?v=LMyXho_YCK8
|
| (FR) Techniques Spatiales:
| https://www.youtube.com/watch?v=BRXfWLVMEQ8
|
| ---- Mission profile:
|
| https://www.spacex.com/launches/mission/?missionId=starship-...
|
| ---- Links:
|
| https://twitter.com/SpaceX
|
| https://twitter.com/elonmusk
|
| https://old.reddit.com/r/spacex/comments/1bb8scf/rspacex_int...
| deadlydose wrote:
| Pretty sure the first YouTube link you provided is some scammy
| fake stream.
| BenoitP wrote:
| Updated, Thanks!
| BryanLegend wrote:
| Thanks, I like the Spaceflight Now commentary the most. Best
| analysis.
| ta1243 wrote:
| I find those youtube channels far too grifty for my tastes.
| Sadly as twitter doesn't seem to work ("Something went wrong.
| Try reloading.") I have lost quite a lot of the excitement I
| used to have for spacex.
| bryanlarsen wrote:
| I've been listening to SFN for about 20 minutes now and
| haven't heard a single reference to donations. Like parent,
| they're my preferred feed.
|
| If you can get SpaceX's twitter to work, you can use them
| for audio. If so, EverydayAstronaut will likely have the
| best video.
| SEJeff wrote:
| What's grifty about nasa space flight? They're a private
| news org that does incredible coverage of SpaceX and spends
| funds doing as such. They're mostly donation driven but
| they don't solicit them really. They just thank folks that
| do on their livestream. Their forums are an absolute
| goldmine of knowledge if you take a look and it is an
| incredibly friendly community.
| ta1243 wrote:
| Whenever I've seen them (not sure which specific ones)
| they've been either
|
| 1) Whining about donations (and shoutouts every few
| seconds)
|
| 2) Whining about the cost of cameras (I remember one of
| the early exploding and the commentator spent the next 10
| minutes going on about his expensive cameras)
|
| Yes they are funded by begging, that's not something I'm
| interested in listening too. I've seen US TV
| occasionally, I find it unwatchable with the jarring
| commercials, but I guess if you are used to that then the
| begging streams.
|
| The spacex stream traditionally is a good feed, not too
| fanboyish, no begging, but it seems it's no longer
| reliably broadcast
| cubefox wrote:
| The official SpaceX hosts often don't mention when
| something goes wrong or looks bad. For example, they
| didn't comment on the ongoing tumbling of the ship. Of
| course they want to present themselves in the best
| possible light. Other streamers are more independent,
| they do point out those things.
| sneak wrote:
| Well, first off, they're not NASA (or the NSF). I always
| thought it was sketchy that they used the name, it seems
| to imply that they are official when they are not.
| tompark wrote:
| i get the same message, but if you log into twitter then it
| says the stream will begin at 5:52am PDT
| numpad0 wrote:
| It's SpaceX's problem that they're not where the public
| expect them to be.
| namaria wrote:
| VLC stream links hit the spot for me... I was really hoping to
| see the official stream but twitter is... well... not what it
| used to be. Anyway thanks!
| _Microft wrote:
| The URL on the ,,VLC"-links look a lot like ,,Periscope"
| which was acquired by Twitter long ago. Maybe this is
| actually the official Twitter stream itself?
| namaria wrote:
| Whatever the infrastructure spacex is using for the stream,
| the twitter front end doesn't load for me. That's what I
| meant.
|
| edit: now it loads but it has 10s delay so I'm sticking to
| VLC
| greedo wrote:
| You can watch the stream directly from the spacex.com
| website.
| namaria wrote:
| Now this one isn't loading on my side. And I got gigabit
| fiber at a major European city close to a big exchange.
| 4ggr0 wrote:
| That's just the embedded twitter stream :D
| BenoitP wrote:
| It is, how to reproduce:
|
| Twitter stream page, F12, network tab, look for m3u8 file,
| right click, copy url, open in VLC
| chasd00 wrote:
| The nasaspaceflight streams are pretty good too. I like their
| commentary.
|
| https://www.youtube.com/live/RrxCYzixV3s?si=1MFBk8yzD3VcRdWk
| xixixao wrote:
| Going for fueling, launch scheduled with 25min left in the window
| (getting tight) (8:35CT). Watching wind speed.
| namaria wrote:
| I was just watching Spacex official stream and at ignition they
| switched to Musk hawking cryptocurrency. What just happened??
|
| edit: wild I just realized take off is 50 minutes from now...
| what had I been watching?? they did a countdown and there was
| ignition... was that a time wrap? Am I going insane?
|
| edit2: @spacex034 is not @spacex... today I learned...
| cam72cam wrote:
| SpaceX does not stream on YouTube, you are watching an old
| launch on a fake channel. Please report them.
| namaria wrote:
| Dang I got got. Thanks for letting me know
| bluescrn wrote:
| You weren't the only one, I clicked on it too, as did
| thousands of others, before finding a real stream
| sneak wrote:
| YouTube does a bad job of real time takedowns of spoofed
| live streams. You'd think for big events like this they
| would have somebody just standing by and monitoring
| social stuff so that things like this don't happen.
|
| Then again you'd think one of Amazon's 1.5M employees
| would have the job of finding fake USB sticks for sale on
| the site, but apparently nobody has that title either.
| dylan604 wrote:
| > You'd think for big events like this they would have
| somebody just standing by
|
| This implies that YT has humans that are not in sales. It
| feels like YT just has bots building more bots at this
| point.
| dpcx wrote:
| Is that new? Because SpaceX has streamed launches on YouTube
| for years.
| TOMDM wrote:
| Yes, the official stream is only on Twitter now.
| greedo wrote:
| They also stream the launch live on the spacex.com
| website.
| ta1243 wrote:
| Thank you
|
| I tried signing up for twitter but gave up at the "match
| these dice with these symbols (1 of 10)" stage.
|
| It's not a great interface compared with youtube etc, not
| rewinding etc, but at least it works
| sneak wrote:
| That's a Twitter embed on the SpaceX website. It's still
| streaming from Twitter.
| dylan604 wrote:
| but no Twit...er, X account required
| namaria wrote:
| I will be deep in the cold cold ground before I recognize
| Twitter's new name
| dylan604 wrote:
| you see how I refer to it. it gets both names in there,
| and expresses the disdain and the confusion all in one
| go.
| pixl97 wrote:
| They did that for IFT-2 and the first channel I went to was
| one of those crypto bullshit things too. Very dumb decision
| on SpaceX's (well probably Musk himself) part.
| Hamuko wrote:
| Musk decided that Twitter is now a video platform and he's
| decided to dogfeed with SpaceX.
| atonse wrote:
| Twitter was a video platform before Musk took over. They
| were doing Thursday night football (NFL) and other
| things.
|
| Looking at the SpaceX feed, they seem to be using
| whatever tech they got from the Periscope acquisition (at
| least the servers were still pscp.tv).
| Hamuko wrote:
| Twitter was not a video platform - it had (some) video
| features. Very different. And people always considered
| Twitter videos to absolutely suck.
| hnbad wrote:
| That hasn't really changed though. He's just decided to
| manifest "Twitter is a video platform" into existence.
| The controls are still total ass though.
| mavhc wrote:
| you were not watching the Spacex official stream?
| jfoster wrote:
| There's a fake SpaceX YouTube account that looks official
| because they included videos from the real channel in playlists
| to get verification ticks & have managed to harvest thousands
| of subscribers. YT's interface is a bit dumb for including the
| verification ticks in that use-case.
| smallmancontrov wrote:
| YT's interface fights negative feedback harder than a spoiled
| toddler.
|
| Hiding downvotes, squirreling the "block channel" feature
| into a dot menu, breaking it completely on recommended pages,
| and then breaking search pages... it's almost like they don't
| want to fight spam.
| sph wrote:
| They're in the ads business - watched hours = money.
|
| Why remove spam and clickbait when it means less money?
| Youtube is the stereotype of post-hype company that is just
| milking its users to increase their bottom line, driving
| the entire product to a slow death.
| dylan604 wrote:
| They get paid to serve that spam. Why would they reduce the
| avenues to serve the spam?
| trollied wrote:
| > looks official because they included videos from the real
| channel in playlists to get verification ticks
|
| That is not how it happens. The account is verified because
| it is a stolen account that had lots of subscribers & views.
| They hide/delete the existing videos & rebrand the channel.
| It famously happened to Linus Tech Tips last year after a
| staff member fell for a spear phishing attempt.
| sph wrote:
| You got bamboozled by an AI Elon deep fake.
| namaria wrote:
| Oh man and I had just downloaded the top result when
| searching app store for bitcoin wallet to send him bitcoin so
| he would double it for me!
| bbarnett wrote:
| Wait, double it? Would you please link me?
| fallingknife wrote:
| Screw that! I'll triple any BTC you send to this address:
| fjreisorhsksjshsjsjsj
| bbarnett wrote:
| I'm sorry sir, but my software won't take that address, a
| typo? Please resend.
| elif wrote:
| this is probably exactly why x started doing video. youtube is
| so full of fake channels that it readily presents fake ones at
| the top of search results.
