Originally Posted by
Smooth at FL450
Maneuvering Characteristic Augmentation System. Because of the shape of the Max motors and the fact they extend further forward ahead of the CG than other 737s, at high angles of attack the engine nacelle itself starts to produce lift which causes an additional pitch up moment. So they had to design a system to drive the nose down...
MCAS is supposed to be disabled with the flaps extended...will be curious to know the configuration of ET302 when they started to encounter issues.
Where do you guys get this stuff? When you want to push the nose down you don’t use trim, you use the yoke. MCAS trims off the increased pressures, the pilot still has to push the nose over. In the Lion Air case the AOA malfunction cause the trim to continue to run increasing nose down pressure. That was a malfunction, not the design of the system.
It was the FAA that said pilots should not be told about the system, not Boeing. Boeing didn’t want MCAS, the FAA did. The FAA said not to tell pilots because they would think it is an anti stall system that pushes the nose over and pilots would not properly recover from a stall. They were right, as evidenced in all the articles talking about the “stick pusher” and the new anti stall system, neither of which exist. Where they were wrong was not being able to see into the future where a damaged/malfunctioning AOA vane could cause that condition.