Originally Posted by
MurphyWasRight
For the NG (and theoretically reverted MAX) the stab trim runaway procedure memory items could be kept the same, simplistic paraphrase: Trim if possible, both switches to cutout.
The only change would be to add an option to restore manual electric trim once memory items were done, this would not need to be a memory item:
To restore manual electric trim set the [corect switch name] to enabled, be prepared to immediately disable if runaway trim re-occurs. Do not re-enable should this happen.
Second part covers a possible fault in either the pilot switches (highly unlikely) -or- the motor controller since power will be restored.
While I don't disagree in theory, this approach has two distinct problems.
First, as I have mentioned, there has been a very definite shift in philosophy regarding non-normal (formerly known as emergency) procedures industry wide. I don't know if the change was driven by manufacturers, regulators, operators, or some combination of the three, but it has been in place for awhile and unlikely to change. There is a very great reluctance to conduct any action that may be seen as troubleshooting a malfunction which very much includes restoring power to a system, or part thereof, that has malfunctioned. There is probably some historical safety data to back up this philosophy, but there are times when I believe it is overly constraining. Nevertheless, the intent behind most of the significant non-normals nowadays is to shut down and/or contain the malfunction and land the aircraft with what you have left.
Second, let's just say that the switchology was changed back to the NG configuration and we inserted this new step into the existing Runaway Stab Trim procedure. For the sake of discussion we will call it Step 6 since Step 5 is where the cutout switches are used. In order to get to Step 6, the pilots must first correctly navigate Steps 1 thru 5. Since neither accident crew chose to utilize the existing Runaway Stab procedure, much less work through it step by step (and particularly that very critical Step 2), then a new switch with a new step really would not have solved their problem.
As I mentioned above, new tools don't help much if they are not used or used ineffectively. The accident crews had several tools available to them that they either did not use or did not use effectively. I think a bit more time and energy should be directed to figuring out why that was the case before we go down the path of creating new tools.