|
| the x stream has been great and had a far greater reach (2.5
| million) than any of the youtube streams by a factor of 10x or
| so.
| ajross wrote:
| Twitter is awash with garbage too, likely even worse. Every
| major account, without exception, has multiple fake clones
| (often many created per day) running around trying to steal
| clicks and occasionally phish users. The Internet is just
| hard.
|
| You're just saying that the Twitter official account is
| official. No reason you can't have an Official Account
| anywhere else, SpaceX just doesn't.
| elif wrote:
| when you search spacex on x, you are presented the official
| account first.
|
| when i searched spacex on multiple youtube apps this
| morning, i couldn't even find the official spacex account
| after going through pages of menus.
| ajross wrote:
| Again, because _there is no_ official SpaceX feed on
| YouTube, they deleted it. Can you link to the channel you
| think you should be seeing?
|
| To be clear: if you search for "SpaceX" on Google, you
| get the corporate website as the first link and the
| Twitter account as the second. But YouTube has nothing to
| show you, by SpaceX's choice.
| ghufran_syed wrote:
| This is what shows up for me:
| https://www.youtube.com/spacex
| elif wrote:
| you are searching channels. that is not available on, the
| roku app, for instance.
|
| if you search by channels on x, for fair comparison,
| there are no spoofed spacex accounts to be seen anywhere.
| https://twitter.com/search?q=spacex&src=recent_search_cli
| ck&...
| russdill wrote:
| NSF had 1.5M views on their stream, Everyday Astronaut had
| 1.8M views.
| cchance wrote:
| ya theirs a shitload of fake spacex streams with AI generated
| crypto scams
| cruffle_duffle wrote:
| Dude, we encountered that yesterday. Somebody really figured
| out how to successfully pretend to be a spacex livestream! It
| was super weird, right?
| whitehexagon wrote:
| Anyone have a non youtube link please?
| mdorazio wrote:
| SpaceX does not stream on YouTube anymore. You can always get
| the official X broadcast link off their spacex.com launches
| page. Here's the one for today:
|
| https://www.spacex.com/launches/mission/?missionId=starship-...
| whitehexagon wrote:
| thanks, I had to unblock twitter.com on my firewall, lets see
| if it starts up [edit] up and running, great!
| SushiHippie wrote:
| FWIW, this seems to be the m3u8 link of that stream:
| https://prod-ec-us-
| west-2.video.pscp.tv/Transcoding/v1/hls/g...
| whitehexagon wrote:
| Wow, the re-entry is almost as exciting! hopefully the ship
| got the heat shield rotated into position again. I wonder why
| they dont cover the whole rocket with them if they are as
| light as they demonstrated. Amazing watch anyway, thanks.
| macintux wrote:
| Placing the heat tiles is (currently) entirely manual, and
| is very time-consuming. Starship is _big_.
| conradgodfrey wrote:
| For an uninformed person like myself - what's the expectation for
| this launch? Is it expected to explode like the last two?
| TOMDM wrote:
| They are hoping to achieve a hard landing in the ocean.
|
| Given the progress shown between the first and second
| integrated test, odds are decent that they'll achieve it,
| however they are also trying for a number of firsts in orbit so
| who knows.
| pixl97 wrote:
| Well, yes, but the question is when.
|
| If everything goes right the booster will likely explode when
| it lands in the gulf . Starship itself will most likely explode
| on reentry somewhere over the Indian ocean.
|
| Now, I think the question is, will it explode before then, and
| of course that's why they do flight tests to find out.
| pixl97 wrote:
| Replying to myself. Booster made the boost back burn
| successfully and had a mostly controlled flight into the
| gulf. I say mostly because it looked like it had some
| instability and met the water somewhere close to 1000km/h if
| telemetry was right (or went unstable just before then).
|
| 10 minutes into flight starship is coasting in space for the
| next 30 minutes and should relight at around 40 minutes.
| elif wrote:
| the instability was due to partial engine relight
| cwillu wrote:
| It looked to me like there was some major oscillations
| shortly before the engines relit though.
| pixl97 wrote:
| Yea. If I had to make an uneducated guess I'm thinking
| one of two things.
|
| 1. Starship is leaky. Outgassing and/or leaky valves made
| attitude control difficult and used up ullage gasses
| quickly.
|
| 2. Thrust control/RCS has programming or physical issues.
| Saw a lot of ice breaking off places near deorbit, so if
| you had ice building up and redirecting gas the ship
| wouldn't perform as the computer expects.
| allenrb wrote:
| Very excited for this as usual, and thanks to a few delays, I
| won't be on the train at T-0.
|
| As for expectations, I'll be thrilled to see Starship reach
| orbital velocity. Last time was so close. Engine restart and
| intact reentry? Even better but maybe more of a stretch? Fears?
| Only that it doesn't do as well as IFT-2. And that's always a
| possibility.
| boiler_up800 wrote:
| Also commuting around this :) Looks to be very successful. I
| wonder how many tests the ship can pass in orbit.
| duluca wrote:
| What an amazing effort. Best of luck to team SpaceX. I really
| hope both ships survive all the way to the ocean this time.
| piva00 wrote:
| It's flying! And all engines are burning, it's pretty damn
| impressive to see this thing lift off.
| perihelions wrote:
| It's in orbit!
|
| ( _"...and we have a callout for nominal orbit insertion... "_)
|
| edit: Not actually in orbit! This is a suborbital flight. Mea
| culpa
| preisschild wrote:
| Technically its suborbital
| thelittleone wrote:
| Isn't orbit above 125 miles (200km)?
| madaxe_again wrote:
| Orbit is when you drop an apple off a dining room table -
| it's just a very crappy orbit.
|
| "On orbit" typically means in a stable orbit around a body
| - but in the case of starship, it could have been on orbit,
| the delta v is more than sufficient, but that's an unsafe
| configuration if you don't know your engines will relight.
| apendleton wrote:
| Orbit is mostly about speed, not about height. Going
| straight up and down doesn't count, even if you pass the
| height that some orbital vehicles attain.
|
| This vehicle is actually going orbital speed, but not quite
| orbital height (or rather, it's in an "orbit" that has a
| very eccentric elliptical shape that would cause it to hit
| the atmosphere on its way back around; it'd be well above a
| typical orbital height at apogee, though).
| ta1243 wrote:
| Technically you can orbit the earth at a pretty low
| speed. Geostationary satellites orbit about 5,500kph,
| which is far slower than the 26,000kph starship reached
| today.
|
| You just need to get high enough, and be pointing in the
| right direction.
| KineticLensman wrote:
| Orbit is when you turn the engines off and stay up there.
| hoorayimhelping wrote:
| Space is generally defined to be 100km above earth's
| surface, an arbitrary point called the Karman Line [1].
|
| Orbit is when an object is traveling so fast that it
| reaches the horizon of a body before the body's gravity can
| pull it down to the surface, but perpetually. It's
| basically perpetually falling around the body. Imagine one
| of those guys in a wingsuit skimming along the surface of a
| mountain, never actually touching the surface. It's similar
| to that, but at a much higher scale.
|
| 1) https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line
| usrusr wrote:
| Orbit is a speed, not a distance. You could do a suborbital
| hop that has its highest point beyond the orbit of the
| moon. (if you aim very, very well)
| WithinReason wrote:
| At the same time, if your velocity vector is pointing
| towards the ground you're not achieving orbit no matter
| your speed
| the8472 wrote:
| It works if you're a black hole or a chunk of degenerate
| matter. For transatmospheric orbits being a large ball of
| iridium will work too.
| malfist wrote:
| It's in space (above the Karman line), but not in orbit.
| Orbit implies it has the velocity for staying in space,
| which isn't the intention here. If anything goes wrong they
| want to be able to not leave junk in orbit
| ghufran_syed wrote:
| It's at 26000 km/h which sufficient for orbital velocity. It
| looks like it's in an elliptical orbit. I guess we'll see
| soon if they need to do a de-orbit burn, or if the orbit just
| intersects the atmosphere and they use atmospheric braking?
| perihelions wrote:
| I did the math. So, the minimal orbit at 180 km, the one
| that grazes the earth's surface at its perigee, is about
| 7.75 km/s or 27,900 kph. The other commenters are right: it
| was never technically orbital.
|
| edit: (let* ((m 398600.0) ;; km^3/s^2
| (r 6371.0) ;; km (peri (+ r 0.0))
| (apo (+ r 180.0)) (a (* 0.5 (+ peri apo))))
| (sqrt (* m (- (/ 2.0 apo)
| (/ 1.0 a))))) ;; 7.745844595118488
| ghufran_syed wrote:
| Thanks! On one of the feeds, it sounds like they didn't
| want to leave a bunch of debris in orbit if they had an
| anomaly
| BenoitP wrote:
| > 26000 km/h
|
| > 27,900 kph
|
| Seems like they want to test the limit. Same speeds as
| LEO, but guaranteed to come down.
| grecy wrote:
| That is really cool. For those of us that are space nerds
| but don't have the depth of understanding, do you mind
| walking us through the calculation above?
