What Really Brought Down the Boeing 737 Max?

What Really Brought Down the Boeing 737 Max?
Malfunctions caused two deadly crashes. But an industry that puts unprepared pilots in the cockpit is just as guilty.
By William Langewiesche
Sep 18 2019
<https://www.nytimes.com/2019/09/18/magazine/boeing-737-max-crashes.html>

On Oct. 29, 2018, Lion Air Flight 610 taxied toward the runway at the main airport in Jakarta, Indonesia, carrying 189 people bound for Bangka Island, a short flight away. The airplane was the latest version of the Boeing 737, a gleaming new 737 Max that was delivered merely three months before. The captain was a 31-year-old Indian named Bhavye Suneja, who did his initial flight training at a small and now-defunct school in San Carlos, Calif., and opted for an entry-level job with Lion Air in 2011. Lion Air is an aggressive airline that dominates the rapidly expanding Indonesian market in low-cost air travel and is one of Boeing’s largest customers worldwide. It is known for hiring inexperienced pilots — most of them recent graduates of its own academy — and for paying them little and working them hard. Pilots like Suneja who come from the outside typically sign on in the hope of building hours and moving on to a better job. Lion Air gave him some simulator time and a uniform, put him into the co-pilot’s seat of a 737 and then made him a captain sooner than a more conventional airline would have. Nonetheless, by last Oct. 29, Suneja had accumulated 6,028 hours and 45 minutes of flight time, so he was no longer a neophyte. On the coming run, it would be his turn to do the flying.

His co-pilot was an Indonesian 10 years his elder who went by the single name Harvino and had nearly the same flight experience. On this leg, he would handle the radio communications. No reference has been made to Harvino’s initial flight training. He had accumulated about 900 hours of flight time when he was hired by Lion Air. Like thousands of new pilots now meeting the demands for crews — especially those in developing countries with rapid airline growth — his experience with flying was scripted, bounded by checklists and cockpit mandates and dependent on autopilots. He had some rote knowledge of cockpit procedures as handed down from the big manufacturers, but he was weak in an essential quality known as airmanship. Sadly, his captain turned out to be weak in it, too.

“Airmanship” is an anachronistic word, but it is applied without prejudice to women as well as men. Its full meaning is difficult to convey. It includes a visceral sense of navigation, an operational understanding of weather and weather information, the ability to form mental maps of traffic flows, fluency in the nuance of radio communications and, especially, a deep appreciation for the interplay between energy, inertia and wings. Airplanes are living things. The best pilots do not sit in cockpits so much as strap them on. The United States Navy manages to instill a sense of this in its fledgling fighter pilots by ramming them through rigorous classroom instruction and then requiring them to fly at bank angles without limits, including upside down. The same cannot be expected of airline pilots who never fly solo and whose entire experience consists of catering to passengers who flinch in mild turbulence, refer to “air pockets” in cocktail conversation and think they are near death if bank angles exceed 30 degrees. The problem exists for many American and European pilots, too. Unless they make extraordinary efforts — for instance, going out to fly aerobatics, fly sailplanes or wander among the airstrips of backcountry Idaho — they may never develop true airmanship no matter the length of their careers. The worst of them are intimidated by their airplanes and remain so until they retire or die. It is unfortunate that those who die in cockpits tend to take their passengers with them.

It was a blue-sky morning in Jakarta, with a few clouds floating offshore to the north. The flight was assigned a standard departure route over the Java Sea. At 6:20 a.m., it was cleared for takeoff. To anyone observing the airplane externally, for instance from the control tower, the takeoff would have appeared ordinary as the Boeing lumbered down the runway and lifted into the air. The first external hint of trouble came about a minute later, after a departure controller cleared the flight for a climb to 27,000 feet. Harvino asked the controller to confirm the airplane’s current altitude as shown on the controller’s display. The request was unusual, and it went unexplained. The controller answered that he showed the altitude as 900 feet, and Harvino acknowledged him without comment as if he concurred.

Twenty-five seconds later (a long interlude in flight), Harvino requested a clearance to “some holding point” where the airplane could linger in the sky. The request was surprising. The controller did not provide a holding point but asked about the nature of the problem. Harvino answered, “Flight-control problem.” He did not mention which kind, but before they die, pilots are rarely so descriptive. Harvino did not declare an emergency. The controller asked about their intended altitude. Harvino answered 5,000 feet, which was strangely low and to this day remains unexplained.

Two and a half minutes after takeoff, as the airplane was climbing through 2,175 feet, it suddenly went into a violent 700-foot dive, rounding out of it at 1,475 feet and pulling into an uncertain climb. No turn was associated with the plunge, so the airplane’s problem seemed to be unrelated to roll control and the age-old menace of a spiral dive. Right from the start of the investigation, suspicions focused on Lion Air 610’s trim mechanism — and specifically on the possibility of a failure known as a runaway trim. Trim refers to an aerodynamic condition related to pitch — the nose-up-or-down attitude of an airplane in flight. It can be thought of as a balance point, or the nose attitude at which an airplane naturally rides when no up-or-down elevator-control deflections are applied. That is a slight simplification, but good enough. Trim is routinely adjusted in flight. In the Boeing 737, the adjustments are made by the use of thumb switches on the control wheels when the pilots are “hand flying” the airplane manually, as they would on takeoff and landing. The thumb switches control an electrohydraulic mechanism that changes the angle of the horizontal stabilizer — the all-important tail surface that counteracts the natural pitching effects of the wings and provides the necessary aerodynamic balance for flight. In its functioning, the electric trim is smooth, powerful and usually well behaved. On occasion, however, it may start running on its own volition and prompt the airplane to nose up or down. That’s a runaway trim. Such failures are easily countered by the pilot — first by using the control column to give opposing elevator, then by flipping a couple of switches to shut off the electrics before reverting to a perfectly capable parallel system of manual trim. But it seemed that for some reason, the Lion Air crew might not have resorted to the simple solution.

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