Lionair was very unfortunate as no one knew what MCAS was however they failed to miss that maybe they have effectively runaway trim 22 times and did not follow the runaway trim procedures. Plus they were possibly dispatched with faulty equipment and the preceding flight should have done a lot more to warn the next flight.
They can be excused for not interpreting an intermittent
moving trim as continuously
moving trim (which is what the runaway trim checklist calls for].
That it may have been dispatched with possibly faulty equipment, became only apparent once airborne. The AoA sensor was replaced before flight, but that did not seem to have fixed the problem. But that was only clear once airborne. Apparently Boeing did not provide instructions for an end-to-end ground test of the AoA system.
ET302 who should have know the proper procedures to deal with an MCAS fault by the time of the crash apparently forgot the procedures and failed to keep the plane in the proper speed range.
They DID follow uptrim instructions, and they DID use the cut-out switches. So the pretty much DID follow proper procedures.
We don't know if it was crew intervention which cut the uptrim short prior to cut-off switches. Uptrim stopped at 2.3 degrees elevator angle. In fact, all four up trim actions stopped at 2.3 degrees stabilizer angle. Coincidence . . . ? Perhaps. Fact that it was crew action that stopped uptrim premature and thus did not follow procedure? No.
Yes, they did turn it back on. But that could be an action of desperation. If they felt they were going to crash because of heavy out-of-trim condition, and they were unable to move the manual wheel by hand, then they can be excused for turning it back on.
I'm at total loss why one does not keep an open mind and try to understand why the crew decided for such actions. Instead, the crew is thrown under the bus without sufficient data. And Lionair Maintenance crew is also thrown under the same bus.
Again, I'm not claiming the cockpit/maintenance crew did not make any mistakes. Perhaps the main responsibility does lay with them. But we don't have conclusive evidence for such. Until such time, it is heartbreaking that they are put under the bus, when they can't defend for themselves having paid the ultimate price for not being able to control the plane.
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"