[HN Gopher] Air Force funds 'blended wing body' design for long-...
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Air Force funds 'blended wing body' design for long-range, fuel-
efficient flight
Author : webmaven
Score : 47 points
Date : 2023-08-19 18:32 UTC (4 hours ago)
(HTM) web link (www.popsci.com)
(TXT) w3m dump (www.popsci.com)
| b800h wrote:
| It looks like Thunderbird 2.
| killjoywashere wrote:
| Is the B-21 not a blended wing body?
| whalesalad wrote:
| Reminds me of the X33, a program I remember my dad was working on
| during my childhood like 20+ years ago.
| https://en.m.wikipedia.org/wiki/Lockheed_Martin_X-33
| micah94 wrote:
| Looking at the cost spent back then vs. what this startup is
| getting, it doesn't seem like the JetZero guys have even a
| remote shot at making this happen.
| heisenbit wrote:
| Isn't such a design a recipe for lot's of ice getting into the
| engine in the winter if one is not super careful?
| kevin_thibedeau wrote:
| This is a superior design for operating off unpaved airstrips.
| If the landing gear is robust enough, this could handily
| supplement the C130's capabilities. They can always place
| heaters on top to manage any ice accumulation.
| thrill wrote:
| Ice usually forms on the leading edges, so if they are kept
| warm it will greatly reduce this risk.
| ledauphin wrote:
| there will be any number of design issues for them to solve and
| this will certainly be one of them. it doesn't seem
| insurmountable, though.
| JimtheCoder wrote:
| No. Why would it?
| ledauphin wrote:
| this was a common problem with the older tail-mounted
| engines. ice would come off the wings during takeoff and go
| straight back into them.
| m3kw9 wrote:
| How
| Animats wrote:
| Nice. NASA and Airbus have both flown blended-wing unmanned test
| aircraft.
|
| Not sure what role this serves for the USAF. It's a transport.
| Wider loads? Stealth?
|
| The US has had total air superiority in every conflict since the
| Korean War. That's over. The Ukraine war makes it clear. Against
| a competent opponent, most of what flies will die. There are just
| too many man-portable and truck-mounted systems that can take
| down aircraft. Zipping over hostile territory in helicopters is
| pretty much out. Flying big, fat transports over contested
| territory is out. Anything that flies over hostile terrain had
| better be able to hide, evade, counter, and fight back.
| coryrc wrote:
| Russia would fall like Iraq if we were to attack. Their ground-
| based anti-air would be hit as soon as even one missile is
| fired, every radar would be hit within minutes of powering on,
| their aircraft wiped out as soon as they were within range.
| With air supremacy we'd be able to fire a precision strike on
| every piece of active artillery and supply truck. They'd be
| left with nothing but men starving in trenches and running out
| of bullets, waiting for death as the sappers close in. It's a
| crying shame we don't send Ukraine even a tenth of our
| equipment.
| enterprise_cog wrote:
| The is the kind of delusional thinking that has NATO forcing
| Ukraine to use western strategy and then getting slaughtered
| for it.
|
| The US has never defeated a peer army since WW2, in which the
| USSR did most of the work. Russia has fifth gen fighters, the
| S400, and very capable EW and artillery. To pretend they
| would roll over is pure fantasy.
| xvector wrote:
| They wouldn't roll over but they would get crushed. Our
| BVR, cyber, and stealth capabilities far exceed theirs.
|
| In any case, we will never fight a hot war with a nuclear
| armed country ever again. Nuclear deterrence works, and the
| nuclear bomb has thankfully ended modern warfare between
| nuclear-armed countries.
|
| The era of superpowers sending men off to die is over, at
| least between nuclear-armed countries (but not so much
| between a nuclear and non-nuclear country.)
| xvector wrote:
| Ukraine used to be one of the most prolific black market
| military arms dealers.
|
| We should absolutely avoid sending Ukraine any modern
| equipment. As soon as the war is over, they'll sell it on the
| black market to countries that will gladly reverse engineer
| what we've built.
|
| And as an aside, I have no interest in funding proxy wars
| with my tax dollars. Let's not return to a Cold War era.
| Entering this conflict was absolutely absurd.
| luuurker wrote:
| An Ukraine that relies on the West for most of its
| equipment, is under Russian threat, and wants to join the
| EU/NATO will go around selling the West's equipment? Makes
| little sense to me.
|
| The West, and more specifically the US, is doing what they
| said they would do if Russia invaded Ukraine. This was done
| publicly and apparently privately too. So if this is a
| proxy war, then it's different from most proxy wars.
|
| I don't like war, but when you have someone that wants to
| expand their borders, sometimes you save a lot of money and
| lives by ending the problem at the start. If Ukraine goes
| well, why not do the Baltics next? What about all those
| ethnic Russians in need of "saving" in Kazakhstan? It might
| even give China some ideas. So be careful: by not doing
| anything and saving your precious tax dollars, you might
| end up spending more in the future.
