Everything I’ve read is rather anecdotal, as is my experience. My first calling was aeronautical engineer and F15 driver, but neither happened. Still, the interest kept me keen to the evolution of aeronautical design.
When I read that the 737 MAX was NOT a new plane but a redesign - smaller wing and bigger engines on the same airframe - I was not alarmed. The fact that the pilots I know are not concerned demonstrates a distinct dichotomy between what we know of the planes here in the US (no reports that I’m aware of filed with the FAA regarding MCAS problems) vs. the experience of these foreign pilots in the same aircraft.
A technical article I read early on stipulated that there was a single AOA sensor feeding data to the MCAS system and it is that engineering that I cited as a failure. If there are two sensors as another FReeper cited, then certainly there are more serious issues at hand. Everyone interested in aircraft knows of the problems they had with stable flight in the early F22s (oscillation from pilot input); this could be a similar scenario. However, what concerns me are the repeated citations of “training”.
If a pilot has to disengage a safety system which was installed for reasons that remain unclear, well...you aptly-outlined the concerns and I agree.
My hunch is that the wing is too small (designed for fuel efficiency) and that the engineers were afraid the planes would be prone to stalling...harkening to your other question.
Certainly ‘something’ showed up in flight testing which prompted the addition of MCAS.
Still, I’m not aware of a single incident in the US as described overseas other than pertaining to the autopilot alone; that’s a curiosity.
My hunch is that the wing is too small (designed for fuel efficiency) and that the engineers were afraid the planes would be prone to stalling
I agree partially...The wing redesign and the larger engines (which necessitated placement change on the wings) resulted in an aircraft that has stall issues with flaps up. When the design engineers identified the problems is still TBD. If the issue had been raised in the design phase, then MCAS could (and should) have been designed into the flight control software and not as an add-on system.
...a distinct dichotomy between what we know of the planes here in the US (no reports that I’m aware of filed with the FAA regarding MCAS problems) vs. the experience of these foreign pilots in the same aircraft.
I believe this is directly attributable to aircraft maintenance and pilot proficiency (training). I would be shocked if a US airline would allow an aircraft to fly with a known AOA system malfunction. US airlines have excellent training systems and own their own FAA level D simulators.
A technical article I read early on stipulated that there was a single AOA sensor feeding data to the MCAS system and it is that engineering that I cited as a failure.
Kudos to you for this observation...
Here's what I believe happened: The flaps up stall issue was discovered late in flight test program, most likely with a lot of finger pointing. The design engineers would have proposed a fully integrated MCAS system. This would have necessitated a re-write of the flight control software and a re-start of the flight test program...very expensive and would cause late deliveries (also expensive).
So management dictated an add-on MCAS which would be tested separately. If I were the chief engineer on the 737 MAX,I would have put my badge on the program manager's desk and walked out the door and hired a good lawyer.
I have a lot more to say about the designed MCAS system, but will save that for a later post.