Originally Posted by
Grebe
tomaski
Lets see - Assuming pilot realized he had to use trim switch to get near level trim BEFORE hitting kill switch - how long did he have ? Seems to me he had at best 5 seconds - now with a typical call - response - action - how much ' slack ' was available ??
Once the pilot is actively and aggressively engaged with using the Main Electric Trim, they have as long as they need. By design, MCAS would pause for 5 seconds every time the Main Electric Trim (yoke switch) was used, and there is no limit to how long the Main Electric Trim could be run at any one time. In theory, one long nose up trim input to put the trim back in place, then a series of short trim inputs every 5 seconds or so. The pilot could literally do this as long as they wanted until they either 1) ran the Runaway Stab Trim procedure to conclusion, or 2) slowed down to less than 250 KIAS (if not already there) and extended the flaps. Again, not an impossible situation to manage with proper information and training - and that is exactly what was missing.
If pilots were never properly trained to handle critical emergencies like engine failures and windshear during takeoff, we would not be surprised to see accidents when these events occur. But we
do train for them, pretty much every single time we go through a sim session. How often were the accident pilots exposed to a Runaway Stab Trim scenario? I haven't seen one in years, though I expect that will probably be changing.
Yes, MCAS was a crap system and never should have made it past certification. Not informing crews of its existence was borderline criminal. That doesn't mean it was not possible for pilots to have been exposed to the type of training that would have allowed them to survive this malfunction. (And before anyone jumps on this bandwagon, I am NOT blaming the pilots. The pilots do not create the procedures, the training syllabus, or the corporate culture that gives a short-shrift to safety. However, they
are products of all the above).
Specifically as to training and general operations, here are some areas that need attention:
- Automation policy. By their very nature, some malfunctions strip away the automation. The pilots need to be able to operate without automation/normal law AND respond to a critical malfunction. That only comes from regular practice flying without these aids. If it is an airline's policy that pilots operate at the highest levels of automation all the time, we should not be surprised when they become task-saturated when the automation is no longer there to assist them.
- Overly-scripted training. Pretty much every where, training has become a series of scripted malfunctions that are known in advance. Multiple malfunctions are not presented. There is little, if any, use of surprise or ambiguity. Real life does not go by script, nor is there any natural law prohibiting multiple or ambiguous malfunctions.
- Over-reliance on procedure, not enough big picture. Procedures are a pilot's bread and butter, and should not be disregarded lightly. However, every manufacturer will also state that they cannot devise a procedure for every situation. In certain situations pilots need to recognize when a situation does not fit a specific procedure (rather than going heads down looking for a procedure that does not exist), and rely on basic airmanship and systems knowledge to do what is necessary to stabilize the situation. If this concept is not instilled into flight crews, then they be poorly equipped to navigate the unexpected.
A thorough accident investigation provides an opportunity to identify and correct deficiencies throughout the entire chain of events. Yes, Boeing is responsible for the most egregious lapse in the chain, but there are other issues at work here and ought to be addressed as well. The problem, of course, is that the additional training outlined above will require an investment of time and money, and airlines are extremely cost-driven enterprises. They will be very reluctant to make this investment without outside pressure.