|
| Wars of expansion should be costly and expensive, otherwise
| everyone would just start wars.
|
| And that cold war era... isn't that what's we're already
| walking to with China? The sanctions, China's claims in the
| South China sea, etc? Russia in Ukraine are just a side
| show.
| topspin wrote:
| > Not sure what role this serves for the USAF.
|
| Long range anti-ship missile deployment over the Pacific. A
| design like this can cover large areas and deploy autonomous
| weapons from long range.
|
| Weapon development of the US military is almost entirely
| focused on China and it's growing fleet. There are several air
| launched anti-ship missile platforms under development right
| now, including stealth and hypersonic missiles. The US is
| looking for an efficient, long range, high endurance standoff
| bomber for these systems. It doesn't need stealth; they'll
| operate from behind air defenses. It needs high efficiency,
| large fuel capacity and large payload capacity.
|
| And that is exactly what you're looking at here.
| anonymoose4 wrote:
| All of the above, you can't wage an air-war without tankers,
| logistics, and large, antenna covered advanced warning and
| control aircraft (see the AWACS). It's well known that the CCP
| has specifically targeted development of long-range air to air
| missiles so that they could target these types of aircraft
| behind the front line.
|
| Unfortunately I'm less than optimistic about this particular
| program actually producing a functional aircraft. The company
| here is asking for way too little time and too little money to
| produce a full-sized manned demonstrator IMHO. Especially for a
| company that has no track record of actually producing full-
| scale, manned aircraft. It seems like they're trying to get
| additional private investment to build their demonstrator but
| who knows.
| notahacker wrote:
| > The US has had total air superiority in every conflict since
| the Korean War. That's over. The Ukraine war makes it clear.
| Against a competent opponent, most of what flies will die.
|
| Not sure how you work that out. The state that spent half a
| century focusing on air defence to take out the USAF hasn't
| even substantially reduced the pathetically small and outdated
| fixed wing capability of the Ukrainian air force, and neither
| side has done much damage to the other side's airborne
| logistics, which is where this would fit. It's not been a great
| war for helicopters, but neither this project nor the US
| fighter capability that their superiority rests on is going
| anywhere close to frontline portable air defence systems.
| ggm wrote:
| It used to be said this would fail in passenger markets because
| windows. The reality of long haul travel these days is that
| windows are really only "I can lean here" choices which restrict
| access to the aisle, for any trans-oceanic journey.
|
| For domestic flights, I am sure there are window seat aficionado
| who will continue to pay for window in flight. For everyone else,
| and by current seating maps there are a LOT more of them, this is
| just a non issue.
|
| If a BWB design permits reasonable density, aisle access, fuel
| efficiency and a pleasant flight experience (speed, noise) then
| I'm all for it.
|
| If it has to be a freight or logistics/materiel/fuel aircraft for
| the forces before general service, so be it.
| usuallyalurker wrote:
| BWB aircraft have a few more issues than just a lack of window
| seats.
|
| They require a higher angle of attack on take-off and landing,
| and, with passengers sitting much further from the centerline
| of the aircraft than on a conventional design, passengers are
| subject to much more g-forces during roll maneuvers.
|
| The second issue can be mitigated by avoiding rolling the
| aircraft and/or by performing less aggressive rolls, but the
| first issue is something passengers will just have to deal with
| if BWB passenger aircraft become a thing.
| twic wrote:
| I wonder if you could tilt everyone's seats forward during
| takeoff and landing. I've seen very high density seating in
| the far east where people are virtually standing. Maybe the
| seats could start off that way, stay that way through takeoff
| and ascent, then gently lower to a normal posture in level
| flight.
| pcardoso wrote:
| Like the pendolino trains? Perhaps it could work, but will
| make the seats more complicated.
| e40 wrote:
| It's been many years since the window next to me was open. So,
| I totally agree. And for the last flight I took, the windows
| were a real PITA, since too many people had them open and there
| was wicked glare. A good 30-60 minutes I spent bobbing and
| weaving to avoid it being in my eyes.
| bilsbie wrote:
| Maybe we'd gain enough space for a designated viewing area
| passengers could visit.
| Rebelgecko wrote:
| Or maybe put up partitions in the middle of the plane with
| digital "windows" embedded inside
| TrainedMonkey wrote:
| I love your optimism. There are already designating viewing
| areas and bars for people who shell out first class $$$. But
| vast majority of people happen to be rational economic agents
| who choose lower price tickets. So the reality is - there
| will just be more seats.
| mikepurvis wrote:
| Also, the best viewing is typically at landing and takeoff
| when everyone needs to be seated anyway, so I expect it'll
| end up as a selection of outdoor camera feeds that are
| available from your seat-back display.
