Originally Posted by
GordonR_Cape
MurphyWasRight
To their credit, I would assume that the runaway trim procedure was written considering the entire flight envelope. Statistically this would be more likely to occur at altitude, rather than close to the ground, where the aircraft spends a limited time. Not a great assumption, but in the normal scenario, there would be more time for recovery procedures.
The fact that MCAS triggered shortly after takeoff, made the outcome diabolical, when the other factors came into play. If MCAS triggered at altitude, the outcome would probably be more benign, with time for the yo-yo unloading technique.
Perhaps this lack of foresight led to the blandness of the emergency AD. Prior to ET302, almost nobody would have believed that the same outcome could be triggered by two consecutive AOA sensor failures at the same stage of flight, and disaster still not be prevented by the suggested actions.
It can also be argued that checklists and training should consider the worst possible time for an occurrence. How often do you get engine out drill in sim while cruising along?
Takeoff/landing is much more dynamic than cruise so more likely for something to fail so statistics could be misleading.
Sadly the AOA sensor failures were not at same stage of flight, Lion Air had a bad sensor for the entire penultimate flight, which if corrected would have prevented the Lion air accident.
ET had an event at takeoff, either a bird strike or a latent fault literally shaken loose.
Both of course lead to disaster shortly after takeoff when MCAS was unleashed.
Hard to get past the feeling that the 'blandness' (good description btw) was part of an effort to preserve the "no changes no training" company line on the MAX.