Boeing is to begin safety test flights for the 737 Max after getting clearance from the Federal Aviation Administration.
According to reports, test flights could begin as early as today near Boeing’s manufacturing base at Seattle.
The BBC says pilots and technical experts from regulators and the company are understood to be planning three days of safety tests on the 737 Max, which was taken out of service in March 2019, following two crashes in which 349 people died.
The FAA confirmed on Sunday in an email to the US Congress that it had approved key certification test flights.
Test flights had been planned for last year, but investigations uncovered new safety issues.
The aircraft cannot return to service until it receives final approval from the FAA, which said it does not yet have a date for when the grounding will be lifted.
Boeing had hoped to receive full approval for the plane to fly passengers by the middle of the year. However, many airlines have pushed back orders of the aircraft because of Covid-19.
In a letter seen by CNN, Boeing said: “Flights with FAA test pilots could begin as early as tomorrow, evaluating Boeing’s proposed changes to the automated flight control system on the 737 Max.
“Testing is expected to take several days, and will include a wide array of flight manoeuvres and emergency procedures to enable the agency to assess whether the changes meet FAA certification standards.”
The FAA’s letter to Congress said the start of test flights does not signify the agency has ‘completed its compliance evaluation or other work associated with return to service’.
The letter outlines the steps that will remain in the clearance process following the test flights, which include evaluating minimum pilot training requirements and other processes.