WASHINGTON — In a small step toward returning Boeing Co.’s 737 Max to service, U.S. regulators are revising requirements for how airlines must operate the plane if equipment breaks down.
The U.S. Federal Aviation Administration on Thursday issued proposed new rules for airline operations on the Max that adapt to the fixes being finalized for the grounded jetliner. The public will have 30 days to comment on the document, which was posted on the FAA’s website.
Boeing is finalizing changes to a flight-control system linked to two fatal crashes, in Indonesia and Ethiopia, that killed 346 people. The manufacturer is also altering the plane’s flight-control computers after tests showed they were vulnerable to failure.
The company must complete an audit of the software changes and test the revised system in flight simulators with a variety of pilots. In addition to signing off on the redesign, the FAA is also devising new pilot training.
One of the more technical steps in the process is to revise what is known as the Master Minimum Equipment List, which lays out conditions under which an operator can fly the aircraft with a variety of malfunctions. Major breakdowns require that a plane get fixed before flight, but airlines can fly with relatively minor malfunctions if there are adequate backups and repairs are performed within a prescribed time.
Because of revisions to the 737 Max’s flight computers — which will be checking each other in Boeing’s proposed new design — the FAA is changing requirements for how airlines operate if the computer or related functions aren’t working properly.
“This is a positive sign of the measured approach for ensuring the safe return to service of the 737 Max and the thorough approach by the FAA in this process,” Boeing spokesman Paul Bergman said in an email on Thursday night.