| TulliusCicero wrote:
| Perhaps on a few planes, but for most, economics means it'll
| make more sense to just put more seats there.
| moffkalast wrote:
| If this is the only practical solution for hydrogen fuelled
| aircraft, then it can't fail in passenger markets because there
| will be no other alternative to compete against once kerosene
| is too ecologically taxed.
| twic wrote:
| If you can make carbon-neutral hydrogen, you can combine it
| with atmospheric CO2 to make synthetic hydrocarbons (or
| methanol) that are carbon-neutral. There's an energy cost to
| doing this, but I'm willing to bet it far outweighs the costs
| of running an airliner on hydrogen.
| jaipilot747 wrote:
| Is there even a hydrogen turbojet engine?
| twic wrote:
| Maybe not in service, but it's been done:
| https://www.reuters.com/business/aerospace-defense/rolls-
| roy...
| moffkalast wrote:
| Afaik it's one of the three H2 airframe options Airbus is
| pursuing.
|
| https://www.airbus.com/en/innovation/low-carbon-
| aviation/hyd...
|
| The general idea is to use liquid H2, like the old KN-88
| design.
|
| https://en.wikipedia.org/wiki/Kuznetsov_NK-88
| xwdv wrote:
| It would fail because people farther from the center of the
| plain would feel more extreme movement as the plane banks on
| turns.
| barnabask wrote:
| Maybe that's where the luggage should go then...?
| pintxo wrote:
| The real problems seem to be the outside dimensions (primarily
| width) of the BWB and the question of how to evacuate such a
| geometry effectively.
| marcosdumay wrote:
| Well, you also have more places to put evacuation corridors
| and extra doors.
| notahacker wrote:
| There are fewer viable spots to put evacuation doors than a
| conventional tube. The greater internal space means a lot
| more potential redundancy and width and not necessarily
| more distance for evacuation routes, but traditional
| airline economics means packing it with seats.
| OldGuyInTheClub wrote:
| Here's Jack Northrop's view of a flying wing passenger plane.
| There's a longer version somewhere but I can't find it. Fitting
| that JetZero is teaming with Northrop Grumman/Scaled Composites
| on this. I wonder how the workshare divides.
|
| https://www.youtube.com/watch?v=JMTwQ9b5hvk
| notahacker wrote:
| > If it has to be a freight or logistics/materiel/fuel aircraft
| for the forces before general service, so be it.
|
| The challenge for that is economic: those use cases which are
| generally filled with adaptations of older generation aircraft
| at the moment probably don't pay back the R&D costs of the
| programme. Especially since a viable civil aircraft programme
| also involves worldwide line maintenance capability, a liquid
| aftermarket etc.
|
| Blended wings are are not a novel idea, and the major
| airframers have produced multiple concepts, often combined with
| theoretically much more efficient open rotor engines. The first
| attempt at a blended wing passenger aircraft was actually over
| 100 years ago (it was years ahead of its time... and it crashed
| on its first flight). But there are a lot of challenges other
| than the passenger experience characteristics people have
| already mentioned: instead of a simple tube, you now have a
| broad internal space that needs bracing in a way which doesn't
| add weight or negate space advantages, and novel designs
| greatly increased uncertainty in an industry whose safety
| record relies on predictability. And there's commercial
| conservatism in an industry whose customer base invests
| billions in new airframes on the expectation of commonality
| with existing airframes, phased replacements over predictable
| replacement cycles etc, and where the _second_ entrance to the
| market sector might well be the most successful....
|
| Military use involves completely different economics, but for
| related reasons the anticipated greater fuel efficiency is
| rarely a big deal for the military. Still, if the military
| write blank checks, that leaves scope for prototypes that
| airline executives might struggle to say no to
| neltnerb wrote:
| > Military use involves completely different economics, but
| for related reasons the anticipated greater fuel efficiency
| is rarely a big deal for the military.
|
| I think this assumption is wrong, for airplanes. Higher fuel
| efficiency means longer range for the same amount of fuel, so
| it's an increase to range for the same weight carried (or an
| increase in weight carried to the same range, presumably). I
| think this is extremely important to the military.
| notahacker wrote:
| It's not completely useless, but the US military's existing
| transport aircraft are not exactly pushing the boundaries
| of fuel consumption. A regular 777 freighter will get quite
| a bit further. Ultimately the military don't care about the
| cost, have many refuelling options, and are relying on much
| shorter range aircraft in other aspects of any conflict.
| Plus unlike other areas of aviation, if you solve a range
| problem with a bigger fuel tank, you don't get beaten to
| death by the bean counters.
|
| That's quite different from an airline, where a 20% saving
| in their largest expense against a 3% margin in a price
| competitive industry is game changing
| ge96 wrote:
| Imagine if it's designed like this:
|
| ----------------
|
| and you're seated here
|
| --------|-------
|
| Uh pardon me, excuse, pardon me... to get out
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