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Old 6th May 2019, 02:26
  #4971 (permalink)  
fdr
 
Join Date: Jun 2001
Location: 3rd Rock, #29B
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737D;

your posts indicate that the crew of the flights were less than competent in essence, however, you also suggest that the training standards are deficient. One specific on competency is your statement that you would respond in the event that these crews encountered by recognising the problem, identifying the cause and completing the action within "5 seconds".

Okay.

You are currently a participant in an internet multi player demonstration of Schrödinger's cat gedankenexperiment, WRT observer impact on outcomes. You have knowledge that did not exist at the time of the events, and you have time to contemplate navels and determine a course of action, and by those factors alone, you are not able to replicate the conditions existant for the crews concerned. To judge the crews timeliness or lack of understanding is fundamentally flawed scientifically if you have any intent to understand what happened in these cases. Today, possibly the crews will respond effectively to this particular problem, but given the application of sods' law, someone on some dark night is going to brilliantly apply all the prompt response that will be gained from the establishment of the corporate knowledge of MCAS, and they are going to misapply it as a slip in SA will have occurred. That is the insidious nature of the world we live in, where unintended consequences are a real outcome.

On "5 seconds", that is of course 60% longer than the out of trim case that the aircraft is certified for, so presumably your "5 Seconds" is also potentially inadequate, however I assume that you would not consider your "5 Second" response time to be incompetent?

The Boeing OEB raised after the first accident is pretty darn silent on the fact that the aircraft can enter a condition where the airloads on the stab can exceed the crews ability to effect a recovery. For that gem, you have to read the FCTM and comprehend what the weasel words there mean in the real world, that in order to recover in the severe out of trim case, you may have to let the aircraft recover towards it's trim state sufficiently to unload the stab so that the trim can be actuated. That sounds all well and good if you are not confronted with planet earth in the upper windscreen at close proximity to achieve that condition. That is pretty much an existential threat to the crew, and I would hazard that they were indeed under some stress, that you as an observer from the sideline have not had to experience when making your "5 Second" judgement on competency.

I agree that training needs to be lifted around the industry, we dont necessarily need more training, we need training that is not wasteful fo the resources that exist, as they are to day. We are currently governed by the aviation industries own version of political correctness, A.K.A. as SMS, and QA. In order to give a simplified box ticking exercise to regulators and managers, we come up with matrices and checklists that are fantastic for showing compliance, but, that is all. There is no closure of the loop on the fact that the crew may comply with a procedure or policy that in itself increases operational risk, or is impossible to do as it conflicts with the real world. The other sort of failure (think false negatives, false positives) arise when the boxes get ticked, but the impact of implementation is not observed. Our roles, policies and procedures are developed usually as bandaids on top of bandaids to reduce the risks of something, either real risk, or showing compliance (another form of risk - commercial). In all cases, however it is unlikely that the 200 hr pilot sitting in the RHS seat of the plane was the cause of the competency issues, he/she cannot be other than the logical outcome of what the industry has accepted as a good solution to unfettered growth (a cancer in effect, sounds good until the consequences start being felt).

Sully gets mentions in the conversations. The NTSB acknowledged the human in the loop issues in the response time during the public hearings and that was factored into the analysis. I would suggest that the recognition aspects of a loss of all engines event while unpleasant, is simpler than the multiple failure cues that existed on the Lion Air and Ethiopian aircraft. Rather than acknowledge the human in the loop, you have indicated that "5 Seconds" is a competent response time. I would counter that the time you suggest is arbitrary and unreasonable, and does not reflect competency, it merely reflects the opportunity you have had to consider your hypothetical response to the scenario post hoc.

As an aside, long long ago etc... I was evaluating a checker and a trainer in a sim, while they collectively beat up on a student (a B7xx line captain). They were remarkably derisive of the pilots competency. At the end of the session, I asked these aces to hop in the seats and I was going to give them a single failure well within the realms of likelihood. With a modest cross wind, as the wheels left the ground, I failed the worst case engine, from the standpoint of applied rudder at that time, I declined to use crash override to make the point. On leaving the sim session, both checker and trainer apologised to the student for their lack of respect in their comments. Point is this, humans in the loop are a fact, and it is important to recognise and respect that. Sully made a difference to the outcome, as more often than not occurs every single day in countless anomalies that the industry encounters. Humans are the strength of the system while being a point of failure, and that needs to be accepted.

Over the years, I have listened to too many CVR's and looked at too many FDR/QAR outputs to expect that any crew will achieve much in 5 seconds on a normal flight, other than pavlovian responses for failures on a TO. The highly trained response on an RTO etc is however as often as not carried out incorrectly, so I wonder if the 5 Seconds is not just a bit harsh as a standard.

A final thought: The crews encountered an unusual trim case, the checklist is for a runaway trim, yet the problem did not actually present as such, there was a trim error that occurred, but the trim responded normally to the crews trim inputs, and then after a period of time was anomalous again. That is not a simple set of facts to decipher in short order. Given their time over, I expect that the crew would follow your advice and act within 5 seconds and cure the ills of the world.

kind regards,

FDR
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