Boeing Issues Safety Warning on 737 Max After Lion Air Crash

Boeing Issues Safety Warning on 737 Max After Lion Air Crash

"The Indonesian National Transportation Safety Committee has indicated that Lion Air flight 610 experienced erroneous input from one of its AOA (angle of attack) sensors", Boeing said in a statement on its website on Wednesday.

"Angle of attack" refers to the angle between relative wind and a reference line on the plane - the sensors' objective is to ensure that air flows over an aircraft's wings, Bloomberg reported.

Lion Air's first two attempts to address the airspeed problem didn't work, and for the jet's second-to-last flight the "angle of attack" sensors were replaced, Tjahjono said.

CNN said Indonesian officials are working with Boeing and safety experts to further investigate the airspeed indicator issue.

WestJet also has 9 of the 737 MAX jets in its fleet, but the airline did not immediately respond to a query about the Boeing bulletin from CBC News.

KNKT is planning to simulate a flight to assess the impact of sensor damage at Boeing's engineering simulator facility in Seattle.

But more importantly, the investigation-led by Indonesian authorities with the cooperation of Boeing and the U.S. National Transportation Safety Board-will determine what changes should happen to not only prevent the sensor failure from reoccurring, but hopefully also prevent such a failure from spiraling so horribly out of control even when it does happen.

A preliminary report on the cause of the accident is expected at the end of the month.

Boeing will caution its customers of "erroneous readings" from a flight-monitoring system can cause the planes to abruptly dive, Bloomberg quoted an anonymous source as saying. The "angle of attack" is the angle of the airplane or its wings compared with oncoming air or wind.

Safety investigators said that pilots on the plane were dealing with inaccurate airspeed readings and asked to return to the airport just before the crash. The angle of attack sensor replaced in Bali would be analyzed at its place of manufacture in Chicago, the accident investigator said.

Personnel from National Transportation Safety Board examine debris from Lion Air flight JT610 at Tanjung Priok port in Jakarta, Indonesia, on November 1, 2018.

Boeing said it is cooperating fully and providing technical assistance as the investigation continues.

According to Pramintohadi, the Boeing 737-900 ER aircraft was scheduled to depart for Soekarno-Hatta International Airport near Jakarta at 6:20 p.m. The system alerts pilots if it senses a possible malfunction.

Through September, Boeing has taken orders for 4,783 737 MAX aircraft with 219 delivered to customers.

"The bulletin reinforces existing procedures which all Air Canada crews are now trained on", Fitzpatrick said.

A winglet on the first Boeing 737 MAX airliner is pictured at the company's manufacturing plant in Renton, Washington, on December 8, 2015. "The tariffs are pushing Boeing to start local production", Bai said.