In the brutally competitive jetliner business, the announcement in late 2010 that Airbus would introduce a more fuel-efficient version of its best-selling A320 amounted to a frontal assault on its archrival Boeing’s workhorse 737.
Boeing scrambled to counterpunch. Within months, it came up with a plan for an upgrade of its own, the 737 Max, featuring engines that would yield similar fuel savings. And in the years that followed, Boeing pushed not just to design and build the new plane, but to persuade its airline customers and, crucially, the Federal Aviation Administration, that the new model would fly safely and handle enough like the existing model that 737 pilots would not have to undergo costly retraining.
Boeing’s strategy set off a cascading series of engineering, business and regulatory decisions that years later would leave the company facing difficult questions about the crash in October of a Lion Air 737 Max off Indonesia.
The causes of the crash, which killed 189 people, are still under investigation. Indonesian authorities are studying the cockpit voice recorder for insights into how the pilots handled the emergency, and are examining Lion Air’s long history of maintenance problems.
But the tragedy has become a focus of intense interest and debate in aviation circles because of another factor: the determination by Boeing and the F.A.A. that pilots did not need to be informed about a change introduced to the 737’s flight control system for the Max, some software coding intended to automatically offset the risk that the size and location of the new engines could lead the aircraft to stall under certain conditions.
That judgment by Boeing and its regulator was at least in part a result of the company’s drive to minimize the costs of pilot retraining. And it appears to have left the Lion Air crew without a full understanding of how to address a malfunction that seems to have contributed to the crash: faulty data erroneously indicating that the plane was flying at a dangerous angle, leading the flight control system to repeatedly push the plane’s nose down.
Understanding how the pilots could have been left largely uninformed leads back to choices made by Boeing as it developed the 737 Max more than seven years ago, according to statements from Boeing and interviews with engineers, former Boeing employees, pilots, regulators and congressional aides.
Those decisions ultimately prompted the company, regulators and airlines to conclude that training or briefing pilots on the change to the flight control system was unnecessary for carrying out well-established emergency procedures.
The story of the change to that system, and how it came to play a central role in the Lion Air crash, shows how safety on modern jetliners is shaped by a complex combination of factors, including fierce industry competition, technological advances and pilot training. It illustrates how, in the rare instances when things go awry, the interplay of those factors can create unintended and potentially fatal consequences.