One of the longest managerial reigns in the world of aviation ends with Akbar Al Baker’s resignation as chief executive of Qatar Airways.

As of Nov. 5, Qatar Airways’ CEO Al Baker will step down after leading the airline since 1997. Qatar Airways did not provide a reason for his departure, and the move was unexpected. Badr Mohammed Al Meer, the chief operating officer of Doha Hamad Airport, which serves as the airline’s base, will replace him.

Known as one of the industry’s most outspoken and influential executives, Al Baker transformed Qatar Airways into one of the world’s top airlines. During his 27-year tenure, he oversaw aggressive expansion and investment in Doha airport, which now serves as a global hub. Currently, Al Baker is the airport’s chief executive officer.

With his forthright views on the airline industry, Al Baker often courted controversy. He predicted that the industry’s net zero targets would be missed in June.

During a meeting of the International Air Transport Association in 2018, Al Baker apologized for making sexist remarks.

Despite gender inequality in the industry, Al Baker believes Middle East airlines should be led by men, “since it is a very challenging job.”

Al Baker apologized after the comments caused uproar, saying “it would be my pleasure to help develop a female candidate to become Qatar Airways’ CEO.”