The board, which had stood behind Mr. Muilenburg for months as he became a magnet for public outrage, decided to remove him after last week’s turmoil, including the decision to temporarily shut down the 737 Max factory and the botched launch of a Boeing space capsule designed for NASA.

Looking back: Mr. Muilenburg repeatedly made overly optimistic projections about how quickly the Max would return to service, creating chaos for airlines, which had to cancel thousands of flights and sacrifice billions of dollars in sales. His attempts to publicly apologize for the crashes of the Lion Air and Ethiopian Airlines flights were clumsy, and his relationship with the Federal Aviation Administration was in tatters.

Ahead: David Calhoun, Boeing’s chairman, will replace him next month, and the chief financial officer, Greg Smith, will serve in the interim. Before the Max can fly again, Boeing and regulators must fix an automated system known as MCAS that was found to have played a role in both crashes.