Boeing Officially Issues Safety Warning for 737 MAX, FAA to Issue Airworthiness Directive

Boeing has officially issued a safety message to operators of all 200 of its 737 MAX aircraft in service, advising how to handle the plane in an instance when erroneous data from a key sensor comes about. The statement, which was first reported by Bloomberg from an anonymous source on Tuesday night, comes just more than one week after Lion Air Flight 610, a Boeing 737 MAX aircraft, crashed off the coast of Indonesia, killing all 189 people on board.

As part of Boeing’s statement, which was officially issued late Tuesday, the aircraft manufacturer said that the Indonesian National Transportation Safety Committee “indicated that the aircraft operating Flight 610 experienced erroneous input from one of its AOA (Angle of Attack) sensors.”

The AOA sensors are crucial in helping an aircraft’s system understand whether its nose is too high relative to the angle at which air passes over the wings. In the case of insufficient flow of air over the wings, the aircraft would not be able to generate enough lift to keep flying, resulting in a stall.

Boeing’s statement continued:

“Whenever appropriate, Boeing, as part of its usual processes, issues bulletins or makes recommendations regarding the operation of its aircraft.

On November 6, 2018, Boeing issued and Operations Manual Bulletin (OMB) directing operators to existing flight crew procedures to address circumstances where there is erroneous input from an AOA sensor.”

According to NBC News, the Boeing 737 MAX has three AOA sensors on the fuselage. It’s unclear how much time the crew of Lion Air Flight 610 had to react to the erroneous data from the sensor, as the aircraft was only a few thousand feet in the air.

In a statement, Boeing said that it’s “providing support and technical assistance to the Indonesian National Transportation Safety Committee and other government authorities responsible for the investigation into Lion Air Flight 610.”

On Wednesday, the Federal Aviation Administration said in a statement that it plans to issue an airworthiness directive, saying it “will take further appropriate actions depending on the results of the investigation.”

Norwegian Air, which operates 14 737 MAX 8 aircraft, said that all of its aircraft were functioning normally after receiving the service bulletin from Boeing, according to Reuters.

In the US, several airlines operate Boeing 737 MAX aircraft of different variants. These include American Airlines, Southwest Airlines and United Airlines. Alaska Airlines also has an order for 32 737 MAX 9s, which have yet to be delivered. Worldwide, the MAX — the latest evolution of the workhorse 737, featuring new engines — is in service with many other carriers, after being introduced in 2017.