Technicalities: The Story Behind the Boeing 737 Max Grounding

Whom should we blame for the 737 Max debacle?

The cover story in The New York Times magazine for September 22, 2019, was entitled, “What Really Brought Down the Boeing 737 Max?” The writer, William Langewiesche—son of the sainted author of Stick and Rudder, Wolfgang Langewiesche—is a veteran of Flying, an experienced pilot, and a thorough and technically savvy researcher of his wide-ranging articles and books. As you can imagine, I read it eagerly.

The article had been posted online a couple of days earlier. By the time I checked, it had garnered more than 1,500 comments. I didn’t read all of them, but the reactions I saw seemed about equally divided between friendly and hostile.

I wrote a letter to the editor myself; it was not published. Despite the variety of online reactions, however, the letters to the editor that did appear two weeks later were, surprisingly, all favorable. Did the editors consider the critical reactions not worth printing?

In a nutshell, Langewiesche’s position was that the real reason for the two crashes—one in Indonesia and one in Ethiopia—that had cost hundreds of lives and led to the worldwide grounding of the airplane was the poor airmanship of the crews involved. Properly trained crews, he argued, should have been able to disable their misbehaving stability-augmentation systems—the now infamous MCAS—in the same simple way one would remedy a trim runaway. This is what Boeing apparently hoped any pilot would do in the event that the system, which applied nose-down trim more rapidly than the normal trim system would, went off when it shouldn’t.

Langewiesche documented in great detail the combination of corruption, greed and irresponsibility he said leads to the rapidly growing airlines of developing countries—notably, in this case, Indonesia’s Lion Air—putting novices fresh out of simulators into the cockpits of their jets. What these crews lacked, he argued, was the wide experience in airplanes and flight operations of all sorts that enables pilots to react calmly and resourcefully to unfamiliar situations. Using cockpit voice and flight-data records, he dissected second by second the reactions of the two crews to the pitch-downs that had been triggered in each case by a single faulty angle of attack sensor. He showed how all four pilots failed to cope appropriately—one of them, in fact, turning to prayer as a last, and futile, resort.

Many online commenters branded the argument racist. It may have sounded that way, but I think, if Langewiesche was swayed by any unconscious prejudice, it was by a sort of class feeling: the belief of an experienced pilot—who has logged many hours flying freight in junky airplanes and seen a thing or two—that old-timers like himself are real pilots, and relative newbies simply aren’t there yet.

The refrain that young pilots “don’t know how to fly” is not infrequently heard from senior and retired captains. If it’s true, it’s not entirely surprising; just learning systems and procedures takes all of a new pilot’s training time. The design philosophy underlying the Airbus fly-by-wire system—in which the airplane, not the pilot, has the final say—signals tacit acceptance of this situation. Airbus airplanes are not so much flown as managed. You tell the airplane’s computers what you want; they do the actual flying. Software guardrails protect the airplane from clueless pilots. Many American pilots, even those flying Airbus equipment, have professed to prefer the Boeing philosophy, in which the pilot can override the airplane rather than vice versa. Boeing airplanes, they said, were “pilots’ airplanes,” and Boeing pilots were real pilots.

Read More from Peter Garrison: Technicalities

By now, no one can be unaware that the MCAS design was flawed. It was originally added to deal with changes in the 737’s longitudinal stability caused by the more forward position of new, larger engines on the low-slung jet. Boeing management deliberately minimized its importance, almost to the point of concealment, in order to hurry the new model into service without its requiring recertification or pilot retraining. Regulators—mainly the FAA, lulled by decades of reliance on Boeing’s competence and honesty—had not caught on.

Langewiesche conceded that Boeing had made mistakes but passed lightly over them, expressing little more than mild puzzlement over the company’s actions. I thought it would have been interesting to know as much about conversations that may have taken place in Boeing’s engineering and flight-test spaces as we know about what happened in the cockpits of the doomed airplanes. It’s hard to imagine that no one questioned the wisdom of allowing this powerful, fast-acting system to be triggered by an additional faulty sensor.

Three weeks after the article appeared, The New York Times printed a single belated letter. It was from Chesley Sullenberger.

Sullenberger, whose successful ditching of a goose-disabled Airbus in the Hudson River in New York has elevated him into a sort of Lindbergh for our time, was one of the pilots invited to reenact the accidents on a full-motion simulator. He dismissed as an “age-old aviation canard” Langewiesche’s idea that the pilots’ airmanship, or lack of it, was to blame, though he agreed with him that “inadequate pilot training and insufficient pilot experience are problems worldwide.” Still, Sullenberger wrote, “they do not excuse the fatally flawed design [of the] pernicious and deadly” MCAS, a “death trap” that never should been approved, by neither Boeing nor the FAA. “Boeing made faulty assumptions,” he said, not only about the reliability of the system itself but also about “the level of human performance possible once the failures began to cascade.” Inappropriate MCAS activations “did not present as a classic runaway stabilizer problem.” The airplanes felt and behaved differently than they would have with runaway trim, and crews might therefore look elsewhere for the cause, which Boeing had gone out of its way to hide.

Having more than once, in 50 years of flying, looked back with disbelief and embarrassment at my own reactions to in-flight emergencies and anomalies, I empathize with anyone who doesn’t reason accurately when failures begin to “cascade.” My own reaction to the article was in some ways similar to Sullenberger’s. My letter to The Times said, in part: “I have written an airplane-accident-analysis column for Flying magazine for many years, and something I have learned is that no pilot or crew can be certain of their reaction to an unexpected emergency. If Langewiesche struggles to define the quality of ‘airmanship’ that the accident crews supposedly lacked, it is because airmanship exists only after the fact. It knows no national boundaries. You can never tell who has the presence of mind to cope with unexpected and frightening events until the crisis is over. Because human performance is unpredictable, it is the duty of airplane manufacturers to provide crews with every possible advantage for coping with the unexpected. Boeing didn’t.”


This story appeared in the Jan/Feb 2020 issue of Flying Magazine

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