Boeing's upgraded 737 Max completes first flight with media onboard

Re:Boeing's upgraded 737 Max completes first flight with med... by HPsquared on Wednesday December 02, 2020 @08:45PM (#25284262)

This is a bit of an urban myth that keeps flying around. The plane is perfectly stable without MCAS, but would have had different handling characteristics than the previous version. The purpose of MCAS was to modify the handling to match the previous plane, so pilots' type ratings would carry over with minimal retraining. At its heart, it was a (poorly implemented) kludge in an attempt to sidestep a lot of paperwork.

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Re:Boeing's upgraded 737 Max completes first flight with med... by throwaway201103 on Wednesday December 02, 2020 @09:36PM (#25284599)

You're mostly right, but it wasn't just to make it handle like the previous versions, it was to satisfy FAA certification rules on how it handled.

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Re:Boeing's upgraded 737 Max completes first flight with med... by cjbprime on Wednesday December 02, 2020 @10:29PM (#25285010)

This is my understanding too, though Boeing hasn't really come out and said it definitively. Specifically:

> MCAS was devised to fulfill an airworthiness certification condition in 14 CFR 25.173 and 14 CFR 25.175. In high angle-of-attack (AoA) flight configuration, it is required that stick force/g (the stick force necessary to produce (hold) an incremental normal acceleration of 1g) and stick movement/g (ditto mutatis mutandis) must increase (or at least not decrease) with an increase in AoA (thanks to Clive Leyman for this formulation). I understand that in flight test, in which “wind-up turns” were conducted (a turn with increasing angle of bank; an increasing angle of bank means ceteris paribus increasing AoA), this condition was not fulfilled.

-- https://abnormaldistribution.org/index.php/2019/04/30/ieee-s...

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Re:Boeing's upgraded 737 Max completes first flight with med... by Stierlitz on Thursday December 03, 2020 @12:05AM (#25285591)

@throwaway201103: “You're mostly right, but it wasn't just to make it handle like the previous versions, it was to satisfy FAA certification rules on how it handled.”

And also to stop the plane dropping out of the sky!

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Re:Boeing's upgraded 737 Max completes first flight with med... by Stierlitz on Wednesday December 02, 2020 @11:55PM (#25285541)

Boeing PR must be out in force.

@HPsquared “.. The plane is perfectly stable without MCAS ..”

NO, no, no it isn't .. doesn't matter how many different ways you re-arrange the word salad. MCAS is a software kludge to compensate for an unstable airframe

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