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Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

airandspaceforces.com

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Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#21

Post by ledauphin »

bombcar wrote: post #17
RcouF1uZ4gsC wrote: post #15

Earlier quoted context omitted.

Actually, the 737 MAX as a new plane would have been fine. The MCAS software was used to try to give it the same flight characteristics as the 737 so that existing 737 pilots did not have to get additional certification for it.

Yeah, but they didn’t just build a new plane (pilots perhaps?) and instead always seem to try to modify existing designs, which would argue that is cheaper than greenfield.

a new plane would not have been eligible for the same type certification, thus forcing all pilots who flew it to obtain the new type rating. This training is very expensive for the airlines.

in other words, Boeing's thesis was, because we (heavily) modified the 737, it's the same basic plane. The FAA accepted this argument. The FAA would never have accepted the argument that a totally new design was "actually a 737 ".

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#22

Post by SomeHacker44 »

bombcar wrote: post #17
RcouF1uZ4gsC wrote: post #15

Earlier quoted context omitted.

Actually, the 737 MAX as a new plane would have been fine. The MCAS software was used to try to give it the same flight characteristics as the 737 so that existing 737 pilots did not have to get additional certification for it.

Yeah, but they didn’t just build a new plane (pilots perhaps?) and instead always seem to try to modify existing designs, which would argue that is cheaper than greenfield.

Modifications to old certifications are subject to older certification rules. They can be flown by pilots with existing training. Thus saving money at the cost if safety and decades of improvements in technology and regulation. End of story ... And of lives.

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#23

Post by jameshart »

bombcar wrote: post #14
skybrian wrote: post #6

They say there's a lot more volume, but would it carry more weight, and where would the weight have to be placed? Why isn't this design used commercially?

It would only work for cargo and would have other issues. Almost all commercial planes are for both cargo and passengers, and you’d have to bank really slowly if that was full of passengers.

... full of paying passengers. Soldiers can just be strapped down in the dark and you can hose the decks down after landing.

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#24

Post by jameshart »

skybrian wrote: post #6

They say there's a lot more volume, but would it carry more weight, and where would the weight have to be placed? Why isn't this design used commercially?

While presumably military transport does involve moving very dense things, Some of the things the air force is called upon to transport have high volume but low weight. Like helicopters, for example.

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#25

Post by colordrops »

chrisseaton wrote: post #4
colordrops wrote: post #3

Earlier quoted context omitted.

Has it been evaluated whether any real-life evacuations were time sensitive enough to where a wide bodied plane would have resulted in more deaths? Doesn't seem like a real problem intuitively, but I don't really have any data to back that up.

Do they do all those evacuation tests with able-bodied volunteers? How would they evacuate for example five wheelchair users within the 90 seconds or whatever is required for the test?

That's what I'm getting at though. There are imagined criteria for these tests, but what has the real life situation been in actual emergencies? Have there been enough real life evacuations where getting everyone out within 90 seconds vs 3 minutes was the difference in saving many lives?

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#26

Post by lmm »

colordrops wrote: post #25
chrisseaton wrote: post #4

Earlier quoted context omitted.

Do they do all those evacuation tests with able-bodied volunteers? How would they evacuate for example five wheelchair users within the 90 seconds or whatever is required for the test?

That's what I'm getting at though. There are imagined criteria for these tests, but what has the real life situation been in actual emergencies? Have there been enough real life evacuations where getting everyone out within 90 seconds vs 3 minutes was the difference in saving many lives?

All airliner safety features are objectively pretty pointless given that cars remain legal and routine with like 100x the lethality. But yes, there have been at least a handful of cases where some but not all of the passengers were able to get out of a plane in time, particularly when the plane caught fire on landing (e.g. Air Canada 797).

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#27

Post by InTheArena »

adolph wrote: post #19
mauvehaus wrote: post #7

The KC-46 program has not gone swimmingly. I'm curious how they think they're going to get a demonstrator flying in 5 years when they can't get a tanker that's based on an existing production airframe flying on schedule. https://en.m.wikipedia.org/wiki/Boeing_KC-46_Pegasus

P8 went pretty well. Blended wing isn’t sci-fi, B2 and plenty of ucav are full flying wing. https://en.wikipedia.org/wiki/Boeing_P-8_Poseidon

Boeing was a very very different company then. I’m bullish on blended wing body, but I would have much more confidence if it were Lockheed or someone emulating the SpaceX, rapid development cycles working on this.

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#28

Post by MR4D »

An updated B2 design without stealth would probably be highly achievable in this timeframe.

The problem being a cargo plane usually wants a fast approach and takeoff to eliminate threats near the runway. I don’t know if a B2 (or flying wing in general) would be good at that.

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#29

Post by nomel »

MR4D wrote: post #28

An updated B2 design without stealth would probably be highly achievable in this timeframe. The problem being a cargo plane usually wants a fast approach and takeoff to eliminate threats near the runway. I don’t know if a B2 (or flying wing in general) would be good at that.

What about a flying wing makes the approach slow? Is there some ground effect that comes into play?

Re: Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 2027

#30

Post by chmod775 »

colordrops wrote: post #25
chrisseaton wrote: post #4

Earlier quoted context omitted.

Do they do all those evacuation tests with able-bodied volunteers? How would they evacuate for example five wheelchair users within the 90 seconds or whatever is required for the test?

That's what I'm getting at though. There are imagined criteria for these tests, but what has the real life situation been in actual emergencies? Have there been enough real life evacuations where getting everyone out within 90 seconds vs 3 minutes was the difference in saving many lives?

> 90 seconds vs 3 minutes

That's a huge difference in case of a fire. Ninety seconds of smoke filled, oxygen deprived, or hot air, and many people will make it out alive. Three minutes and most will have passed out.

There's quite a few instances of burning planes being evacuated where not everybody, but a sizeable portion, made it out. Seconds matter*.

* Almost always there was some idiots slowing everything down by grabbing their luggage.

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