I didn’t fail to realize that the Boeing deliberately did not disclose the MCAS to pilots. I thought that was rather bizarre when I read about that after the Lion Air crash.
The non-Lion Air pilot who was sitting in the cockpit jumpseat on the same plane that crashed the next day, recognized that it was a runaway trim situation and correctly shut off the trim. There were 3 incidents previous to the Lion Air crash on the same aircraft that crashed. In all 3 cases the pilots successfully dealt with the condition. The 4th incident on the same plane, there was no one in the jumpseat to show the correct way to handle the runaway trim. But this begs the question. Why was a plane with a faulty AoA gauge allowed to fly 3 more times without being properly repaired? No airline in the US would be allowed to to that.
I think pilots flying for US based airlines that fly the 737 Max would correctly handle the runaway trim situations. Still it appears that the MCAS system as certified is orders of magnitude more likely to generate runaway trim situations. How a fly by wire system that was supposed to work so far behind the scenes that pilots would not be told about it, and flight manuals didn’t mention it, could be activated by non-redundant sensors boggles my mind. Quite frankly I was really shocked when I first saw the new tail for the 737 Max. It looks to be smaller than the 737 NG. That seemed to be quite a departure from the 737 NG. If I were a pilot, I think I would want to learn about what those differences were for.
Actually Southwest does have a 737 Max simulator. Guess what. That simulator has no MCAS failure modes.
The FAA need to get it’s stuff together. They risk losing reciprocity with other aviation regulators around the world.
I don’t see how this plane was rushed. The program was announced in 2011. It was studied for some time before that. The first flight was in January 2016. The first revenue flight was in May 2017. The main problem has been the limited supply of engines being produced by the CFM consortium. There are lots of 737 Max aircraft being stored without engines. Fortunately there haven’t been reports of engine reliability problems in use unlike the Pratt & Whitney Pure Power geared turbofans that have had huge teething problems with the A320 NEO. And don’t forget the Rolls Royce Trent 1000 engines on the 787. They have had huge problems with corrosion. Apparently there are issues with how they tested their engines. It is RR equipped 787’s that fly over Asia where lots of sulfur dioxide is emitted mainly form Chinese electrical generation plants and steel mills bur into the atmosphere that the corrosion issues are showing up. Guess what! The EU prohibits RR from testing their engines in Europe using high sulfur fuel. They likely would have discovered the issues in the development phase rather than after in operation.
“Why was a plane with a faulty AoA gauge allowed to fly 3 more times without being properly repaired?”
Red flag and very disconcerting.
There is debate if the AoA guage is faulty or just intermittently giving erroneous readings.
The Ethiopean Airlines CVR showed that Captain and FO had different AoA readings, That was one reason why the Captain handed control over to the FO after he thought he got the plane climbing again.
I think they will find that because they did not turn off MCAS, the Captain pulling on the yoke and changed trim only temporarily reset MCAS. After 10 seconds, MCAS turns back on and wants to trim the plane to nose down. This happened as the Captain handed controls over to the FO and MCAS re-activated and put them into a nose down situation again.
My understanding is that the trim forces can be so much that manual yoke and trim cannot overcome it.
Don’t forget, they were not far from the ground, nose down, stick shaking and warning buzzer trying to get the plane to climb. They may have forgotten about the Auto Trim Off switches altogether, resulting in their deaths.
Turning Auto Trim Off is not a 737 NG procedure....and that is a problem.
The worst problem is having MCAS use only one AoA sensor input. Two is better, but then the computer has to choose which one to believe and which one to ignore. Three is always the best because the computer can look for 2 that agree and ignore the oddball.