Yo gums, # 342.
Re Airbus certification, your ‘waivers and exceptions’ (#31)j. In practice these were alternative means of compliance for existing regulations, or proposals for new ‘equivalent level of safety’ justified by many years of research, system demonstration, and well argued reliability studies, etc. Thus over time, Airbus rewrote ‘the book’ - an expensive, international ‘gamble’, but one not planned to depend on training for exceptional circumstance and the variable human pilot.
As for equivalence in stick force approaching the stall - essentially not required because of the level of protections.
# 309 / 313,
‘The training position’, yes difficult to understand, even if officially declared.
Separate out the situation after MCAS fix from the problem of a deficient trim runaway drill.
MCAS II will not move the stab to an unreasonable angle due to system failure - within the bounds of certification requirements. Thus MCAS would be a background function like STS; little training requirement.
Trim runaway. Where is the limit point where the stab angle prevents recovery; speed, ht, cg, wt, thrust, manoeuvre. If not known, many test flights required to identify the boundary conditions.
At lesser stab angles how effective is the elevator, the practicality of manoeuvre procedure - speed, ht, etc, and dependence on ‘training’ for that. What is the certification acceptability of mitigation options; limit trim range, accepting flight envelope restriction; reduce the stab effect with aerodynamic change; improve elevator effectiveness; what determines an acceptable change.
What credit can be taken for crew intervention to inhibit elect trim before the limit point. Less than might be hoped for in a ‘training’ option after the accidents. This point further challenges the FAA for harmonised world opinion on Max return to service; independent action would be unacceptable both for FAA image (save face) and Boeing world wide sales.
The Max does not have a ‘trim fail’ alert, thus the rare failure situation has to be deduced. No guarantee of situation recognition or choosing the correct drill due to a range of HF considerations.
Worst case, there may not be any ‘training’ solution for trim runaway, as much as operators and pilots think otherwise.
_ _ Then there is the NG _ _