Boeing hopes to resume 737 MAX flights later this year despite major airlines cancelling service until January-February.

The Boeing Company is making progress towards getting its 737 MAX aircraft in the air again, but the United States Federal Aviation Administration (FAA) will need at least several more weeks for review, FAA Administrator Steve Dickson said on Tuesday.

Boeing and the FAA are grappling to contain a crisis in the wake of two 737 MAX crashes that have left 346 people dead, forced airlines to ground more than 300 aircraft, and put on hold Boeing deliveries worth more than $500bn.

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Boeing has said it hopes to resume 737 MAX flights later this year, although major US and Canadian airlines have cancelled MAX flights until January or February.

Dickson said at a conference of air traffic controllers in Washington that the agency had received the “final software load” and “complete system description” of revisions to the plane, which was grounded in March.

The FAA is currently using “aircraft production software” in the engineering simulator. The next step is to complete pilot workload management testing and have US and international pilots conduct scenarios to determine training requirements before a key certification test flight.

“It is going to be several more weeks before we go through all of that part of the process,” Dickson said. “We’ve got considerable work to do.”

Separately, Boeing said that last week that it successfully conducted a dry run of a certification flight test. Dickson told Reuters news agency last month the FAA would need about 30 days from the time of the certification test flight before the plane could resume flights.

The system description is a “500-ish page document that has the architecture of the flight control system and the changes that they have made,” Dickson told Reuters last month.

Significant progress

Boeing shares rose on Tuesday after two sharp days of declines following the Friday release of instant messages from a former Boeing pilot. The company had withheld the messages from the FAA – and they raised questions about what Boeing may have known about a key safety fixture: the 737 MAX’s Maneuvering Characteristics Augmentation System (MCAS) anti-stall software.

The release of the messages prompted an immediate demand for an explanation from the FAA about why they were not turned over sooner.

Boeing said on Tuesday it had “made significant progress over the past several months” in its work to return the MAX to service.

The changes include an MCAS software update with new safeguards for the anti-stall system, which was at the heart of the two fatal crashes.

Dickson said once the steps were completed ahead of the certification test flight “it is a fairly straightforward process to unground the airplane”. He reiterated he would not let the 737 MAX fly again until he was “satisfied it is the safest thing out there”.

Boeing chief executive Dennis Muilenburg will appear before the US Congress for two days of testimony next week. He was stripped of his title as board chairman earlier this month.

On Wednesday, Indonesia plans to share with victims’ families a final report on Lion Air flight 610, which crashed into the Java Sea shortly after takeoff from Jakarta on October 29, 2018, killing all 189 people on board. The report on the 737 MAX crash is expected to be made public later this week.

The MAX was grounded after a second crash on March 10 that involved Ethiopian Airlines flight 302 and that killed 157 people.