| perihelions wrote:
| I apologize I don't have a good explanation of it at
| hand! It's a form of the vis-viva equation [0] that's
| basically a restatement of conservation of energy. It
| derives the (scalar) speed of an object in a 2-body
| orbit, at any position within that orbit, as a simple
| function of their separation distance.
|
| In the form I'm using, I'm using standard parameters of
| an elliptical orbit: the periapsis (the closest approach
| to the center of mass of the massive body (which is a
| focal point of the ellipse which the orbit traces)),
| apoapsis (farthest distance), and semimajor axis (their
| arithmetic mean [1]). I'm evaluating the orbital velocity
| at the highest point, the apoapsis. m is a short form for
| the product G*M, the standard gravitational parameter [2]
| of Earth (which is known to much higher precision than
| either the universal gravitational constant G, or the
| mass of the earth M, individually).
|
| The particular orbit I'm applying it to is one whose
| periapsis is equal to the Earth's radius--an orbit that
| touches the surface of the Earth. This is the dividing
| line for orbital / suborbital: a suborbital trajectory is
| one that (mathematically) goes beneath the Earth's
| surface.
|
| [0] https://en.wikipedia.org/wiki/Vis-
| viva_equation#Equation
|
| [1] https://en.wikipedia.org/wiki/Semi-major_and_semi-
| minor_axes...
|
| [2] https://en.wikipedia.org/wiki/Standard_gravitational_
| paramet...
| grecy wrote:
| No apology needed, thankyou very much!
| eagerpace wrote:
| But it would have been if they executed the burn in at a
| slightly different angle.
| dotnet00 wrote:
| Technically it's a transatmospheric orbit. That is, an orbit
| such that it'd stay up there if the atmosphere were not
| present. The difference between this and full orbit is just a
| few seconds longer burn, so it's a difference with little
| meaning in terms of proving out the ability to reach orbit.
| perihelions wrote:
| I don't believe that's the case--see the math in my sibling
| comment.
| dotnet00 wrote:
| The number going around from people who typically do this
| kind of thing is a ~55x235km orbit:
| https://twitter.com/planet4589/status/1768270310199935299
|
| I'm not really in a place to judge your math right now to
| really add anything on that.
| perihelions wrote:
| Yeah, that guy's absolutely a domain expert! But note
| that he writes -55 km, not +55 km--that is a suborbital
| trajectory. Its perigee is below the earth's surface; -55
| km is a negative altitude.
|
| (He's also clearly using a different set of data than I
| have access to. I can't read the context of the Twitter
| thread so I don't know what numbers he's looking at).
| dotnet00 wrote:
| Ooh that's a good catch, I subconsciously substituted the
| -55 for ~55!
| rawling wrote:
| Hahah, the elevator music while they wait for reentry...
| 4ggr0 wrote:
| I actually have the stream open in the background, can't
| believe how happy and calm this music makes me while patching
| servers :D
| engineer_22 wrote:
| Came here to say exactly this :) great choice of music!
| namaria wrote:
| If you like that here's a protip: search for bossa nova
| instrumentals on youtube for soothing tropical background
| music
| 4ggr0 wrote:
| Ahh, beautiful, thanks! :D
|
| Sounds like the perfect music to calm down in the evening
| or while cooking.
| euroderf wrote:
| or soma.fm secret agent radio (lots of bossa nova)
| corobo wrote:
| Music with intermittent control updates was great, reminded me
| lofi ATC exists (lofi music with airport control tower audio)
|
| https://www.lofiatc.com/
| geocrasher wrote:
| My first thought was "This sounds vaguely like the music on the
| radio in Portal. Does a future SpaceX become Aperture Science?
| Is Elon Musk the progeny of Cave Johnson?"
| dougmwne wrote:
| Starship has reached orbit!
| fernandotakai wrote:
| man, so much progress from the first two test launches.
| starship is alive and well, and the booster almost made it to
| soft water landing.
| simfoo wrote:
| 1000 km/h booster impact at sea, call that a "soft landing/splash
| down". Poor fishies :)
| _Microft wrote:
| I guess they didn't want to make it too easy for some Chinese
| fishing vessels ;)
| sneak wrote:
| Chinese fishing vessels in the Gulf of Mexico?
| schnitzelstoat wrote:
| They are on vacation.
| jajko wrote:
| On shores of Africa, in Gulf of Mexico... yes, in 2024
| ships can travel _far_
| bbarnett wrote:
| Probably even in Lake Superior.
| Kon-Peki wrote:
| I was going to write that a boat could get from the ocean
| into Lake Superior without ever entering the United
| States (by hugging the Canadian side of all lakes and
| rivers), but it appears that there is a dam on the St
| Lawrence River near Cornwall Ontario that forces you to
| take a short <10 mile detour through a river/canal in New
| York.
| Etheryte wrote:
| Illegal fishing by Chinese fleets is now commonplace in
| Africa, in Argentina, etc [0], so given how much they've
| expanded operations over the years it's only a matter of
| time before you see them there too, if it hasn't happened
| already.
|
| [0] https://www.nytimes.com/interactive/2022/09/26/world/as
| ia/ch...
| _Microft wrote:
| Some species are rare. You need to look in the right places
| if you want to catch some fine raptors.
| pixl97 wrote:
| Hopefully the NASA flight monitoring the launch has video of
| the booster coming back down.
| russdill wrote:
| The WB-57 was not in the air today.
| tempaway444641 wrote:
| It does look like it came down rather fast. Engines only
| partially re-lit. About 34min in this video
|
| https://www.youtube.com/watch?v=NWM1NQ1tZEU&t=2112s
| elihu wrote:
| I think that's the ascent burn. It doesn't look like the
| engines re-lit at all for the descent. (I imagine they aren't
| supposed to light until they're a lot closer to the ground
| than they were when the video was lost.)
| tempaway444641 wrote:
| At altitude 22km superheavy was moving at 4310 kmh (34:18
| in linked video) speed then dropped continually, at 34:45
| in the video the icons show that 3 engines were lit,
| altitude was 1km and speed was 1300 kmh. At 34:49 you can
| see flames, speed continues to drop, then you see the sea
| rushing up, then it cuts
| DarmokJalad1701 wrote:
| Beautiful flight so far!
| maxglute wrote:
| Breathtaking stream.
| hereme888 wrote:
| The elevator music during this next 30 minutes in orbit! lol
|
| Flawless launch.
| fabian2k wrote:
| Looked very impressive and there is enormous progress compared to
| the earlier tests. Especially as all engines seemed to work
| throughout the entire launch, the earlier tests had significant
| engine troubles so they seem to have a handle on that now.
|
| The reentry burn failing doesn't seem like a huge deal in this
| case, especially as the engines worked very well earlier.
| XorNot wrote:
| Its still an issue because they haven't really confidently
| demonstrated a relight of the engines while flying.
|
| Hot staging avoids a relight, but they still need to do it.
|
| It does mean they technically have an expendable heavy launch
| vehicle though.
| hughes wrote:
| The boostback burn demonstrated relight today.
| Daneel_ wrote:
| The key demonstration is "relight in a vacuum", which was
| the test that was skipped late in the stream. If you can do
| this then deorbiting is possible. Relight of the booster
| doesn't demonstrate this, unfortunately.
| hagbard_c wrote:
| > It does mean they technically have an expendable heavy
| launch vehicle though.
|
| That is how they started using Falcon 9 as well: first
| expendable but testing recovery - which failed several times
| in several interesting ways - until that process was refined
| into what now seems to be a normal thing: the first stage
| launches, drops off a second stage, turns around and makes
| its way back to either the launch site or a floating
| platform. I assume they have the same plans for this system:
| launch expendable while using the hardware to refine the
| process of recovery until in not that many years from now
| they launch and land and launch again.
| DarmokJalad1701 wrote:
| The test is essentially a success at this point. Starship can
| take payload to orbit and open/close the payload doors. The
| remaining things are icing on the cake. They can refine re-
| usability while flying payloads.
| enraged_camel wrote:
| I think they also successfully demoed in-space fuel transfer.
| xondono wrote:
| Fuel transfer with what? That would require things like
| docking
| Tor3 wrote:
| They transferred something like 10 tonnes of fuel from one
| end of the ship to the other.
| hagbard_c wrote:
| Transfer internally between tanks in the bottom and top of
| the ship. This was one of the planned tests, I have not
| heard whether it was accomplished though.
| dotnet00 wrote:
| There was a callout saying that it was successful.
|
| Edit: On the other hand tweets from Gwynne suggest that
| they still need to review the data to see if it was a
| success.
| enraged_camel wrote:
| They performed an in-ship fuel transfer, from one chamber
| to another. My understanding is that this is a very
| important pre-requisite for an actual transfer from one
| ship to another, because of the need to keep the fuel at
| cryogenic temperatures during the transfer, which is
| apparently not easy. Last time it was done was decades ago,
| but in kilograms. SpaceX just demoed a transfer of _tons_
| of fuel.
| extraduder_ire wrote:
| Bigger problem than keeping it cryogenic is getting it to
| one side of the tank while in orbit, so the pumps don't
| run "dry". Harder than just doing an ullage burn first
| too, because moving that amount of mass around also moves
| the vehicle.
