3 ms·
The fix means MCAS doesn't activate unless two sensors roughly agree, and it only activates once, which means that the plane is still controllable with just the
by cameldrv 7y ago
The fix means MCAS doesn't activate unless two sensors roughly agree, and it only activates once, which means that the plane is still controllable with just the yoke after MCAS activation. MCAS will also deactivate if the yoke is pulled back (questionable IMO, since it is supposed to compensate for mishandling), and you can leave the electric trim on and undo what MCAS did without fear of it activating again.
IMO the risk of a mistaken activation that leads to an accident is extremely remote with these changes.
- peteradio 7y agoI thought the MCAS would typically be activated while the pilot would already be pulling pack on the yoke. So I'm a little confused under what circumstances MCAS would ever activate. Does it activate while yoke is pulled back but the pilot can additionally yank harder to deactivate?
- cameldrv 7y agoYes, it typically would. There's something called an aft column cutout switch which deactivates nose down trim if you're pulling back on the yoke with a certain amount of force. They're proposing to use this switch to deactivate MCAS. I'm unsure how much force it takes to activate this switch, but it seems to me that this makes MCAS less useful for its intended purpose, and that's why I said this decision was questionable.