Boeing has begun flight testing its grounded 737 Max after receiving approval from the Federal Aviation Administration (FAA) on Sunday.
The test flights are a key step in the troubled aircraft returning to service after being banned from the skies for more than a year.
The US’ aviation regulatory body said in an email to lawmakers that FAA and Boeing test pilots will evaluate the planemaker’s proposed changes to the MCAS automated flight control system, which was partly blamed for two fatal crashes which killed 346 people.
“Testing is expected to take several days, and will include a wide array of flight maneuvers and emergency procedures to enable the agency to assess whether the changes meet FAA certification standards,” the email said.
The FAA and Boeing crew are running through mid-air scenarios on-board a 737 Max 7 and intentionally triggering the updated MCAS system.
Boeing said earlier this year that it expected to have the 737 Max cleared for service by mid-2020 but the FAA has said multiple times that it refuses to be hurried into making a decision. The regulator told Congress on Sunday that it has not set a date for when the ban on the Max will be lifted.
The 737 Max crashes and subsequent delays getting the jet back to service represent the worst crisis in Boeing’s history. Boeing’s woes have been made worse by the Covid-19 pandemic, which has severely dented demand for new commercial aircraft.