American Airlines delays Boeing 737 MAX return to June

American Airlines announced Tuesday that its Boeing 737 MAXes will remain off the schedule until June 4.

It's just the latest development in the jet's ongoing saga of trouble.

The global fleet of Boeing's newest single-aisle jet has been grounded since March 2019, following two overseas disasters that left 346 people dead.

Since the grounding was first announced, airlines have repeatedly revised their estimates for when the planes would return to service as the grounding has persisted far longer than first expected.

Sign up for the free daily TPG newsletter for more airline news.

Both crashes have been attributed in part to an automated flight control software that was designed to make the MAX handle more like previous generations of the 737. Problems with the software have proven more difficult to fix than expected, even as Boeing works with regulators, airlines and other stakeholders to get the planes re-certified.

Dennis Muilenberg, Boeing's previous CEO, spent much of the last year pledging that the MAX would be flying again before the end of 2019. That did not pan out, and Muilenberg was ousted just before Christmas as part of an effort by the Boeing to "restore confidence in the company."

New CEO David Calhoun has not put a timeline on the jet's return to service, and the early days of his transition have been mired in new chapters of the MAX debacle.

First, Boeing reversed its long-held position that MAX pilots should not need simulator training if they were certified to fly previous versions of the 737. That reversal may contribute to a prolonged reintroduction to service as airlines have to provide fresh training to scores of pilots with a limited number of simulators available.

Then, a trove of internal communications became public, further calling Boeing's safety culture into question and revealing the lengths to which the manufacturer initially went to dissuade airlines from using simulators to train their MAX pilots.

American's decision to pull the MAX from its schedules through June brings it in line with United, which previously announced a June return to service for its MAX fleet. Southwest currently has its MAXes slated to return to the schedule in April, but — like American and United — has repeatedly had to further delay the plane's return amid the prolonged grounding.

There is still no firm timeline as to when the MAX might be cleared to resume flying.