| cchance wrote:
| They used tanks inside the ship to transfer from 1 to
| another to prove the process, was discussed and called out
| as success, and talked about many times before the flight
| ajross wrote:
| Not quite: the apogee burn they had planned didn't happen (no
| word as to why yet), so the ship didn't technically demonstrate
| the capability reach orbit. It came back down in the Indian
| ocean on its original suborbital trajectory, essentially like
| an ICBM.
| DarmokJalad1701 wrote:
| That is a matter of the trajectory they chose on purpose for
| this test flight. A different flight profile would have given
| them a perigee above the atmosphere (rather than -50 km)
| Laremere wrote:
| Parent's (correct) point is that it isn't a matter of the
| ascent trajectory. They can't leave the Starship up in
| orbit, and where it reenters needs to be controlled.
| DarmokJalad1701 wrote:
| > They can't leave the Starship up in orbit, and where it
| reenters needs to be controlled.
|
| Why? Plenty of boosters re-enter uncontrolled and burn up
| all the time.
| ajross wrote:
| Stated simply: zero-thrust "orbits" repeat the same
| trajectory again and again. So if you end your burn in
| the outer atmosphere near your launch pad, the next time
| around you will be _back_ in the outer atmosphere (near
| where the the launch pad "was", ignoring the rotation of
| the planet). And since there's air there providing
| resistance, you'll re-enter and crash.
|
| Getting to orbit requires at least one more burn near the
| apogee of the original orbit to circularize it and ensure
| the spacecraft doesn't approach the atmosphere again.
| Starship didn't do the apogee burn they intended to do,
| so didn't demonstrate this capability.
| DiggyJohnson wrote:
| Singe burn to orbit is pretty common though in reality,
| with the dynamics of staging, engine throttling, and
| precision insertion capabilities most modern rockets can
| hit the mark.
| DarmokJalad1701 wrote:
| > Getting to orbit requires at least one more burn near
| the apogee of the original orbit to circularize it and
| ensure the spacecraft doesn't approach the atmosphere
| again
|
| The Saturn V went direct to Earth orbit without requiring
| relighting the third stage engine.
| terramex wrote:
| Non-reusable boosters don't go into orbit and perform
| calculated crash into ocean soon after launch.
|
| Small second stages and spacecrafts can be allowed
| uncontrolled orbital reentries because they usually burn-
| up. Starship is too big for that, debris would rain like
| when Space Shuttle Columbia disintegrated over land. They
| most likely will need to show engine relight capability
| to control reentry point before going orbital.
| Toutouxc wrote:
| First thing that comes to mind: Starship has a lot of
| protection against burning up, so huge chunks of it could
| survive and cause damage.
| Laremere wrote:
| Afaik, when talking about objects large enough that some
| debris will actually hit the ground, only China
| intentionally lets their final stage re-enter
| uncontrolled. Everyone else at least has a plan for
| controlling re-entry. SpaceX has lost control of some of
| their Falcon 9 second stages before, but that's the
| exception not the rule.
| golol wrote:
| Ok so they could leave Starship in orbit and launch
| payloads like that. The idea however is to launch
| payloads WHILE testing reentry and landing. This requires
| an engine relight in orbit.
| DarmokJalad1701 wrote:
| > WHILE testing reentry and landing.
|
| > This requires an engine relight in orbit.
|
| The latter is part of the test at this point of
| development
| wolf550e wrote:
| Starship is huge and heavy and made of steel, it will not
| burn up on reentry, if it falls on a populated area it
| will kill people. They will not be allowed orbital
| trajectories until they demonstrate they can control the
| deorbit burn.
| dotancohen wrote:
| An empty Starship has a very low ballistic coefficient,
| it will be torn apart by the atmosphere if not carefully
| controlled. Add to that the FTS and there is no real
| danger to population on the ground.
| wolf550e wrote:
| Of course it will not maintain its shape, but the pieces
| that land will be large.
|
| It's made of 4mm thick steel sheets, and the FAA
| disagrees with you.
| mlyle wrote:
| Columbia was torn apart by the atmosphere... and dropped
| huge chunks that were a danger to people on the ground--
| some as large as a VW Beetle.
| dotnet00 wrote:
| Typically American policy is to have a controlled reentry
| option for as much as possible. The disposable first
| stages of all rockets don't need a controlled reentry
| because they are always suborbital and thus their
| splashdown location is relatively well known ahead of
| time. The second stages are typically supposed to deorbit
| and burn up over water after a launch to LEO. There are
| occasional cases where something goes wrong and they fail
| to deorbit, which is when we sometimes hear of the burn
| up due to gradual orbit decay being witnessed over land.
| travisgriggs wrote:
| I wouldn't classify the re-entry survival problem as icing. But
| otherwise, I agree with you.
| johnyzee wrote:
| Yeah, breaking up in-air during re-entry (at 65 km going by
| last telemetry) seems like a potential big issue to fix.
| tempaway444641 wrote:
| The point they were trying to make is that getting up is
| MVP, getting back down can be figured out later
| dotnet00 wrote:
| OP's point is that the tests become a bit cheaper and a bit
| easier to get licenses for since they can get to orbit and
| can deploy Starlinks. The reentry problems of course have
| to be fixed, but the FAA mishap investigation will involve
| fewer delays, just like how Falcon 9 was able to keep
| flying, attempting landings without having to wait for a
| mishap investigation to finish every time a landing failed.
| usrusr wrote:
| Iirc F9 had its main challenge in that final suicide
| burn. Usually the boosters made it there just fine and
| then "only" failed to get the parameters aligned just
| right.
|
| Based on what we saw today, the main chokepoint for
| Starship might be right in that hot reentry telemetry
| blind spot. Debugging without logs.
| dotnet00 wrote:
| It sounded like they might have had flight data recorders
| on-board which might have survived through reentry with
| telemetry. If so, they'd have some logs, but yes,
| figuring out reentry will likely be the main challenge
| for now, not only is it hard to debug, even getting to it
| requires everything else to go more or less perfectly.
| smallmancontrov wrote:
| With all the solid state gizmos we have today, is it
| really that difficult to make a blackbox that can survive
| serious impact G-forces, especially if it just needs to
| work and doesn't need to be safety rated?
| DarmokJalad1701 wrote:
| Unlike with F9, in this case they most probably had high-
| bandwidth telemetry all the way till the vehicle broke up
| (if the high-def video stream is anything to go by). So,
| they probably have a lot more data this time. Even the
| video can yield information - for example, given that the
| cameras were mounted on the flaps, they can probably back
| out the actuation angles from that.
| baq wrote:
| it's the expected outcome of an imperfect (literally not
| precisely perfect) reentry. something went wrong. it could
| be a very minor thing like a stuck valve somewhere. we'll
| know in the next test if they figured it out.
| DarmokJalad1701 wrote:
| > Yeah, breaking up in-air during re-entry (at 65 km going
| by last telemetry) seems like a potential big issue to fix.
|
| That's what pretty much every non-SpaceX rocket does today
| with very few exceptions.
| ta1243 wrote:
| And indeed every spacex rocket. Starship is the second
| stage -- and a second stage on a F9 burns up in the
| atmosphere just as much as Starship from IFT3 did.
|
| The big things to fix seem to be
|
| 1) The roll rates for starship (which prevented the
| inflight relighting test)
|
| 2) The Booster relights, which didn't have enough
| lighting to soft land.
|
| Both of those feel like minor problems.
|
| I'm amazed that the propellant transfer demo seems to
| have worked first time, and of course they managed to get
| the tihng up there in the first place.
|
| The reusability of the Starship part of the system is a
| much bigger unknown, but that doesn't seem to be
| necessary for the next launch.
|
| Wouldn't surprise me if the next try is by the end of
| April
| engineer_22 wrote:
| bright side: booster made it all the way to splashdown
| aeternum wrote:
| Why? Saturn V broke up in-air during re-entry on every
| "successful" launch as does every ULA rocket.
| johnyzee wrote:
| Because that is their stated design goal for Starship.
| DarmokJalad1701 wrote:
| And you don't need to meet that goal to start launching
| (risk-tolerant) payloads to orbit during their test
| flights. Especially with such a hardware-rich development
| program.
| wongarsu wrote:
| They have a great pipeline for building ships. They _want_
| reusability, but for near-term needs like deploying bigger
| Starlink satellites and their moon lander contract they could
| probably power through without reentry survival. It would be
| expensive, but unlike in-orbit refueling not really mission
| critical
| TMWNN wrote:
| My understanding is that Starship is financially comparable
| to Falcon 9 on a per-payload basis even if fully expended.
| cryptonector wrote:
| If so that would be amazing.
| dotancohen wrote:
| Comparable to Falcon 9? Unlikely - they've got three
| dozen Raptor engines on that thing, which alone account
| for the entire cost (not price) of a Falcon 9 flight.
| Maybe it is comparable to legacy launch providers, such
| as the Deltas and Atlases. But unlikely comparable to a
| Falcon 9 launch, even considering the larger payload.
