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Comment by gruez | Hacker News Reader

But it is? I think the parent was talking about:

>Travis is unequivocal in his assessment of the Boeing 737 MAX. “It’s a faulty airframe. You’ve got to fix the airframe [and] you can’t fix the airframe without moving the engines” back and away from their current position.

>The root problem with the engine-forward design is “once this thing pitches up, it wants to keep pitching up,” said Travis. “That’s a big no-no,” he continued, because pitch-up on an aircraft increases angle of attack.

https://www.eetimes.com/software-wont-fix-boeings-faulty-air...

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FYI - Background on the guy being quoted

"Gregory Travis, a veteran software engineer and experienced, instrument-rated pilot who has flown aircraft simulators as large as the Boeing 757"

I know a few veteran software engineers that are instrument-rated and frankly I'm not sure I would listen to any of them over the FAA or aeronautical engineers. Probably good for some perspective, but not exactly a great source for determining if an airplane is "aerodynamically flawed by design".

I agree with you, aerodynamics and airframes are not something so trivial to understand.

"who has flown aircraft simulators as large as the Boeing 757"

Talk about a big aircraft simulator, those that I know are the size of a car, not of a 757 (jk)

That article, and Gregory Travis' assessment, offer zero actual evidence that the design is unstable. Lot of hand waving and "the engines are different so it must be dynamically unstable" but no actual evidence, which is obvious because no independent engineer/pilot is going to be able to effectively assess the upset aerodynamics of an airliner and come to a different conclusion than both the FAA and EASA about whether or not the aircraft is dynamically unstable.

He's somewhat right on other details, but that doesn't make his assessment of the aerodynamic issues correct.

Airfoils pitch up by default. Its how they work.

Aircraft are designed to not let that happen in an uncontrolled fashion. Software has been used to do this since the advent of computers in airplanes

Maybe we should also start boycotting A320neo's too

https://www.flightglobal.com/programmes/a320neo-also-potenti...

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