Re:Boeing Believed a 737 Max Warning Light Was Standard
by sowbug on Sunday May 05, 2019 @08:25PM
(#19835963)
If they're on either side of the fuselage and you're slipping, it seems like they'd give different readings. Pitots can give misleading readings if you slip away from the side they're on. I've never flown a plane with an angle of attack indicator.
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Re:Boeing Believed a 737 Max Warning Light Was Standard
by inferiorhuman on Sunday May 05, 2019 @09:18PM
(#19836155)
If they're on either side of the fuselage and you're slipping, it seems like they'd give different readings.
Which is why there's a threshold that much be crossed (IIRC ten degrees) before the disagree warning appears.
Re:Boeing Believed a 737 Max Warning Light Was Standard
by dreamcompiler on Monday May 06, 2019 @12:02AM
(#19836766)
Most of the time when you're slipping close to the ground you're going to also have flaps deployed, in which case the MCAS is inoperative. Your AOA sensors will definitely disagree, but at least the MCAS won't act on them because it doesn't act when flaps are deployed.
If you're slipping without flaps I guess it could still be a problem if the disagreement is outside the epsilon spec. I'm not sure if [normal] slip could ever cause that much disagreement.
Re:Boeing Believed a 737 Max Warning Light Was Standard
by bigiain on Sunday May 05, 2019 @08:53PM
(#19836069)
I'm now imagining a 737MAX8 in a flat spin...
(I've had the controls of a 172 and a Tiger Moth briefly, but have never _really_ flown a "real plane". I have flat spinned many many rc planes, mostly recovered fine, but also to their occasional doom...)