MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures

[fdr]

Originally Posted by PEI_3721

HighWind, # 371,
A clear and balanced summary; I agree, although the future might not be the simple either-or alternatives.
The Max might have the simplest route. If trim does not meet the certification requirements and was a contribution in two accidents, keep the Max grounded until both MCAS and the trim system are improved.
The NG could be a simple logical argument, fails to meet requirements, ground the aircraft until improved. However, an ‘emotional’ but logically inaccurate argument based on ‘no accidents so far’, could allow the aircraft to remain in service, although the risk of failure is the same.
This choice has potential for splitting the regulatory authorities, purist vs practical, but could be managed with compromise. Everyone might wish to avoid using the piloting contribution in recognition and inhibition as a permanent solution.
If the NG is easier to recover than the MAX (effect of aero differences), then it could be argued that alleviation with pilot recognition and action to mitigate risk could keep the aircraft flying until the trim system is modified. There may be similar contributions from restricting wt, cg, and of course lots of training.
If the NG is more difficult, then the industry faces a pivotal point in certification and risk management, where short term compromise could be based on definitions of safety, ‘what we are doing’ vs ‘what we have’, and of course timing of modification.
The critical factor depends on who makes the decision and how is this presented; not Boeing, ideally FAA in conjunction with (all) other authorities; but then few things are ever ideal.
fdr, #373,
But ‘The Max is able to be flown safely without doubt.’
There is always doubt, particularly when considering human performance. This is the judgement which the authorities have to make, and with a background of two recent accidents to bias thoughts

The difficulties that beset the crew of both the accident aircraft were the result of inadequate knowledge and awareness being imparted to the crew. This state of affairs resulted from the OEM complying with the constraints that were imposed by the airline customers, that additional training would come at a cost. Not doing the training or awareness related to the design changes came with its own painful cost to all concerned. The comprehension of the dynamics at play are now known, and that provides the basis of awareness training to mitigate the risks that exist in the aircraft design. The MCAS needs design change, however the risk exposed by the second accident is that the limitation of the manual trim necessitates dedicated awareness training for the crew on that aspect irrespective of the MCAS design change.