> the entire horizontal stabilizer needs to be moved to ensure the nose is brought back down in short order
Doesn't MCAS take a long time to significantly move the stabilizer? Like tens of seconds? It's hard to square needing to decrease AoA so dramatically with the actual mechanics of MCAS.
MCAS has a duty cycle of on 10 seconds, off five. It ramps up the degrees per activation up to a max of 2.5 degrees per activation (2.5 degrees per 10 seconds), all the way to max down trim if you let it.
Keep in mind, the entire horizontal tail plane moving has a heck of a lot more influence on attitude than the elevators.
If it were a stringed instrument, trim would be the tuning tabs at the top of the neck, the elevators would be the fine adjustment screws on the body of the instrument.
Thanks. I understand that the stabilizer is powerful. I'm wondering whether it's true that, when your plane is in that danger state of "flinging itself past critical AoA", 2.5 degrees over 15 seconds is sufficient to avoid or recover the wing stall in time to avoid terrain.
(I think the proposed software changes also reduce this control authority but I'm not sure how.)
Doesn't MCAS take a long time to significantly move the stabilizer? Like tens of seconds? It's hard to square needing to decrease AoA so dramatically with the actual mechanics of MCAS.