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by geocrasher 1906 days ago
LOTS of aircraft have a tendency to pitch up or down based on throttle. This isn't unique to the 737 MAX.

A quick google on "thrust line pitch moment" gave me this: https://www.homebuiltairplanes.com/forums/threads/thrust-ang...

  " I want to adjust the thrust angle from where it was (0° with respect to the chord line) to reduce the downward pitching moment when thrust is added (or more importantly the upward pitch moment when thrust is reduced)"
1 comments
cratermoon 1906 days ago
Not many passenger aircraft have a tendency to pitch up to the point of stalling, though.
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manigandham 1906 days ago
It does not just pitch up randomly. It does pitch more than other 737s due to engine size and placement, but that's just the specific behavior of this plane.

Stalls are not a serious problem, they're basically the first thing pilots learn to solve. And there are plenty of aircraft that are more challenging to fly. That's what training is for.

The real issue is that pilots should have full understanding of the behaviors of the airframe instead of relying on software to change it. Especially when they don't have full understanding of the software either, and the system can both override manual inputs while being susceptible to faulty sensors.

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satellite2 1906 days ago
> Stalls are not a serious problem

They account for 25% of fatal accidents [1]

[1] https://www.aopa.org/-/media/Files/AOPA/Home/Pilot-Resources...

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jrockway 1906 days ago
Seems like the vast majority of cases there are personal aircraft not piloted by ATPs. General aviation is what it is. Certainly there are airline pilots that don't recover from stalls successfully (Colgan Air Flight 3407's crew), but there are confounding factors like sleep deprivation. Personally, I worry a lot more about sleep deprivation than particular subsystems of jetliners. You can easily kill two airliners worth of people in a few seconds when you read back "hold short of runway 31R" and then just barel onto it because you're not alert.
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manigandham 1905 days ago
The source says "the overwhelming majority of unintended stalls occur on personal flights in day visual meterological conditions (VMC) under light winds". And the commercial flights are mostly part 137 (aerial application like agriculture and fire fighting).

So to add context, stalls under commercial part 135 flights are extremely rare and even less fatal. There's almost always some other compounding issue that led to the stall instead of just basic flight maneuvering.

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geocrasher 1906 days ago
Neither does the 737 MAX.
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