| avmich wrote:
| In https://payloadspace.com/starship-report/ the cost of
| Falcon-9 launch is estimated as $15M. One Raptor is less
| than $1M, but full Starship has 39 Raptors.
|
| Starship will be much more attractive when it will become
| fully reusable though.
| dzhiurgis wrote:
| You are launching 8x more payload vs ~15 reuses of
| Falcon9
| ncallaway wrote:
| > but for near-term needs like deploying bigger Starlink
| satellites and their moon lander contract they could
| probably power through without reentry survival
|
| Starlink sat deployment, probably. I'm not convinced on the
| moon lander contract though. Each mission requires the moon
| lander itself, plus a number of tanker launches to refuel
| the moon lander. I think it's something like 8-15 tanker
| launches.
|
| If each of those tanker launches is an expendable vehicle
| that's... probably economically _survivable_ , but
| definitely not sustainable.
| generalizations wrote:
| Though, if the tankers are expendable they won't have to
| reserve fuel for the landing, and the number needed to
| refuel would probably be at the lower end of that
| estimate - maybe even 6-10?
| imtringued wrote:
| If you can't reuse the boosters, then a series of
| Starship launches to the moon will cost as much as one
| SLS. The complex launch architecture demands reusability.
| It's a deal-breaker without it.
| DarmokJalad1701 wrote:
| They can launch payloads that bring in revenue while working
| on that problem. There is a good chance they put a bunch of
| Starlinks on the next flight.
| throwuwu wrote:
| Exactly, they've reached feature parity with large
| expendable launch systems so they can piggyback paying
| customers with a high risk threshold (starlink) on flights
| they'd be doing anyways. Given their cadence this phase
| won't last long, they'll likely achieve at least one
| successful landing next flight.
| ortusdux wrote:
| They have also been eager to launch version 2.0 starlink
| satellites, but they don't fit in the falcon fairing. The
| first couple batches of those would be test articles as
| well, so I'd be surprised if the next starship launch
| doesn't a few on board.
| dotnet00 wrote:
| They've been launching a version of the v2 sats that do
| fit in the Falcon 9 fairing and supposedly have all the
| functionality of the larger versions. The issue is that
| F9 can only carry ~24 of those at a time, which slows
| down the pace of expansion a lot.
| ortusdux wrote:
| The new 'Pez dispenser' on the starship is designed for
| the full sized V2 sats, which are about 2x the mass of
| the V2 minis.
| gorkish wrote:
| Yes this would all be true, if it were true. It is likely
| to become true at IFT-4 but they are very demonstrably
| not quite where you say they are.
|
| This was still a suborbital flight and they cannot do
| much of anything that is commercially practical on
| suborbital flights (like launch satellites, even if they
| raise their apogee). They appear to have not had good
| control authority in coast and reentry. They did not do a
| relight/deorbit burn test that is likely an obstacle to
| tackle before they can make orbital flights. I assume
| we'll get some confirmation about these things soon
| enough, but please, you can be optimistic without being
| hasty.
| DarmokJalad1701 wrote:
| > This was still a suborbital flight and they cannot do
| much of anything that is commercially practical on
| suborbital flights
|
| If they had flown a slightly steeper ascent and burned
| for a little longer (possibly a minute if not less), they
| would have ended in a stable orbit. Not doing that was
| intentional.
|
| They do not need engine relight capability to reach orbit
| - plenty of orbital rockets exist that cannot relight
| their final stage.
| bdamm wrote:
| Yes, but the point was that they can't launch starlinks
| or just about any commercially meaningful payload until
| they are reliably in orbit, and they can't reliably get
| into orbit until they demonstrate at least one relight,
| because they need to reliably re-enter the atmosphere for
| the reusability tests.
|
| So they are at least one more launch away from launching
| starlinks.
| DarmokJalad1701 wrote:
| > commercially meaningful payload until they are reliably
| in orbit,
|
| Which then can do without a relight.
|
| > and they can't reliably get into orbit until they
| demonstrate at least one re-light
|
| And part of testing deorbit/landing capability _includes_
| testing that they can relight the engine.
|
| So they _could_ launch the next one with Starlinks
| (possibly test articles of those as well since no full-
| size V2 satellites have been laucnhed yet). Get it into
| orbit and include a deorbit burn /re-entry as part of the
| flight plan. If the latter part somehow still does not
| work out ... they still got Starlinks into orbit. And
| they now have more data to fix it on the next flight.
| They already have several vehicles lined up for static
| fires and flight tests.
| bandyaboot wrote:
| They won't put starship into orbit until they can test
| relight. They won't risk, nor would they be allowed to
| risk putting it up there without a demonstrated ability
| to bring it back down in a controlled manner.
| Laremere wrote:
| They might do one to test deployment, but it'd be a
| throwaway. Their relight test was skipped (not said why),
| so they still don't have confirmation they can control
| where Starship re-eneters. Until that happens, it's very
| unlikely they'll target actual orbital velocity. The
| Starlink satellites do have thrusters, but they're ion
| engines, so not nearly enough thrust to get that last bit
| into orbit before they'd re-enter.
| baq wrote:
| 99% chance that they lost attitude control hence couldn't
| point the business end towards wherever they wanted to.
| we know they can relight the engine on the booster and we
| know they can relight for landing burns.
|
| no surprise if the next launch has a couple pre-
| production big starlink birds.
| LorenDB wrote:
| On the contrary, they absolutely had attitude control.
| Otherwise reentry would have seen the ship tumbling out
| of control and quickly breaking up. Instead, SpaceX was
| able to begin a controlled reentry in the upright
| position, indicating nominal orientation performance.
| baq wrote:
| they were tumbling, just slowly. they started reentering
| side first. that it broke at 65km was unsurprising -
| shuttle experienced peak heating about there.
| Plasmoid2000ad wrote:
| I'm no so sure, it at least looked like it was tumbling
| before and throughout re-entry. If they had attitude
| control, I think they would have at least stopped the
| visible rotation at some point before re-entry?
|
| I'm not sure why the ship not immediatly breaking up, but
| eventually breaking up is proof that they at attitude
| control - especially against what the live feed showed -
| rotation.
| dotancohen wrote:
| > If they had attitude control, I think they would have
| at least stopped the visible rotation at some point
| before re-entry?
|
| Maybe they thought the flaps would help stabilize once
| hitting some atmosphere. In fact, that seemed to happen
| though not before quite a bit of plasma cooked the
| unshielded side.
| Laremere wrote:
| My bet on the re-entry failure is that they have really
| poor attitude control. They definitely had some, but you
| can also see at different points that the plasma was
| shifting directions. At T+46, it was doing a spin as the
| first plasma started to show. At T+47, it was going down
| on the edge of the heat shields. At T+47:40 it appears to
| be going down engine first.
|
| Moreover, I'm guessing the reason they skipped the mock
| re-entry burn was due to not being able to settle the
| propellant. Though it's really hard to tell if the
| turning of the Starship was to rotate which side was
| getting heating from the sun, or if it was spinning out
| of (or with less than desired) control.
|
| Tim Todd noticed that the gas thrusters were icing over
| and then releasing the ice. So it's a reasonable guess
| that this was part of the issue, but that's leaning even
| more into speculation territory.
| Laremere wrote:
| I just noticed that I typed "Tim Todd" instead of "Tim
| Dodd". It's past the edit period so I shall forever live
| with this shame. In my defense, I was on 5 hours of sleep
| so I could watch the launch.
| bdamm wrote:
| You are a contemporary yet timeless sort of gentleman.
| Well done.
| numpad0 wrote:
| I'd speculate one of main tank bulkheads breached and gas
| kept leaking from payload door which overpowered RCS.
| Then, during reentry, the vehicle briefly managed to
| regain attitude by aerodynamic forces on the flaps, but
| became north-northwest aligned and broke up.
| bitcurious wrote:
| > know they can relight the engine on the booster and we
| know they can relight for landing burns.
|
| Do we know that? Booster crashed into the water at full
| speed; landing reignition failed.
| apendleton wrote:
| They did demonstrate this during their Starship-only
| bellyflop/landing tests a couple of years ago. This
| wasn't in space, though, obviously, and wasn't after an
| extended coast period. So... we know they can relight
| them under at least some circumstances, but whether or
| not they can under _these_ circumstances is maybe
| unclear.
| toomuchtodo wrote:
| As long as it is profitable when thrown away, the math
| works. Remember, until Falcon 9, they were always thrown
| away (except for Shuttle). Even if not profitable in the
| short term, the delta between cost and breakeven is an
| R&D expense.
|
| Payload able to be delivered to orbit safely and
| insurable? _Ship it_. The more you do, the faster you get
| better.
| bell-cot wrote:
| If their cost per kg to orbit, with total loss of both
| Booster and Starship, is substantially lower than any of
| their competitors - then it is success, and recovery is just
| icing on their profit margins. Er, cake.
|
| (And would be very cool marketing and PR, obviously. Not that
| SpaceX has much need for either of those.)
| avmich wrote:
| No quite; even if 1st and 2nd stages deliver cargo to orbit
| cheaper than competition, you still has to make sure there
| is enough demand to pay back the cost of Starship creation.
