Boeing knew about problems with 737 Max a year before Lion Air crash and did nothing about them

The feature was designed to warn pilots when a key sensor might be providing incorrect information about the pitch of the plane's nose.


                            Boeing knew about problems with 737 Max a year before Lion Air crash and did nothing about them

Boeing Co. had known before the deadly 737 Max crash in Indonesia that a cockpit safety alert wasn’t working the way the company had told the buyers of the jetliners. 

Now according to a Boeing statement on Sunday, they had not informed the airlines concerned or the Federal Aviation Administration of the problem with the warning light until after a Lion Air plane went down off the coast of Indonesia in October.

The safety feature was designed to warn pilots when a key sensor might be providing incorrect information about the pitch of the plane's nose.  The indicator was supposed to tell pilots when sensors that measure the pitch of the plane's nose appear to conflict, a sign that the sensor information is unreliable. Boeing told airlines that the warning light was standard equipment on all Max jets.  However, Boeing engineers quickly learned, that the warning light only worked if airlines also bought an optional gauge that told pilots how the plane's nose was aimed in relation to the onrushing air. Boeing said the problem stemmed from software delivered to the company.

Boeing said Sunday, May 5, 2019, that it discovered after airlines had been flying its 737 Max plane for several months that a safety alert in the cockpit was not working as intended, yet it didn't disclose that fact to airlines or federal regulators until after one of the planes crashed. (Source: AP Photo/Ted S. Warren, File)

The sensors malfunctioned during an October flight in Indonesia and another in March in Ethiopia, causing software on the plane to push the nose down. Pilots were unable to regain control of either plane, and both crashed, killing 346 people.

While there is no proof that the warning light would have prevented either the Lion Air crash or the March 10 crash of an Ethiopian Airlines Max near Addis Ababa. Boeing's disclosure on Sunday, however, raised fresh questions about the company's honesty with regulators and airline customers.

Boeing said again that the plane was safe to fly without the sensor alert, called an angle-of-attack disagree light. Other gauges tell pilots enough about the plane's speed, altitude, engine performance and other factors to fly safely, the company said. A spokesman for the Federal Aviation Administration said the agency was notified of the non-working warning light in November, after a Lion Air 737 Max crashed on October 29 in Indonesia. He said FAA experts determined that the non-working cockpit indicator presented a low risk.

The 737 MAX, Boeing's newest model, has been grounded by aviation authorities throughout the world after the crash of an Ethiopian Airlines 737 MAX 8 on March 10. (Source: Stephen Brashear/Getty Images)

"However, Boeing's timely or earlier communication with (airlines) would have helped to reduce or eliminate possible confusion," the spokesman said in an emailed statement. He declined to give more details.

Boeing said Sunday that because in-house experts decided that the non-working light didn't affect safety, the company decided to fix the problem by disconnecting the alert from the optional indicators at the next planned update of cockpit display software.

Boeing didn't tell airlines or the FAA about this decision.  Boeing hopes to win approval from the FAA and foreign regulators to get the Max flying again before summer is over. When it does, the company said, the sensor warning light will be standard.

- with inputs from AP