The fatal Lion Air crash has revved up debate about the biggest quandary in airline safety: how best to meld increasingly sophisticated computer controls, designed to prevent tragedies, with traditional piloting skills.
Ever-more-powerful cockpit automation and ultrareliable jet engines have contributed to record-low accident rates in recent years. For example, in 2017, there were fewer than three major accidents per one million commercial flights globally, and not a single scheduled jet airliner went down.
But the accident this past October involving Lion Air Flight 610, which killed 189 people in Indonesia, dramatically highlighted the hazards when automated flight-control features fail or misfire, and pilots aren’t able to respond properly.
The crash of the new Boeing 737 MAX 8 plane contributed to an erosion of the industry’s safety record last year—though it was still the third safest in terms of total airliner crashes. It amplifies the pressure on airplane makers like Airbus SE and Boeing Co. to calibrate the right mix of computer automation and pilot control.
“The industry must figure out new ways to effectively develop flying skills and enhance training so pilots can better respond to emergencies,” said consultant William Voss, a former U.S. and international safety official who also served as president of the nonprofit Flight Safety Foundation.
From takeoff to landing in virtually zero visibility, computers can operate the plane’s key systems. Pilots are supposed to monitor them and prepare for anything unexpected, typically spending only a few minutes per trip manually flying the plane.
During the 11-minute flight, the Lion Air pilots struggled to counteract a new stall-prevention system that repeatedly pushed down the plane’s nose due to erroneous sensor signals likely stemming from a maintenance lapse. The Boeing 737 MAX aircraft, which investigators believe wasn’t actually in danger of stalling, plunged into the Java Sea.
Following the accident, U.S. and European aviation regulators have been exchanging data about sensor failures leading to severe automation problems.
Patrick Ky, executive director of the European Aviation Safety Agency, said information exchanged with the U.S. Federal Aviation Administration focuses on how powerful automation systems should be able to cope with inaccurate sensor signals. “We have very automated machines,” he said. “But if something goes wrong, how do you allow the pilot to take over?”
Aircraft designers and training experts are considering how to ensure that future generations of pilots—steeped in touch-screen technology featuring supposedly infallible software—retain essential hand-flying and decision-making skills historically prized by the industry.
Adding to that challenge, Boeing estimates a global need for more than 750,000 new commercial pilots over the next two decades with substantially fewer hires coming from the military than before, resulting in generally lower experience levels.
Industry experts say enhanced cockpit automation is essential to produce aircraft geared toward even those pilots with only rudimentary skills, sometimes described as “least-common-denominator” crews. Above all, they say today’s jetliners and training programs are supposed to ensure all pilots, regardless of background, adhere to common safety practices.
However, some experts see this drive toward predictability producing highly scripted pilot training that doesn’t prepare aviators for rare dangers that can be bewildering. Because planes effectively fly themselves for long periods, pilots can become lulled into losing awareness of system functions.
But when displays show a torrent of fault messages accompanied by a cacophony of warning sounds, crews can become overwhelmed trying to simultaneously control the plane and manage the automation that is supposed to be in charge, said Mike Doiron, president of the consulting firm Cirrus Aviation Safety Services.
Roots of this automation dilemma stretch back nearly three decades, to when European plane maker Airbus first devised so-called fly-by-wire automated protections to prevent accidents. No matter what commands pilots give, under normal circumstances, computers on board won’t let them turn a plane too sharply or raise the nose to a dangerously high angle. Since then, Airbus has embraced more computer-driven safeguards, from automated midair collision-avoidance maneuvers to digital helpers alerting landing pilots about inadequate stopping distance.
Boeing, in contrast, has focused more on giving crews ultimate power to override almost any automated protections without disabling underlying systems. Regarding automation on 737 MAX models, Boeing has said it relied on its usual process to include all the information pilots need to safely operate the jets. After the crash, Chief Executive Dennis Muilenburg has said the planes don’t represent any change to the company’s design philosophy.
But in recent years, the two rivals have moved closer to each other with regard to cockpit automation.
Airbus, for example, has devised training programs for its A350 long-range models calling for pilots to get accustomed to the manual feel of the plane’s controls in initial simulator sessions, before activating normal automated systems.
Senior Airbus safety officials, who years ago argued it was their duty to install the most automation feasible on every new model, now say they spend more time worrying about potential unintended consequences of such decisions.
Boeing, for its part, has devised a host of advanced automated systems to take over if pilots or equipment err. If an engine fails on one of the company’s 777 jetliners at the moment of takeoff—generally considered the riskiest part of any plane trip—computers are designed to handle everything. They can adjust thrust on the remaining engine, move the rudder and initiate a smooth climb away from danger without any human input.
In the future, Boeing may embrace certain semiautonomous operations and artificial intelligence to prevent accidents. But Greg Hyslop, the company’s chief technical officer, pointedly asked at an aviation conference earlier this year in Seattle: “How do I certify that as safe?”
Airlines in the U.S., Europe and other mature aviation markets have urged pilots to spend more time manually flying aircraft as a way to prevent overreliance on automation. The aim is to enable crews to react more quickly and confidently when startled.
But such recommendations aren’t realistic for many fast-growing carriers in Asia and elsewhere scrambling to find enough fresh hires to fill crew rosters. “These pilots may lack the confidence to manually fly the aircraft,” said Cirrus Aviation’s Mr. Doiron.
Annemarie Landman, who has conducted research on pilot reaction for the Dutch research institute TNO, sees the growing complexity of automation itself as a huge hurdle. “When something goes wrong,” she said, “things get very confusing.”