The Ethiopian Airlines plane that crashed last month nosedived several times before it hit the ground, a preliminary report has found.
The report says the flight’s pilots repeatedly followed procedures recommended by Boeing before the crash.
On March 10, Ethiopian Airlines flight ET 302 crashed shortly after take-off from Nairobi on its way to Addis Ababa with 149 passengers and eight crew members on board.
It was the second crash of a Boeing 737 Max aircraft in five months. Last October, Lion Air flight JT 610 crashed into the sea near Indonesia killing all 189 people on board.
Anti-stall software
The report notes that in the final seconds before the Ethiopian Airlines crash, pilots tried to right the plane by switching its anti-stall software on and off but this did not work. The plane hit an airspeed of 500 knots (575mph), well above its operational limits, before cockpit data recordings stopped.
Despite their efforts, pilots “were not able to control the aircraft”, Transport Minister Dagmawit Moges reportedly said.
The 737 Max family of aircraft was grounded following the Ethiopian Airlines crash, affecting over 300 planes.
Chain of events
Dennis Muilenburg, Chairman, President & CEO, Boeing, said the report made it apparent that “in both flights, the Maneuvering Characteristics Augmentation System, known as MCAS, activated in response to erroneous angle of attack information.”
He commented: “The history of our industry shows most accidents are caused by a chain of events. This again is the case here, and we know we can break one of those chain links in these two accidents. As pilots have told us, erroneous activation of the MCAS function can add to what is already a high workload environment. It’s our responsibility to eliminate this risk. We own it and we know how to do it.”
Boeing has developed a software update to the MCAS on the 737 MAX.
Muilenburg said: “We’re taking a comprehensive, disciplined approach, and taking the time, to get the software update right. We’re nearing completion and anticipate its certification and implementation on the 737 MAX fleet worldwide in the weeks ahead. We regret the impact the grounding has had on our airline customers and their passengers.
“This update, along with the associated training and additional educational materials that pilots want in the wake of these accidents, will eliminate the possibility of unintended MCAS activation and prevent an MCAS-related accident from ever happening again.”
“I cannot remember a more heart-wrenching time in my career with this great company,” Muilenburg said.
Muilenburg s said Boeing “remains confident in the fundamental safety of the 737 MAX.”
He added. “When the MAX returns to the skies with the software changes to the MCAS function, it will be among the safest airplanes ever to fly.”
