United Airlines extends cancellation of about 2,400 Boeing Max flights

United Airlines is cancelling another month’s worth of flights with Boeing 737 Max planes that were grounded after two deadly accidents.

United said Friday it has removed the Max from its schedule through Aug. 3 and will cancel about 2,400 flights in June and July as a result. It had previously cancelled all Max flights through early July.

Southwest and American have already dropped the Max from their schedules into August.

Boeing is making changes to flight-control software that investigators believe played a role in crashes in Indonesia and Ethiopia that together killed 346 people. The company is expected to soon formally submit its changes and a proposal for additional pilot training to the Federal Aviation Administration for approval.

The FAA held a meeting Thursday in Fort Worth, Texas, with nearly 60 officials from more than 30 countries to explain its process for analyzing Boeing’s changes to the Max. Acting FAA Administrator Daniel Elwell declined to give a timetable for the agency’s review, saying the FAA won’t allow the Max to return to the skies until it is convinced the plane is safe.

In a setback to FAA’s prestige, other regulators around the world grounded the plane in March after the second crash without waiting for the FAA to do so.

The FAA hopes that this time, other regulators — some of whom are doing their own separate reviews — will approve Boeing’s changes at the same time or soon after FAA does.

“Our review of the Max design changes, the software upgrade, is already under way,” said Nicolas Robinson, the head of civil aviation for Transport Canada, that country’s counterpart to FAA.

Robinson said, however, that it’s “difficult to put a time limit on that” because the length of the review will depend on how quickly Canada gets answers to questions it has about Boeing’s work.

United is using other planes to cover some flights that had been scheduled with its 14 Max jets.