Acting Federal Aviation Administration chief Daniel Elwell will tell a Senate hearing Wednesday that “Boeing submitted … to the FAA for certification” its proposed flight-control software enhancement for the 737 MAX 8 on Jan. 21, according to a copy of his prepared remarks obtained by the Seattle Times.
That’s nearly seven weeks before the fatal crash of Ethiopian Airlines Flight 302 that killed 157 people.
Elwell’s testimony says “the FAA’s ongoing review of this software installation and training is an agency priority.”
Yet the revelation that the agency had at least an early version of Boeing’s software patch in January is sure to raise the question of whether it could have been approved and deployed to the worldwide MAX fleet earlier, before the Ethiopian Airlines accident.
Boeing’s software update is intended to address flaws in a new flight-control system, called MCAS, for Maneuvering Characteristics Augmentation System, that Boeing introduced on the MAX 8. That system is suspected of causing the crash of Lion Air Flight 610 in October, in which 189 people died, with indications that it may also have played a role in the Ethiopian crash this month.
Clearly, great care must go into the assessment of any change to an airplane system to ensure it’s safe and doesn’t inadvertently cause new problems.
Elwell will testify that since January the FAA has been doing intensive testing of the updated Boeing system, according to his prepared remarks.
“To date, the FAA has tested this enhancement to the 737 MAX flight control system in both the simulator and the aircraft. The testing, which was conducted by FAA flight test engineers and flight test pilots, included aerodynamic stall situations and recovery procedures,” he’ll testify.
FAA spokesman Lynn Lunsford said that testing was done “with prototypes and early versions” of Boeing’s software update.
He said the safety agency is expecting to get only this week from Boeing “the service-ready product for evaluation.”
Boeing lays out its efforts to produce the fix
In a separate statement, a Boeing official outlined the company’s efforts to get the software update ready.
The official said that after developing the update, Boeing pilots used lab tests and simulator flights to evaluate it, testing a variety of scenarios and varying the angle of attack and airspeed to assess the effect on other systems in the airplane.
The official said the FAA participated in the evaluation, which was designed “to ensure that normal airmanship skills are sufficient to control the airplane.”
In the simulator, they tested “single and multiple errors or failures, subjecting the equipment to the most challenging scenarios,” the official said.
Then on Feb. 7, Boeing engineering conducted a verification test flight.
“Test pilots flew different maneuvers and flight conditions that exercised various aspects of the software update, checking normal operations and executing numerous conditions with induced failures,” Boeing said.
The scenarios tested included sustained flight with the angle of attack high for a long period of time; steep turn maneuvering; MCAS activation; and introduction of angle of attack errors.
Boeing’s test pilots next conducted a certification flight with the FAA on March 12, just a day before the agency ordered all MAX 8 commercial flights grounded.
After the proposed certification plan for the MCAS software update was submitted in January — the government shutdown ended just four days later — Boeing said it has throughout February and March kept the FAA informed of the testing and provided the documentation required to show compliance with FAA regulations.
The final submission to the FAA is expected at the end of this week, the Boeing official said.
New light on MCAS safety
Elwell’s statement to the Senate subcommittee on aviation also addresses the FAA’s original certification of the 737 MAX 8 in 2017, which as the Seattle Times reported has drawn criticism from some of the agency’s own technical staff for having delegated too much of the system evaluations to Boeing itself and providing FAA staff insufficient time for proper review of those evaluations.
In particular, the scrutiny of the new MCAS system during certification appears with hindsight to have been inadequate.
Yet Elwell will testify that “FAA engineers and flight test pilots were involved in the MCAS operational evaluation flight test. The certification process was detailed and thorough.”
However, he adds in his written testimony, “but, as is the case with newly certified products, time yields more data to be applied for continued analysis and improvement.”
“As we obtain pertinent information, identify potential risk, or learn of a system failure, we analyze it, we find ways to mitigate the risk, and we require operators to implement the mitigation,” Elwell’s testimony states. “That is what has happened in the case of the 737 MAX.”
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