A faulty angle-of-attack sensor on a Boeing 737 MAX belonging to the Lion Air airline is linked to the cause of the jetliner’s crash in Indonesia on October 29 last year, the CFTS portal reports, citing the Vedomosti publication.

This is indicated in documents prepared for a briefing in the Indonesian parliament, which the Bloomberg news agency obtained.

Erroneous signals from that sensor triggered the repeated nose-down movements of the jetliner, which preceded the crash. The sensor itself was repaired at the XTRA Aerospace Inc. aircraft maintenance facility in Miramar (Florida) before the flight.

The repaired sensor was later installed on the Lion Air plane on October 28 after pilots had reported problems with instruments displaying speed and altitude. The Indonesian National Transportation Safety Committee is now seeking data from the repair facility in Florida. The sensor was made by Rosemount Aerospace Inc. (Minnesota), a subsidiary of United Technologies Corp.

Another Boeing 737 MAX belonging to Ethiopian Airlines crashed in Ethiopia under similar circumstances in March this year. There is no indication that the Florida facility did maintenance on the Ethiopian jetliner’s device angle-of-attack sensor.

Pilots at the controls of the Ethiopian Airlines’ Boeing 737 MAX that crashed in Ethiopia in March initially followed emergency procedures laid out by the plane maker but still failed to recover control of the jet, the Wall Street Journal reports, citing people briefed on the crash investigation’s preliminary findings. The pilots initially shut off the MCAS (Maneuvering Characteristics Augmentation System) anti-stall system that was pushing the airplane’s nose down shortly after it took off. The pilots then used a manual wheel in an attempt to stabilize the plane, but they eventually began to use electric switches to try to raise the plane’s nose. However, the electric power also reactivated MCAS, allowing it to continue its strong downward commands.

The two crashes involving the Boeing 737 MAX killed 346 people. According to estimates by Bloomberg Intelligence, Boeing may have to pay about USD 1 billion to settle the multiple wrongful-death lawsuits filed against it on behalf of victims of the Lion Air and Ethiopian Airlines plane crashes.

As the CFTS portal reported earlier, Norwegian Air is the first airline to announce that it will seek compensation from Boeing for costs and lost revenue after grounding its fleet of 737 MAX 8 aircraft in the wake of the Ethiopian Airlines crash.