Ryanair veteran Eddie Wilson is to replace Michael O'Leary as chief executive of the group's main airline, effective 1 September.
O'Leary will become chief executive of the holding company that oversees Ryanair, its Austrian subsidiary Lauda, Polish unit Buzz, and Malta Air.
Wilson has been at the Irish low-cost carrier for 22 years and is currently Ryanair's chief people officer – in which position he has been intensely involved in the airline's often fractious relations with employee unions.
O'Leary says Wilson will report to him as group chief, joining the company's weekly meeting alongside the chief executives of Buzz, Lauda and Malta Air.
"We hope he will build on the successful improvements that the airline has delivered over the last 12 months, particularly as we enter into very difficult times," O'Leary wrote in a note to staff, referencing the challenge of Brexit at the end of October, as well as the Boeing 737 Max crisis that will result in the airline having at least 30 fewer aircraft this winter "and possibly the same number, or even more, again next summer".