| That demand may require not just being cheaper, but to
| being substantially cheaper than competition, to enable
| additional uses.
|
| What SpaceX is doing with Starlink reminds of the situation
| with early versions of Windows, when, as Bill Gates
| described, the industry wasn't keen to produce applications
| for it. So Microsoft started writing Word and Excel in
| house. Similarly, SpaceX created Starlink which needs lots
| of launches, and which couldn't exist with previous level
| of launch prices, but is able to make profits if the prices
| are as low as SpaceX can provide.
| cchance wrote:
| Re-entry is icing because every other cargo rocket besides
| falcon, lands just like IFT3 lol
| imtringued wrote:
| Artemis 5 only needs three New Glenn rockets. Artemis 3 and
| 4 need significantly more Starships.
| golol wrote:
| One technical modification: They need engine relight in orbit
| to work to deliver payloads, otherwise Starship will stay in
| orbit and they can not test reentry.
| neffo wrote:
| You need a second burn just to enter orbit. You burn at the
| top of the sub-orbital arc (opposite side of the earth) to
| enter orbit.
| exDM69 wrote:
| No, that's inefficient and real spacecraft don't do that
| for typical low earth orbits. Works in Kerbal Space
| Program, though.
|
| Normal orbital insertion is a single burn to orbit (with
| staging). With the correct initial roll and pitch, the
| spacecraft follows a perfect gravity turn and ends up in a
| near circular orbit at main engine cut off.
| dotancohen wrote:
| Do they typically burn softly until near apogee, then put
| on the power until raising the orbit on the other side to
| their current altitude? In KSP, I can easily get an orbit
| on a single burn (with staging) but getting it circular
| obviously requires adding energy at apogee.
| exDM69 wrote:
| No, most rocket engines have quite limited amount of
| throttle capability and run near maximum thrust until
| cutoff.
|
| The rocket yaws and pitches in the first seconds of
| flight while the vehicle is still subsonic, then flies a
| gravity turn trajectory at zero angle of attack (facing
| the direction of travel) at near maximum thrust. Any
| errors accumulated during early part of the flight will
| be corrected by adjusting the timing of the second stage
| cutoff based on radar tracking.
|
| The initial pitch over is just a few degrees off
| vertical, but must be precise to a fraction of a degree
| (KSP tolerances are higher due to small planet).
|
| You can get a pretty good circular orbit in Kerbal Space
| Program with one burn if you do a few attempts and trial
| and error binary search for the optimal initial pitchover
| angle, but it's very difficult to do without throttling
| the 2nd stage burn. If I recall correctly, the MechJeb
| mod can do a precise single burn to orbit.
| dotancohen wrote:
| Thank you. Yes, I figured that real life engines could
| not throttle enough for the maneuver as stated. I am
| familiar with the gravity turn, but I just don't see how
| energy can be added continuously, uniformly right up to a
| circular orbit. But I've not really put much effort into
| trying to understand that, I'll start looking more at
| real life pitch angles at various altitudes. Maybe I just
| need to start that gravity turn sooner - you mention that
| it already starts in the first few seconds. Thank you.
| exDM69 wrote:
| In vanilla KSP1 with a reasonable orbital launcher, fly
| up to 1000m altitude and tap D on your keyboard 1 to 10
| times. Then hands off until 2nd stage and then throttle
| down to avoid overshooting the apoapsis.
|
| Finding the correct number of key taps to get the right
| pitch angle is the key. The throttle can only help so
| much.
| ericbarrett wrote:
| MechJeb + Realism Overhaul offers a "Primer Vector
| Guidance" ascent controller that (I think) is based on
| the space shuttle's Powered Explicit Guidance. It's
| definitely designed to work with more realistic
| spacecraft; it can ullage with RCS, doesn't need to
| throttle, etc.
| numpad0 wrote:
| IIUC real launchers do a single burn to orbit because S2
| TWR is not very high and relight is finicky. Launchers
| that has relightable S2 and/or hypergolic S3 routinely do
| circularization burns.
|
| There are reasons "apogee" is more recognized word than
| "apoapsis".
| lupusreal wrote:
| > _There are reasons "apogee" is more recognized word
| than "apoapsis"._
|
| What are you getting at? The -gee suffix means Earth.
| Apogee is apoapsis of an orbit around Earth. People
| playing KSP speak of apoapsis because Kerbin isn't Earth.
| numpad0 wrote:
| IRL they always did and therefore discussed "apogee
| kicks" after payload release into elliptical transfer
| orbit(literally GTO). That's where I'm getting at.
|
| If you think about it, there can't be an ellipse that
| intersects a circle while also being fully encompassed by
| the latter. That's to say the periapsis can't be higher
| than the maneuver altitude that the off-apsis burn takes
| place as the other guy is suggesting.
|
| On real rockets they add small shelf-stable stage such as
| the spinny boi Star-48 or the notoriously narcoleptic
| Fregat, inside fairings between S2 payload interface to
| actual payload, or let the payload pull itself into the
| final orbit at a great expense.
|
| Yes, you can keep the S2 burning all the way to Ap and
| then burn at -45deg at Ap to deform the ellipse back into
| a circle, or fly a by the book gravity turn trajectory,
| but that's not the most energy efficient insertion, only
| what are situationally beneficial when there is land
| below and acceleration is limited.
| firebaze wrote:
| They do this _while_ performing the burn of the (in this
| case) 2nd stage. "No, that's inefficient" is misleading,
| IMHO. They also waste some delta-V by starting the
| circularization burn a little bit early.
|
| You surely know that, but mathematically it is
| unavoidable to have a 2nd burn at the apoapsis to have an
| orbit (with a periapsis > the initial launch altitude,
| minus gravity and atmospheric losses), albeit it may
| start earlier (while wasting a slight amount of delta-v).
| DarmokJalad1701 wrote:
| > You need a second burn just to enter orbit
|
| Not necessarily - it is completely dependent on the ascent
| profile. For example, during the Apollo program, the Saturn
| V would fly directly into a parking orbit and only relight
| the S-IVB for the Trans-Lunar Injection burn.
| gameshot911 wrote:
| I'm not sure the payload doors successfully opened and closed.
| Anyone have more details?
| hagbard_c wrote:
| I heard the announcement about the door opening and saw -
| what I assume to be - live images from the inside which
| showed the door first opened, then closed so it seems that
| test worked.
| MostlyStable wrote:
| Scott Manley seems to believe that there was some kind of
| malfunction with the doors[0]. I couldn't really tell from
| the video, but he certainly knows a hell of a lot more in
| this domain than I do. He does agree that overall the test
| was highly successful though.
|
| [0]https://youtu.be/8htMpR7mnaM?t=512
| bane wrote:
| Here's a fun thought, how many Starship launches would it take
| to put the equivalent mass of the ISS up in the same orbit?
| DarmokJalad1701 wrote:
| The ISS weighs ~420 metric tons. That is 2-3 expendable
| launches or 3-4 reusable ones.
| GeoAtreides wrote:
| Jesus Christ, that really puts it into perspective what a
| game changer starship is
| bane wrote:
| Now do the same calculation in units of hubble space
| telescope and james webb space telescope masses.
|
| Then look at expected reusable launch cost and figure out
| how many HSTs or JWSTs we could have put in orbit for the
| same cost.
| 93po wrote:
| JWST would also be incredibly less expensive if it didn't
| have to do the very complex folding required by smaller
| rockets
| Retric wrote:
| JWST would still have been an extremely novel and
| therefore expensive on Spaceship. We just don't build
| anything that uses that kind of sun shield or those
| sensors etc and everything needs to work on one shot,
| thus serious engineering effort.
| birdman3131 wrote:
| How much larger could we have made it still doing the
| folding on starship?
| Shawnj2 wrote:
| Launching JWST on Starship would still be incredibly
| expensive because JWST is at the Lagrange point on the
| other side of the moon and 1 starship needs like 30 other
| starships to fuel it to get there
| danw1979 wrote:
| Not just the capacity per launch but the cost per launch
| also.
| trailynx wrote:
| for comparison, building the ISS took 40 assembly flights
| [0] (36 of them from the Space Shuttle)
|
| [0] https://en.m.wikipedia.org/wiki/Assembly_of_the_Interna
| tiona...
| 2OEH8eoCRo0 wrote:
| How many launches are required to land on the Moon?
| DarmokJalad1701 wrote:
| Depends on what lunar lander hardware is being used. If we
| were using Apollo hardware:
|
| Apollo LM: 16 metric tons (landing about 5 tons on the
| moon)
|
| Apollo CSM: 29 metric tons
|
| The third stage of the Saturn V, called the S-IVB, (which
| was used for the trans-lunar injection burn) weighed 123
| tons - however this was also used to get into the initial
| orbit.
|
| Starship can launch 150 tons to LEO in reusable mode or
| ~200 mt when expended. The Saturn V was able to launch 141
| tons to LEO. So it should theoretically be possible for
| Starship to launch an LM+CSM stack with an S-IVB with
| enough fuel for a trans-lunar injection burn. Then fly the
| rest of the mission as in Apollo.
