More 737 educated speculation: Runaway Trim and pilot training

My dad just shared an email conversation he had with an aviation colleague. My dad also added that surprise “runway trim” situations were almost always included in his simulator training for 6-10-seat turboprops back in the 80s and 90s.

All bolding is mine:

I never flew the 737 but did fly the 727, 757, and 767. I just flew back to Atlanta last night from Phoenix on Southwest. Had a long talk with commuter F/O coming home about the B-737Max8. We were on a Southwest B-737-800, same airplane but smaller engines. Very knowledgeable guy, ASA pilot, and now Southwest.

The “problem” manifests itself as runaway trim. Easily stopped by turning off electric trim, except runaway trim is no longer a memory item. The F/O said the manual trim wheel spins just like it does with electric trim. I think the F/O said there are only four emergency memory items left. Aviation has been dumbed down too much. We used to get a runaway trim problem just about every simulation training ride.

The MCAS (Maneuvering Characteristics Augmentation System), which is, they think, causing the problem, is a modification Boeing thought necessary because of the placement and size of the new very fuel efficient engines. By the way, the same engine is on Delta’s A-321, according to this F/O. The engine is so big in diameter, Boeing had to extend the landing gear to raise the aircraft higher and move the placement of the engine on the wing from earlier B-737 versions. Now, when power is adjusted, the airplane pitches enough that Boeing thought it necessary for automatic trim, faster than normal autopilot trim. The MCAS is also tied into the stall warning and pushes the nose down. Stick shaker and verbal warnings are no longer enough for a stall warning.

Partial solution: bring back the memory item for runaway trim and trust an experienced western trained pilot to recognize the problem. It was reported the F/O on Ethiopian had just 200 hours. The minimum for a F/O in the U.S. is 1500 hours. Quality of training is also a major factor. And if the angle-of-attack gives false information, maybe give the crew some options before trying to take control of the airplane. (Wait a minute!- we already have that with stick shaker, etc.)

I would not hesitate to fly on one of American’s or Southwest’s Max8s. If any of you hear anything different, let me know.


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