How to save your ass if the Boeing 737 MAX you're flying decides to nosedive

Note how the floof perked up when the trainer said, “…the now infamous MCAS”.

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Nobody is ever over Macho Grande

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Upon review, I am so dead.

the spinning disks at their knees are the manual stabilizer controls

Also not a pilot, but I believe these are actually called trim wheels. Keeping a fixed wing aircraft in a specific configuration for example straight and level flight is harder than it looks. If you make any change to the aircraft’s configuration, say extending flaps, it will significantly change the aircraft’s attitude so that you are no longer straight and level but slightly off in one direction or another. A gust of wind is more than enough to affect the attitude. Almost always the aircraft ends up “drifting” slightly up or down a little. Even if your vertical speed is only slightly off perfectly level flight, after 5 or 10 minutes, instead of flying at your air traffic control assigned 20,000ft you will have drifted to 20,100ft which could get dangerous. When flying manually (not using autopilot) it is almost impossible to maintain straight and level flight using the stick alone and it is a lot of work constantly trying to make tiny adjustments and almost always overcompensating because it’s difficult to to make such tiny adjustments with the primary flight controls. The trim provides a more finely tuned set of controls so that making big changes to the trim wheel only slightly changes the aircraft’s attitude. This makes flying much less difficult and less work overall and is really required to get any fixed wing aircraft into a solid stable attitude. Then, if it starts to drift a little, you adjust the trim a little and you should be back to where you want. There are trim settings for elevators (those are the trim wheels you can see in the video), rudder, and throttle, but the one used most frequently during flight is the elevator trim. The wheels provide a manual override if the electronics for the trim system fail to work properly. They also provide visual clues (notice the white stripe on the wheels) that autopilot is making adjustments and the magnitude and speed of those adjustments.

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Soooo… Don’t understand any more about planes, might go find some more Mentour Pilot just to keep watching a cute redhead with an accent explain complicated things.

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CAM 1: [Pilot flying] Losing control of trim. Can you find that YouTube video?
CAM 2: [Pilot monitoring] The Mentour one we watched the other week?
CAM 1: Affirmative.
CAM 2: Got it. I had it bookmarked. That dog is so cute … Look at his little face. Look at his face!
CAM 1: Never mind the dog. Just fast-forward to the bit where he says what to do.
CAM 2: Skipping dog. Searching …
CAM 1: Nose still dropping.
CAM 2: Shit. Shit. Shit.
CAM 1: What’s happening?
CAM 2: I went too far. It’s started playing another video.
CAM 1: Well, go back then!
CAM 2: It’s playing an ad. I can’t skip the ad for another 30 seconds.
CAM 1: Swipe backward.
CAM 2: Fuck. Now it’s showing me a neo-Nazi video about Comet Pizza.
CAM 1: Shit. Try to find it on Daily Motion or something.
CAM 2: “This video has been removed due to a copyright claim by Sony Music.”
CAM 1: We’re fucked, aren’t we?
HOT 1: [Terrain Alert Warning System] Terrain. Pull up. Terrain. Pull up.
CAM 2: Youuuutuuuuuuubbbe!
HOT 1: (sound of TAWS continues, along with stick shaker noise, until impact)

Recording ends.

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Brilliant. Needs many more likes.

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Flip these two switches DOWN. Then, fly the plane manually. Why does everyone think that software is necessary to fly these planes?

BTW, the procedure is supposed to be committed to memory by the pilot for this procedure, if they are properly qualified to fly this plane.

Flip these two switches down, then fly the plane manually.

Why does everyone insist you need to rely on software to fly these planes?

BTW, this process is supposed to be committed to memory by pilots who are properly trained to fly these planes.

I earned that rank, dammit.

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I like Delenn’s advice.

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Reuters reports that the Lion Air pilots “scoured" the “checklist of abnormal events” in the quick reference manual as “the jet was lurching downward” from 5,000 feet for 9 minutes before crashing in October, killing all 189 aboard.

Reuters also reports that the same plane had similar flight control problems the night before the crash, but a 3rd pilot was able to “solve” the problem on that flight.

Then another 2 pilots appear to have faced similar issues and had similar results with the Ethiopian crash in March, killing another 157 passengers.

Only 1 pilot out of 7 was able to “solve” the problem, based on known events.

Not surprising, since the Seattle Times reports that “737 pilots were not informed about the implementation of MCAS [Maneuvering Characteristics Augmentation System] to their planes” and “information about MCAS was not added to their flight manuals”, and the MCAS problem “doesn’t look like a standard stabilizer runaway”.

Boeing now reportedly plans to update pilot training and flight crew manuals to include MCAS, upgrade planes that don’t already have a sensor-disagreement warning light, take input from two “angle of attack” sensors instead of just one, give MCAS less authority to override pilot commands and disable MCAS after 1 attempt to avert a stall (MCAS is reported to exist to counter “stall” tendencies due to “forward engine placement” of more powerful engines on this version of the 737).

  • Seattle Times, March 17, 2019, Flawed analysis, failed oversight: How Boeing, FAA certified the suspect 737 MAX flight control system

  • Reuters, March 20, 2019, Exclusive: Cockpit voice recorder of doomed Lion Air jet depicts pilots’ frantic search for fix

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The captain fought to climb, but the computer, still incorrectly sensing a stall, continued to push the nose down using the plane’s trim system. Normally, trim adjusts an aircraft’s control surfaces to ensure it flies straight and level.

The pilots are actively fighting the controls, counteracting plan A, so the computer goes to Plan B and buggers the trim. Hell, what was the computer’s plan C, eject the rear passengers to make the nose relatively heavier?

Murder most memo.

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these wheels are called the “stab trim” and the general idea is that once the aircraft is flying at the desired speed and attitude, the pilots may find that they need to apply force to the control column to maintain that attitude. by adjusting the stab trim they can, well, “trim” the controls until no more force on the control column is needed to maintain the attitude. it gets pretty tiring continuously applying force to the control column.

having said all that, on a modern jetliner really just the initial takeoff and landing phases are flown manually. during the rest of the time, the autopilot is used, and it handles all the control surfaces including the stab trim. as mikekstar says the trim wheels move in a boeing jet to serve as visual feedback that the computer is adjusting the stab trim.

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Interesting investigative reporting by the Seattle Times:

Equally interesting is the critical article by EE Times that writes:

In essence, these critics say, Boeing’s response to the challenge posed by Airbus was bumping passenger safety to a middle seat in economy class while financial considerations were upgraded to First Class.

https://www.eetimes.com/document.asp?doc_id=1334482

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extra software is required because the forward placement and height of the LEAP engines imparts a moment which can cause the plane to pitch up, putting it at risk of aerodynamic stall. boeing put in a new stab control routine that would automatically pitch the nose down in case the AoA became too high, so that the MAX “felt” the same to pilots as the prior 737s with CFM56 engines. this, because they didn’t want to have to get the airframe recertified but sucessfully lobbied the FAA to grandfather the MAX on the prior 737NG certification.

then, they didn’t tell anyone about that new stab control routine. 737 pilots are all trained for runaway stab trim, but since this system would kick in intermittently, each time incrementally moving the stabilizers up, pilots were not likely to recognize the situation as a runaway stab trim situation, where the trim wheels would move continuously. therefore they never thought to reach for the stab trim breakers. and 2 planes crashed.

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LOL I guess.

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As I understood it, there indeed was differential training for the MAX types, but nothing in it, or in any of the flight handbooks, checklists, or other crew documentation referenced MCAS?