|
| Or we can refuel the Starship a few times in LEO using a
| bunch of re-usable flights and land 100 tons of payload on
| the lunar surface. The latter is probably cheaper and
| simpler at this point.
| GuB-42 wrote:
| According to this:
| https://youtu.be/OoJsPvmFixU?si=Df6Eq9uq6IJCApUs&t=1730
|
| Six... eight... more like twelve... at least 15
| rtkwe wrote:
| Big things they still need to hit are soft splashdown of both
| stages because recovery and reuse are critical to the economics
| of Starship. From the stream it looks like they had barely any
| engines light during the landing burn and I could see several
| missing tiles on the second stage. Way fewer were missing
| though which is a bonus, last time they were visibly missing a
| lot of tiles even before they lost the stage.
| jkjkjjjkjkj wrote:
| Well, the second stage definitely needs to survive re-entry if
| it wants to carry passengers. But it seems to work as-is for
| orbital cargo.
| mgiampapa wrote:
| Passenger rating isn't even in the cards for Starship for a
| long time. You ride to LEO on a Falcon-9 with a proven track
| record for the foreseeable future.
| avmich wrote:
| "Foreseeable" is roughly "five years"? Starship HLS (Human
| Landing System) is currently planned to land on the Moon,
| with people, in 2026. It may very well slip a year, two or
| three - but landing on the Moon this decade still seems
| quite possible. Or you consider "passengers" different
| enough than "crew"?
| mgiampapa wrote:
| Yes, landing on the Moon without an atmosphere is vastly
| different from orbital flight on earth and has an
| entirely different risk profile.
| grecy wrote:
| Interesting Asterix on that is the humans will only be on
| Starship from Lunar orbit down to the moon surface and
| then back to lunar orbit again.
|
| No humans aboard during Starship launch, transit to and
| from the moon or re-entry.
|
| (For completeness, humans will do all that other stuff
| aboard SLS and Orion. Starship literally only ferries
| them down the moon and back up again)
| avmich wrote:
| Yes, but HLS is just one example. In, say, ten years it
| may look very possible that Starships with people will
| fly on LEO. Is it beyond foreseeable future?.. I just
| don't understand why such a pessimistic estimate.
| mgiampapa wrote:
| In my view, since I was the one that said it, anything
| more than 5 years away is perpetually 5 years away until
| it's been proven. Yes, eventually when Starship has
| enough launches and a track record it will get human
| rated by NASA to carry astronauts. This is the only
| actual certification for human space flight worth paying
| attention to right now. It's possible to get on a rocket
| otherwise, but the US government isn't going to pay for
| the ride. Getting flight certified by NASA is expensive
| and requires a level of experience with the vehicle that
| doesn't make sense for at least 5 years given we have a
| cheap and safe ride to LEO via Falcon / Dragon. Nobody is
| going to rush human flight on Starship, it's only going
| to have people on it once it's already in space.
| avmich wrote:
| I'll still take this as progress. With thermonuclear
| reactors it's perennial 20 years, similar for flying
| cars, in-house robots, manned flight to the Mars, so 5
| years as a stand-in for "foreseeable future" sounds like
| a good step ahead.
| kristianp wrote:
| Maybe the words "success" and "failure" are too difficult to
| shoehorn into describing these tests, especially with the first
| two tests.
|
| "Great progress" is a good intermediate.
| HeyLaughingBoy wrote:
| When you write a test case, you define what "Passed" means.
| If this test flight overall meets SpaceX's definition of
| "Passed", then it was a success, regardless of what anyone
| else thinks it should mean.
| pclmulqdq wrote:
| If your test case for left pad passes when it outputs a
| string of the right length, your boss is going to judge
| whether it's a good test case. Since this is all being done
| on federal grant money, it's legitimate to have higher
| expectations. This test was good, though - the previous two
| were disappointing.
| f-securus wrote:
| Holy cow. How are people downplaying something so
| revolutionary. Without those other tests SpaceX wouldn't
| have done what it did today and they show progress each
| step. They are doing what nasa couldn't (send stuff to
| space orders of magnitude cheaper) because they aren't
| afraid to blow stuff up.
| 2OEH8eoCRo0 wrote:
| They haven't gotten to the revolutionary part yet (fuel
| tankers in orbit, raptor relight, reusable first stage,
| reentry).
| f-securus wrote:
| Re-using rockets isn't revolutionary?
| pclmulqdq wrote:
| Nobody has done anything revolutionary and nobody has
| gotten to space an order of magnitude cheaper. The _best_
| estimates of SpaceX 's cost advantage per kilo put it at
| 30-50% better than a Soyuz.
|
| The Starship program so far has soaked up as much money
| as SLS, and hasn't even left orbit.
| jiggawatts wrote:
| They did several revolutionary things with starship:
|
| Full-flow staged combustion metholox engines.
|
| Stainless steel construction.
|
| Biggest rocket to have ever flown.
|
| Highest thrust at launch of any rocket by a factor of two
| or so.
|
| Live streaming of reentry via a space Internet network.
|
| Etc...
| zer0c00ler wrote:
| I think each test served exactly its purpose and it's
| incredible to see the rapid progress. Unclear why you
| believe the first two were not a success at all? Did you
| expect a novel vehicle like this would just work the
| first time?
| pclmulqdq wrote:
| I do. SLS, Vulcan, and most other rockets from reputable
| space companies have worked first time.
| bandyaboot wrote:
| The test flights have been right in line with how spacex
| does development and testing. I'm confident that everyone
| involved with granting them that money knew this going
| in.
| tempaway444641 wrote:
| T+37: Seems a little turny-aroundy in orbit there
|
| and a bit "small-pieces-falling-offy"
|
| Still, good job getting it there
|
| T+43: seems to be turning around a bit too much for something
| thats got heat shields on one side and is about to re-enter
|
| T+45: flaps moved, maybe that is supposed to get it the right way
| round, I get it now - it uses the flaps to orient for re-entry
|
| T+46: the little bits of debris must be tiles coming off
|
| T+46: flap glowing red, can see plasma (edit: spacex tweeted a
| video of this bit, its quite something
| https://twitter.com/SpaceX/status/1768279990368612354 note the
| camera position moves because the camera is on one of the forward
| flaps)
|
| T+47: "biggest flying object ever in space" uh-oh
|
| T+47: serious re-entry flames
|
| T+48: loss of signal
|
| T+54: still no signal
|
| T+62: saying they lost signal via starlink and TDRS at same time
| so maybe that was the end of it
|
| T+65: confirmed lost during re-entry
|
| T+67: the presenters all eat a large pie. each.
| namaria wrote:
| I'm still in awe that I got to watch a reentry live stream just
| now. I wish I could tell my child self what wonders were in
| store. Watching humanity progress in real time is amazing.
| AnimalMuppet wrote:
| Kids. I got to watch a moon landing live. (Not a stream, and
| crummy resolution, but still...)
|
| [Edit: I meant to be talking smack a bit, but don't let me
| ruin your enjoyment of the really amazing things that are
| happening now.]
| twh270 wrote:
| Yeah, it's pretty awesome to watch "the first" of
| something! I wasn't born early enough to watch the moon
| landing, but I did watch the livestream of the first
| successful landing of a Falcon 9. Watching that bit of
| science fiction turn into reality was one of the more
| memorable moments of my life.
| namaria wrote:
| It's all good, I feel like we're all kids when we wonder
| about the universe
| pixl97 wrote:
| >T+46: the little bits of debris must be tiles coming off
|
| Seemed like ice to me, which itself can be it a problem. The
| vehicle didn't seem very stable even before this point so I'm
| wondering if we're getting ice build up on the cold gas
| thrusters which changed the control dynamics keeping the ship
| from flying stably.
| tempaway444641 wrote:
| Yeah could be. Some of the debris looked very specific in
| shape though. On some shots of starship you can see missing
| tiles (not many though)
| K0balt wrote:
| It looked to me like a good portion of the debris was in
| fact tiles. It also seemed to me that there were
| significant attitude control deviations, both of which
| might have been significant factors in the unplanned
| disassembly event.
| rtkwe wrote:
| Right after the engine cut-offs for the second stage from the
| first burn you can see at least one tile missing and during
| the burn before that I also saw some dark flecks fly off.
|
| It certainly looked like there was either a fairly continuous
| firing of the cold gas thrusters, a stream from the second
| stage engines, or some atmospheric effects from being in such
| a low orbit.
| jboggan wrote:
| That re-entry video was quite amazing and beautiful.
| fernandotakai wrote:
| those plasma views when starship was coming into atmosphere were
| absolutely mind blowing.
|
| it makes a lot of sense to use starlink for this, but it never
| ever crossed my mind.
| kkoyung wrote:
| Having those plasma views in _livestream_. It is incredible.
| schnitzelstoat wrote:
| Yeah, in HD. It's sci-fi stuff.
| chinathrow wrote:
| As of today, it's the new normal!
| mrandish wrote:
| The new _norminal_!
| yreg wrote:
| Just like the first belly flop video.
