4 ms·

> #1 turned off the trim system and continued the flight without incident. (This flight is almost never mentioned, as it doesn't fit the narrative.) I.e. they

> #1 turned off the trim system and continued the flight without incident. (This flight is almost never mentioned, as it doesn't fit the narrative.) I.e. they piloted the plane without the MCAS, which they were not trained to do. The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it.

salawat 5y ago
This is the part that bugs me as well. When you have to disable MCAS, you're flying a plane you've not trained for. Particularly given the fact MCAS featured prominently in the landing regime.
throwaway0a5e 5y ago
>I.e. they piloted the plane without the MCAS, which they were not trained to do. The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it. This kind of hand wringing shares a non-negligible part of the blame for why hundreds of people are dead. If Boeing had been allowed to say "of course our new engines are gonna pull the nose up a little harder, throttle back and climb slower if you don't like it" the MCAS system would never have been built to be the safety critical boondoggle it became. The plane itself handled just fine but the problem that they tried to solve with MCAS is that it wasn't identical to the prior 737. Even the most incompetent professional 737 pilot can fly a 737 that wants to <insert control input here> slightly when <insert other control input here> so long as they're expecting it (remember, they train for this stuff in simulator and most of these pilots are certified for multiple different aircraft) but just letting the pilots deal with it wasn't an option because the regulations disallowed that due in large part to decades of "people are just dumb cogs" type thinking. And once the airplanes started falling out of the sky nobody could say "just turn of MCAS, it won't handle the same but close enough" because Boeing, the airlines and the FAA were all so balls deep in the lie they'd look like idiots if they changed their opinions and thanks to the society we've cultivated nobody is willing to be the first to break formation because that's who gets targeted by the bulk of the fallout.
- Gwypaas 5y ago
  That is not correct, it simply would not be certified as airworthy without it. Differences in feeling between airplanes are fine. Airbus has a system of common type ratings allowing fairly quick transitions. Especially between A330, A340 and A350.[0] > MCAS is a longitudinal stability enhancement. It is not for stall prevention (although indirectly it helps) or to make the MAX handle like the NG (although it does); it was introduced to counteract the non-linear lift generated by the LEAP-1B engine nacelles at high AoA and give a steady increase in stick force as the stall is approached as required by regulation. > The LEAP engine nacelles are larger and had to be mounted slightly higher and further forward from the previous NG CFM56-7 engines to give the necessary ground clearance. This new location and larger size of nacelle cause the vortex flow off the nacelle body to produce lift at high AoA. As the nacelle is ahead of the C of G, this lift causes a slight pitch-up effect (ie a reducing stick force) which could lead the pilot to inadvertently pull the yoke further aft than intended bringing the aircraft closer towards the stall. This abnormal nose-up pitching is not allowable under 14CFR §25.203(a) "Stall characteristics". Several aerodynamic solutions were introduced such as revising the leading edge stall strip and modifying the leading edge vortilons but they were insufficient to pass regulation. MCAS was therefore introduced to give an automatic nose down stabilizer input during elevated AoA when flaps are up. http://www.b737.org.uk/mcas.htm#background http://www.b737.org.uk/mcas.htm#background [0]: https://www.airbus.com/en/products-services/commercial-aircraft/cockpits https://www.airbus.com/en/products-services/commercial-aircr...
landemva 5y ago
"The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it." That summarizes why the plane did not go through a new type certification process - avoid costs of pilot training. Boeing instead painted over the differences (larger fans mounted forward) with software to make it feel the same.

salawat 5y ago

This is the part that bugs me as well. When you have to disable MCAS, you're flying a plane you've not trained for. Particularly given the fact MCAS featured prominently in the landing regime.

throwaway0a5e 5y ago

>I.e. they piloted the plane without the MCAS, which they were not trained to do. The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it. This kind of hand wringing shares a non-negligible part of the blame for why hundreds of people are dead. If Boeing had been allowed to say "of course our new engines are gonna pull the nose up a little harder, throttle back and climb slower if you don't like it" the MCAS system would never have been built to be the safety critical boondoggle it became. The plane itself handled just fine but the problem that they tried to solve with MCAS is that it wasn't identical to the prior 737. Even the most incompetent professional 737 pilot can fly a 737 that wants to <insert control input here> slightly when <insert other control input here> so long as they're expecting it (remember, they train for this stuff in simulator and most of these pilots are certified for multiple different aircraft) but just letting the pilots deal with it wasn't an option because the regulations disallowed that due in large part to decades of "people are just dumb cogs" type thinking. And once the airplanes started falling out of the sky nobody could say "just turn of MCAS, it won't handle the same but close enough" because Boeing, the airlines and the FAA were all so balls deep in the lie they'd look like idiots if they changed their opinions and thanks to the society we've cultivated nobody is willing to be the first to break formation because that's who gets targeted by the bulk of the fallout.

Gwypaas 5y ago
That is not correct, it simply would not be certified as airworthy without it. Differences in feeling between airplanes are fine. Airbus has a system of common type ratings allowing fairly quick transitions. Especially between A330, A340 and A350.[0] > MCAS is a longitudinal stability enhancement. It is not for stall prevention (although indirectly it helps) or to make the MAX handle like the NG (although it does); it was introduced to counteract the non-linear lift generated by the LEAP-1B engine nacelles at high AoA and give a steady increase in stick force as the stall is approached as required by regulation. > The LEAP engine nacelles are larger and had to be mounted slightly higher and further forward from the previous NG CFM56-7 engines to give the necessary ground clearance. This new location and larger size of nacelle cause the vortex flow off the nacelle body to produce lift at high AoA. As the nacelle is ahead of the C of G, this lift causes a slight pitch-up effect (ie a reducing stick force) which could lead the pilot to inadvertently pull the yoke further aft than intended bringing the aircraft closer towards the stall. This abnormal nose-up pitching is not allowable under 14CFR §25.203(a) "Stall characteristics". Several aerodynamic solutions were introduced such as revising the leading edge stall strip and modifying the leading edge vortilons but they were insufficient to pass regulation. MCAS was therefore introduced to give an automatic nose down stabilizer input during elevated AoA when flaps are up. http://www.b737.org.uk/mcas.htm#background http://www.b737.org.uk/mcas.htm#background [0]: https://www.airbus.com/en/products-services/commercial-aircraft/cockpits https://www.airbus.com/en/products-services/commercial-aircr...

landemva 5y ago

"The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it." That summarizes why the plane did not go through a new type certification process - avoid costs of pilot training. Boeing instead painted over the differences (larger fans mounted forward) with software to make it feel the same.