Two Boeing 737 Max crashes that killed all 346 passengers and crew aboard were the "horrific culmination" of failures by the plane maker and Federal Aviation Administration (FAA), a US House panel concluded after an 18-month investigation.
The crashes "were not the result of a singular failure, technical mistake, or mismanaged event", the House Transportation and Infrastructure Committee's Democratic majority said in its highly critical report released yesterday.
"They were the horrific culmination of a series of faulty technical assumptions by Boeing's engineers, a lack of transparency on the part of Boeing's management, and grossly insufficient oversight by the FAA."
The 737 Max was grounded in March the previous year after the crash of Ethiopian Airlines Flight 302 near Addis Ababa, killing all 157 aboard.
In October 2018, a Lion Air 737 Max had crashed in Indonesia, killing all 189 on board.
"Boeing failed in its design and development of the Max, and the FAA failed in its oversight of Boeing and its certification of the aircraft," the report said, detailing a series of problems in the plane's design and the FAA's approval of it.
Boeing said it "learned several hard lessons as a company from the accidents... and from the mistakes we've made".
It said it had cooperated fully with the House committee and that revised design work on the 737 Max had received intensive internal and external review involving more than 375,000 engineering and testing hours and 1,300 test flights.
The FAA said in a statement that it would work with legislators "to implement improvements identified in its report".
It added that it was "focused on advancing overall aviation safety by improving our organization, processes and culture".
The report said Boeing made "faulty design and performance assumptions", especially regarding a key safety system called MCAS, which was linked to both the Lion Air and Ethiopian Airlines crashes.
MCAS, which was designed to help counter a tendency of the Max to pitch up, could be activated after data from only a single sensor.
The FAA is requiring new safeguards to MCAS, including requiring it to receive data from two sensors, before it allows the 737 Max to return to service.
The report criticised Boeing for withholding "crucial information from the FAA, its customers and 737 Max pilots", including "concealing the very existence of MCAS from 737 Max pilots".
The FAA "failed to ensure the safety of the travelling public", the report said.
Legislators have proposed numerous reforms to restructure how the FAA oversees aircraft certification. A Senate committee was set to take up a reform Bill yesterday.
SERIES OF FAILURES
Boeing failed in its design and development of the Max, and the FAA failed in its oversight of Boeing and its certification of the aircraft.
THE U.S. HOUSE TRANSPORTATION AND INFRASTRUCTURE COMMITTEE, in a report on both Boeing 737 Max crashes.
Legislators suggested Boeing was motivated to cut costs and move quickly to get the 737 Max to market.
"This is a tragedy that never should have happened," House Transportation Committee chairman Peter DeFazio told newsmen.
"We're going to take steps in our legislation to see that it never happens again as we reform the system."
While Mr DeFazio and other legislators have not called for a permanent grounding of the jet, the father of a woman who died in the Ethiopia crash said the report raised questions concerning the plane's return to service.
"The FAA should immediately halt the recertification process for the 737 Max in light of this report," said Mr Michael Stumo, the father of Ms Samya Stumo.
He accused Boeing and the FAA of withholding information from the families of victims in an e-mailed statement.
REUTERS, BLOOMBERG