
Photo: Stephen Brashear/Getty Images
Boeing is facing intense scrutiny for failing to provide instructions on how to operate a new automated flight-control system in the operations’ manual for its 737 MAX aircraft, a decision investigators say might have led to October's Lion Air crash that killed all 189 people on board off the coast of Indonesia.
Why it matters: As the Wall Street Journal notes in a detailed report published Wednesday, the move to “omit the control system from manuals has put a Boeing design principle at the center of a probe into a fatal airliner crash for the first time in more than two decades.” Questions about the crash have also threatened “to tarnish Boeing’s reputation for safety and its tradition of prioritizing pilot authority over automation.”
The bottom line: There’s reportedly an intense ongoing debate over the amount of training pilots should receive before they can safely go behind the controls of a Boeing 737 MAX.
What they're saying: A Boeing spokesperson told WSJ that the company did not deliberately keep information regarding how to operate the 737 MAX's control system away from aviators, and that officials have discussed the new system at industry conferences in recent years.
- “When Boeing developed its training and materials, it followed a process that was absolutely consistent with introducing previous new airplanes” and new models, the spokesperson said.
But regulators and pilots are questioning why Boeing failed to explain how the new system operates and why pilots weren’t trained on the specifies. “Key aspects of the system differ markedly from systems on the plane’s older versions,” WSJ notes.
- “Airline pilots need to know everything they can know about how the airplane works,” Gordon Bethune, a former Boeing executive who later served as the CEO of Continental Airlines, told WSJ. “The ball was dropped.”
The backdrop: Preliminary findings of the Lion Air investigation have focused on an erroneous input from one of the plane's angle of attack indicators. The indicators feed instruments and pilots information about whether the nose is pointed up or down, and by how much.
- Erroneous readings could cause the plane's computers to detect an impending stall, or loss of lift, and force the nose down repeatedly, overriding the pilot's inputs.
- This is apparently what happened in October's crash, when the plane eventually rapidly nosedived into the sea.
- According to a preliminary report of the crash, outline by WSJ: [T]he plane’s flight-control alerts malfunctioned ... providing erroneous stall-warnings from the instant it lifted off the runway. Cockpit instruments displayed a barrage of fault warnings, including unreliable airspeed and altitude, according to the report. The crew battled more than two dozen repeated automated nose-down commands by manually commanding nose-up maneuvers, until they lost control some 11 minutes after takeoff."
Yes, but: The overall safety of the 737 MAX isn't being questioned, WSJ notes. American Airlines, Southwest and United Continental Holdings — three of Boeing’s biggest 737 MAX customers — reportedly said their pilots are well-trained to fly the planes they said are safe.
- Meanwhile, Lion Air’s co-founder said the airline may cancel more than 200 orders for Boeing planes.
State of play: "The FAA confirmed it is reviewing its decision to accept Boeing’s initial risk analyses of the automated system and other approved systems on the new plane," per WSJ. "The FAA and Boeing also are developing a test of the entire MCAS system, which wasn’t previously required"