Thirty-two hours after an Ethiopian Airlines 737 Max crashed on takeoff from Addis Ababa, killing all 157 aboard, shares of the plane’s manufacturer, Boeing, traced a similar trajectory, dropping 12 percent at the opening bell of the New York Stock Exchange and never fully recovering.
While the cause of the Ethiopian incident hasn’t yet been established, it makes sense that investors would lose confidence in Boeing: The crash came just five months after another involving a 737 Max in Indonesia, Lion Air Flight 610, and the dual disasters have spooked airlines and the traveling public. Erring on the side of caution, China and Indonesia have grounded the 737 Max, and 25 individual carriers have done so as well, including Ethiopian and Cayman Airways.*
The 737 Max first flew just two years ago, and some 350 are now in service. For such a new type of aircraft to suffer two fatal crashes is extraordinarily unusual, and bad. While the investigation into the Lion Air crash is still underway, a preliminary report suggests that the pilots failed to respond correctly after a faulty sensor led the autopilot to put the plane into a steep dive. We know even less about what happened to the Ethiopian flight. But no matter the causes, the mere fact that a single type of aircraft has had two accidents in swift succession raises questions about the trustworthiness of its manufacturer. Boeing has heretofore enjoyed a sterling reputation; its most recent all-new design, the 787, has never had a fatality, and the one before that, the 777, went 18 years without one. So it’s worth asking: How did Boeing find itself suddenly in this reputational shitstorm?
It all comes down to business strategy. Chicago-based Boeing is locked in a fierce duopolistic rivalry with Toulouse, France–based Airbus, with whom it roughly splits the $200 billion airliner market. The biggest segment of that market is for short- to medium-range narrow-body jets that typically carry between 100 and 200 passengers. These are the workhorses of aviation, unglamorous and hard-ridden, endlessly bouncing back and forth on routes like Salt Lake–Denver and La Guardia–O’Hare.
Boeing’s entry, the 737, first flew in 1967, and though various improvements have been rolled out over the years, at heart it’s still a creature of the Right Stuff era. Instead of computer-controlled fly-by-wire controls, which guide a plane’s flight electronically, it still has old-fashioned mechanical actuators, and it’s made of aluminum rather than modern lightweight composites.
Airbus’ A320 family, meanwhile, took to the skies a generation later, in 1987, but it was a fly-by-wire, composite creature from the get-go. In 2014, Airbus rolled out its most recent iteration, the A320neo, a range of jets with engines that were billed as being 15 percent more fuel efficient than the old model.
To maintain its lead, Boeing had to counter Airbus’ move. It had two options: either clear off the drafting tables and start working on a clean-sheet design, or keep the legacy 737 and polish it. The former would cost a vast amount—its last brand-new design, the 787, cost $32 billion to develop—and it would require airlines to retrain flight crews and maintenance personnel.
Instead, it took the second and more economical route and upgraded the previous iteration. Boeing swapped out the engines for new models, which, together with airframe tweaks, promised a 20 percent increase in fuel efficiency. In order to accommodate the engine’s larger diameter, Boeing engineers had to move the point where the engine attaches to the wing.* This, in turn, affected the way the plane handled. Most alarmingly, it left the plane with a tendency to pitch up, which could result in a dangerous aerodynamic stall. To prevent this, Boeing added a new autopilot system that would pitch the nose down if it looked like it was getting too high. According to a preliminary report, it was this system that apparently led to the Lion Air crash.
If Boeing had designed a new plane from scratch, it wouldn’t have had to resort to this kind of kludge. It could have designed the airframe for the engines so that the pitch-up tendency did not exist. As it was, its engineers used automation to paper over the aircraft’s flaws. Automated systems can go a long way toward preventing the sorts of accidents that arise from human fecklessness or inattention, but they inherently add to a system’s complexity. When they go wrong, they can act in ways that are surprising to an unprepared pilot. That can be dangerous, especially in high-stress, novel situations. Air France 447 was lost in 2009 after pilots overreacted to minor malfunctions and became confused about what to expect from the autopilot.
In the wake of crashes like last weekend’s, there are always calls for improved training and awareness, and that undoubtedly helps. But it can only go so far. The human brain is fundamentally ill-equipped to work through unfamiliar problems when under high stress. Five years after AF 447, every Airbus pilot should have been hyperaware of how the pilots erred in that case, yet in 2014, the pilots of Air Asia 8501 did almost exactly the same thing, with the same result.
Do I know this is what happened with the Ethiopian Air flight? No. But regardless of how the investigation into that crash pans out, the 737 Max will look snakebit. An obvious analogy is Malaysia Airlines, which the public viewed with misgivings after it lost two 777s in less than five months in 2014. Though it bore no obvious responsibility for either incident—one was shot down by Russia; the second, MH370, is still a mystery, but as I argue in my book, the evidence indicates it was diverted by someone aboard the plane—the airline suffered a steep drop in bookings and went into reorganization the following year.*
Boeing isn’t facing that kind of financial disaster. The company is too big and too important to global aviation to fail. But the future of the 737 Max is suddenly looking shaky. No one has to buy that particular model when there are others on the market. Boeing’s either going to have to come up with a very convincing fix for whatever caused these two crashes, or think about starting over with a fresh sheet of paper.
Update, March 12, 2019: After the FAA announced Monday that it would require “design changes” to the 737 Max, Boeing confirmed that it would update the plane’s flight control software “across the 737 Max fleet in the coming weeks.”
Correction, March 12, 2019: An earlier version of this piece misstated that MH370 was hijacked, but there has been no official cause given for the disappearance of this flight.
Correction, March 19, 2019: This piece originally misstated that in order to make room for the bigger engine in the 737 Max, Boeing engineers moved the point where the airplane attaches to the wing. They moved the point where the engine attaches to the wing.
Update, March 12, 2019: The number of carriers that have grounded the 737 Max has increased since this article was published.
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