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Comment by tus88 | Hacker News Reader

Because MCAS is required, unlike every other aerodynamically stable airplane that came before it.

Airbus does it too. They have several control laws that are used to provide flight envelope protection. It was the pilot's failure to understand his plane's software that caused AF447 to crash. Essentially he didn't realize that the flight control software had changed modes, that it wasn't providing the normal handling augmentations, and that his inputs were putting the aircraft into a stall, which caused the crash.

See: https://en.wikipedia.org/wiki/Air_France_Flight_447

https://aviation.stackexchange.com/questions/62338/why-did-a...

Build unstable airframes? Not outside of forward canard jet fighters.

And that pilot crashed a perfectly fine airliner after he lost situational awareness and then did the one thing you should never do - pull the steering column back in a mad panic until the plane stalls.

https://en.m.wikipedia.org/wiki/Qantas_Flight_72

Qantas Flight 72 is probably a good demonstration of why using MCAS as a band-aid for the 737 MAX's stability issues is a bad idea. One of the key reasons that fault didn't lead to a crash that killed everyone on board is that Airbus placed much safer limits on the amount of control authority their flight envelope protections had and the altitude at which they could operate.

No, in normal flight regimes, MCAS is not required. For example, it is disabled at any time, the flaps are extended, that is during starts and landings. It is only required (by law) at high angle of attacks. In these kind of flight regimes, most other airplanes also have systems to ensure their "stability". The 737 MAX isn't fundamentally more unstable than competitor airplanes with large engines.

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