|
| The thirty seconds from 1:00 are unreal.
|
| https://www.youtube.com/watch?v=gA6ppby3JC8
| chasd00 wrote:
| yeah that was really cool, it looked like an artist rendition
| of what it could look like hah. I'm looking forward to high-
| res photos of those views.
| ordu wrote:
| The booster puncturing spheres of clouds on a way back was
| awesome also.
| danw1979 wrote:
| That was my highlight of the test: live video of the biggest
| rocket booster hitting the ocean at 1000km/h.
| tempaway444641 wrote:
| video: https://twitter.com/SpaceX/status/1768279990368612354
|
| Note the camera moves because its also on a flap
| mrandish wrote:
| Indeed! I just want to thank SpaceX for giving me yet another
| _" This looks like insane Hollywood special effects but it's
| real"_ moment.
| renewiltord wrote:
| Mind-blowing stuff. Breathtaking to be honest. Live video is such
| high quality. Sci Fi made real.
|
| Looks like Starship lost but so much farther than before. This is
| incredibly exciting stuff.
| iamthirsty wrote:
| Unfortunate that it was lost on re-entry. Super glad most of the
| mission was a success.
| BenoitP wrote:
| FR24 shows a Dassault Falcon 900EX doing circles around the
| expected Starship re-entry location (Perth to Perth flight plan):
|
| https://www.flightradar24.com/MXJ/345b8f09
| mikeyouse wrote:
| Not looking good - Returning to Perth now.
| grecy wrote:
| From a safety perspective, how does that work?
|
| This is obviously a test, and safe to say the vehicle was out
| of control and not entirely predictable. I realize they
| wouldn't fly into the actual predicted landing area, but just
| being close must be a risk.
|
| Would the flight crew on that plane literally be scanning the
| sky above them to make sure they're not in the direct path of
| whatever comes down at whatever speed?
| terramex wrote:
| If onboard computer would sense that Ship is going somewhere
| it should not be it would trigger FTS (Flight Termination
| System) and destroy it with debris falling into Atlantic
| Ocean (exclusion zone was there as well).
|
| Once Ship finished burn it simply had to land in predicted
| landing area in Indian Ocean, it did not have enough fuel on
| board to significantly change trajectory even if computer
| went crazy.
| BenoitP wrote:
| I guess some risk analysis can be made with the plane's and
| Starship's cross-section.
|
| Let say they are cubes of 30m each. The expected area where
| they might both be present to be a 5km square. That's a
| 0.000025 chance of collision at most; and I suppose the plane
| is away from the center of the expected Starship Gaussian.
| I'd personally ride in that plane and risk that, even to just
| to get a glimpse of the reentry.
| grecy wrote:
| that.... makes a lot of sense. Thanks.
|
| Somehow I was thinking it was super risky to be in the
| general area, but your numbers show that is clearly no the
| case.
| mrandish wrote:
| Interesting that there was a flight sent to be in the
| splashdown area. My guess would have been there's not much
| engineering/scientific benefit to getting in the neighborhood
| of the splashdown. Maybe some footage could be gotten just for
| curiosity but at this early stage of re-entry testing of such a
| new and different vehicle I suspect the odds of being close
| enough to acquire decent air-to-air visuals would be pretty
| low.
|
| Maybe the flight was an attempt to get close enough for a
| stored telemetry downlink post-rentry blackout but pre-
| splashdown?
| travisgriggs wrote:
| I was surprised that during the initial ascent footage from the
| fin-cam, you can see that the grid fins are out. Do they not fold
| back on ascent? Or possibly drag on one side to arc over? Just
| seems weird to have your "drag device" deployed during ascent.
| malfist wrote:
| They're control surfaces, they help keep the pointy end up and
| the flamey end down
| grecy wrote:
| They fold in/out on Falcon 9, but for the starship booster the
| decided it's not worth it. The extra weight and complexity to
| fold them in/out doesn't provide enough of a benefit. Elon
| talked about it a couple of years back on one of Everyday
| Astronaut's videos.
| Laremere wrote:
| Grid fins aren't drag devices. They are control surfaces. As
| long as they are oriented so the fins are aligned with the
| airflow, they have no effect on orientation. The benefit of not
| folding them in is one less part that can fail. There might be
| a slight reduction in drag by folding them in, but not much and
| apparently not worth it.
| dylan604 wrote:
| I'm guessing 33 Raptor engines won't feel the effect of
| whatever drag those fins might produce. Instead, they'll just
| drag that drag into space
| russdill wrote:
| The side edge of the grid fin may have more surface area than
| edge on.
| panick21_ wrote:
| Not sure they can turn that far.
| russdill wrote:
| I'm saying if you could fold the grid fin, the surface
| area presented may be as high or higher than the surface
| area presented when unfolded.
| dotnet00 wrote:
| I think that between the high TWR allowing the vehicle to spend
| less time in the thicker parts of the atmosphere and the lower
| pressure 'wake' the ship on on top would produce, there isn't
| as much drag over the fins as one might think. IIRC it was one
| of their various "delightfully counter-intuitive" discoveries
| during earlier testing.
| ironyman wrote:
| https://en.wikipedia.org/wiki/SpaceX_Starship_integrated_fli...
|
| Mission summary including timestamps
| 2OEH8eoCRo0 wrote:
| > Raptor in-space relight demo | No attempt
|
| That was a big one to not attempt. Why didn't they attempt it?
| cubefox wrote:
| Possibly because they partially lost attitude control.
| ta1243 wrote:
| "Starship did not attempt its planned on-orbit relight of a
| single Raptor engine due to vehicle roll rates during
| coast"
|
| https://www.spacex.com/launches/mission/?missionId=starship
| -...
| sashank_1509 wrote:
| So FAA cleared SpaceX and then within a few days they completed
| their launch pretty successfully by all accounts. So does that
| mean SpaceX could have launched a while back with no issues and
| were just waiting on the FAA? Did the FAA literally just slow
| down progress?
|
| Not a good look on the FAA, they should just let SpaceX do what
| it does at the speed they want. If they cannot add any value to
| this engagement, the least they can do is to not subtract value.
| pixl97 wrote:
| When you're launching the largest and heaviest rocket ever made
| not running headlong into creating the biggest fuel air
| explosion is part of the regulatory agencies job. The first
| launch was pretty wildly out of control so everyone wants to
| make sure the rocket explodes when told if it doesn't go where
| it's supposed to.
| s1artibartfast wrote:
| I think you touch on the issue of managing public perception
| as part of the FAAs job.
|
| In general the public is not monolithic when it comes to
| this. Many people would ecstatic with the biggest fuel air
| explosion and thought Launch 1 was great while others were
| aghast.
|
| Some people even think rockets shouldn't be developed at all.
|
| As a result, you see regulators trying to find a line between
| covering their asses from blowback from different groups of
| constituents.
| dotnet00 wrote:
| It's a bit of a complex interplay. If the FAA were finishing
| their investigations very quickly, SpaceX could be more
| aggressive with their testing. But on the other hand, as SpaceX
| gets a better read on how long the FAA might take, they time
| their readiness to when the FAA will be done.
|
| For example, here they waited ~1 week between Starship being
| ready and done with a wet-dress rehearsal. If they knew that
| the FAA would be finishing earlier, they'd try to get through
| the WDR earlier. But since there's plenty of other development
| and testing to do on the ground, they just do that in the
| meantime.
|
| The FAA delays were more of an issue around IFT-1 because they
| really couldn't proceed on much without knowing how all the big
| systems they built would perform, they would've been working
| blind (and considering how the launch infrastructure needed
| further strengthening, doing too much more without that data
| would've probably been a waste of money). That isn't really the
| case now, while they wait on the FAA they can focus on the
| payload bays, refining the control systems, building the second
| launch tower etc.
| ceejayoz wrote:
| > Did the FAA literally just slow down progress?
|
| Doesn't appear so, no.
| https://en.wikipedia.org/wiki/SpaceX_Starship_integrated_fli...
|
| > On March 5, 2024, SpaceX announced that they were targeting a
| launch date of March 14, 2024, pending regulatory approval. On
| March 13, 2024, the FAA granted the launch license for IFT-3.
| jumpman_miya wrote:
| Man this has me crying like a baby. I do not know why.
| tompark wrote:
| Did anyone notice at around T+30:16 the cargo door was almost
| shut when it looked like it popped out of place. Then the view
| suddenly switched to an external camera.
|
| Am I wrong?
| eagerpace wrote:
| Yeah, seems like something that needed to be closed even if it
| were on the cool side of the reentry.
| pfdietz wrote:
| It got much farther than IFT-2, and exposed new problems, which
| is the purpose of a test flight. This seems like a success.
|
| Things will only be bad if some problem is exposed that doesn't
| look solvable.
| was_a_dev wrote:
| I'm happy they have some data with respect to re-entry. It
| would have been nice to see the vehicle survive for longer, but
| there's something to go forward with.
| ShitHNsays wrote:
| So the space chode successor made another, uhh, flight. Good
| thing for the environment in that Texan protected habitat it
| didn't burst at the seams on launchpad, like so often.
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