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

airandspaceforces.com

41–50 of 114 posts

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

#41
A tanker is a good fit for a blended wing body. Fuel efficiency is important for that mission, fuel tanks can be easily adapted to the odd shape (compared to cargo), and fuel doesn't care about the bobbing up and down in turns that comes from the wide hull shape (compared to passengers who don't like about that).

Reconnaissance would work too.

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

#42
I thought the issue was that it was hard to pressurize a blended wing design. All pressurized planes are pretty much a tube shape, which are easier to design to endure metal fatigue and lots of pressurization cycles. The skin of an airliner is 2-4mm thick, I think you would need a substantially thicker skin for this shape.

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

#43
post #42

I thought the issue was that it was hard to pressurize a blended wing design. All pressurized planes are pretty much a tube shape, which are easier to design to endure metal fatigue and lots of pressurization cycles. The skin of an airliner is 2-4mm thick, I think you would need a substantially thicker skin for this shape.

But do you need to pressurize it? Only the crew space needs that which could be a small/short tube in the middle right behind (and including) the cockpit.

The fuel tanks don’t care. They’re not pressurized on a normal design. The cargo may not need it either.

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

#44

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

No one is expected to really believe that schedule. It's just an imaginary number so that they can get Congress to allocate enough money to start the development program. Just the way the game is played.

And I don't even blame the Air Force for deliberately underestimating. They have a legitimate need for this aircraft and the existing fleet has been worked to death.

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

#45
post #17

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.

It wasn't Boeing that was trying to save money themselves- it was Boeing trying to save airlines money. There are hundreds of thousands of people today who can fly a 737, and mechanics who can fix a 737, etc. The airlines wanted to get the better fuel efficiency from modern engines on a plane that everyone already knew how to fly and fix. Boeing actually started with a clean sheet design, tried to pitch it to airlines, the airlines didn't bite, so Boeing gave them what they wanted- the same plane but more fuel efficient. It was a huge fiasco, but it was about leveraging the advantage Boeing had in users, not saving on development costs.

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

#46
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?

> where would the weight have to be placed? In the body?

I meant that there might be balance issues. You wouldn't want something heavy placed far out towards the wing.

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

#47

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?

Not only is the test with able bodied people, they also are permitted to practice first to make the time.

But - the test handles this by only giving them 90 seconds. In the real world it would take far longer, but rather than testing a longer, more realistic test, they do a really fast one instead.

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

#48
post #12

Earlier quoted context omitted.

If that were true why did we get the 737 MAX?

Not sure if you're being sarcastic or not, but I'll bite: The 747 MAX that killed 346 people in two separate accidents and was grounded for nearly two years and cost Boeing 10's of billions of dollars in fines, cancelled orders, etc.? It is perhaps not the best example of modifications to an existing design.

Don't you mean 737 MAX or is that some other plane?

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

#50

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

Corrected the title for you: "Air Force Plans New Blended Wing Body Cargo/Tanker Aircraft by 3027"
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