Following the crash of the Indonesia new Lion Air jetliner that crashed into the Java Sea killing all 189 people on board, Boeing is now reporting that a crucial sensor that is the subject of a Boeing safety bulletin was replaced in that aircraft the day before and possibly worsened other problems with the plane, Indonesian investigators said Wednesday (Nov. 7, 2018). The Federal Aviation Administration (FAA) is developing an Airworthiness Directive to require implementation of Boeing’s service bulletin regarding these aircraft.
The part is an “angle of attack” sensor that keeps track of the angle of the aircraft nose relative to oncoming air to prevent the plane from stalling and diving. A Boeing statement said today a safety bulletin sent to airlines yesterday directs flight crews to existing guidelines on how flight crews should respond to erroneous “angle of attack” data. It wasn’t immediately clear if the Chicago-based aircraft manufacturer plans an update, though comments from Indonesian officials indicated they expect one
Soerjanto Tjahjono, Chairman of Indonesia’s National Transportation Safety Committee, said today that airspeed indicator malfunctions on the jet’s last four flights, revealed by an analysis of the flight data recorder, were intertwined with the sensor issue. “The point is that after the AOA (sensor) is replaced the problem is not solved but the problem might even increase. Is this fatal? NTSC wants to explore this,” he said to the press.
CNN is reporting that this part malfunctioned for the first four flights of that particular aircraft. On the Boeing 737 MAX 8 plane’s second to last flight on Oct. 28, the angle of attack sensors were replaced, Tjahjono told the media.
On that flight, from Bali to Jakarta, the pilot’s and copilot’s sensors reportedly did not agree. The two-month-old plane went into a sudden dive minutes after takeoff, from which the pilots were able to recover. They decided to fly on to Jakarta at a lower than normal altitude. The next flight the following day on Oct. 29 led to the tragic crash of the jet. The plane hit the water at very high speed just 13 minutes after takeoff from Jakarta. Its flight crew had requested permission to return to the airport several minutes after taking off.
Investigators are still looking for the cockpit voice recorder, but the plane’s other black box, the flight data recorder, was located Thursday, and investigators said it showed Flight 610 had performed 19 flights — including its final flight.
Indonesia’s search and rescue agency has extended the search effort for a second time, saying it will continue until Sunday. Human remains reportedly are still being recovered by searchers.
The Lion Air crash is the worst airline disaster in Indonesia since 1997, when 234 people died on a Garuda flight near Medan. In December 2014, an AirAsia flight from Surabaya to Singapore plunged into the sea, killing all 162 on board.
The Lion Air crash raises the question whether this issue has been visited before with Boeing aircraft, in particular the crash of Turkish Airlines Flight 1951 that crash landed at Amsterdam Schiphol Airport on Feb. 25, 2009. That tragedy resulted in the death of nine passengers and crew, including all three pilots. Preliminary reports from the Dutch accident investigators suggested that a malfunctioning radio altimeter may have led the flight control system to automatically command a reduction in thrust, as well as a significant drop in airspeed and altitude, during final approach.
Clifford Law Offices represented more than a dozen individuals who were injured in that crash. The cases settled for confidential amounts.