The head of Boeing's embattled 737 MAX program plans to retire, the company said Thursday, just as it gears up to persuade regulators to return the plane to the skies after two deadly crashes.

It was the most high-profile departure of a ­senior executive since the aircraft was grounded in mid-March following two crashes that claimed 346 lives. Eric Lindblad, who has led the MAX program since August 2018, will step down and work with his successors on a transition.