Originally Posted by
MechEngr
WideScreen,
They were, starting 1-10 seconds after take-off*, given a continuing stick shaker** - which
AFAIK requires two memory item steps: Disable the Autopilot and Disable the Autothrottle. They did neither one. The reasons for the requirement is simple: either the automation has pushed the plane into a stall or the instrumentation the automation requires has failed; both make reliance on the automation a bad choice. The overspeed did not happen for a long time after that; there was no conflict at the time the stall warning memory items were to be done. Had they been done there would be no overspeed and therefore no additional warning for it.
Yep, they didn't do these things, though it would not have made a difference on the final outcome. Not to say, when on full power, with the nose pointing up, close to the ground, there are good reasons to keep the automation running, so, you have brain cells to investigate what is going on.
My impression is, they would have found out (they had time, since the aircraft was perfectly flyable) and setup the return to the airport.
This issue is the conflicting indications together with the cacophony on alarms that got fired.
Originally Posted by
MechEngr
They also had access to fresh knowledge of exactly how MCAS functioned and how to handle it. This is skipped over by the Final Report, leaving the industry without a firm base to analyze what steps are required to guarantee every pilot learns and understands the information that is available.
AFAIK, they didn't. That info piece was not readily available for ET crews at that time. There were some "instructions", though (see below), these only work in a very limited circumstance. Really, turning off the electric trim in a B737-NG/MAX is not an option, the moment you get a little out of trim.
Originally Posted by
MechEngr
As evidenced by the Lion Air preliminary report, issued months ahead of ET302 one crew and a senior pilot found the plane completely flyable with MCAS nudging away; Lion Air crashed when a first officer did not continue the management the captain had been performing.
Yep, once you know how it works, it's easy. The FO didn't and there was that much of a cacophony, the captain didn't instruct the FO EXACTLY what to do, unfortunately. Though they only did have a couple of seconds to investigate, etc. Not enough time, before this became irrecoverable.
Originally Posted by
MechEngr
There is no "secret button." The trim runaway cutout switches are plainly visible and work as advertised; though earlier versions had separate channels to cutout separate inputs, the training was always (last 10-30 years
AFAIK) to cut them both rather than spend time to diagnose the exact cause of the trim runaway.
As long as you don't know how it works, it's a "secret button". Also, to be able to trim a B737-NG/MAX, you need the electric trim, the moment the aircraft is only a little out of trim. So, keeping the electric trim active was mandatory. The fact, it did need a trim-blib every couple of seconds to avoid the MCAS would take-over was NOT known.
Originally Posted by
MechEngr
Read the Final Report for both Lion Air and ET302, paying close attention to the events recorded by the FDR for all three flights.
I feel quite sad at the outcome as MCAS was not a system that failed in a way to guarantee a crash. There was a failure in human factors and it wasn't the amount or kind of alarms, but in failing to convey to the pilots what an MCAS event felt like and how they needed to always handle the stall warning immediately and never use Autopilot or Autothrottle with the stick shaker running. You might ask, why doesn't the automation shut itself off when the stick shaker is running? Because, if it's an automation failure the automation cannot be trusted to do anything correctly. At least the airplane computers cannot lock the pilots outside.
Sorry to hear, you are on the Boeing trail, that it's a pilot fault....
That way of thinking was "current", 50+ years ago. It's no longer applicable in today's busy commercial flying business. There are simply too many other (higher level) important items, to expect pilots to have to deal with something like the MCAS intricacies.
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