PARIS — Faced with mounting criticism from European governments over production problems with its newest military transport plane, the Airbus Group on Thursday announced a management shake-up at its military aircraft unit and promised a restructuring of the business to address what it said were “unacceptable” delivery delays.

In a statement, Airbus said that Domingo Ureña-Raso, who as head of military aircraft was in charge of development of the A400M Atlas cargo plane, had resigned and would be replaced by Fernando Alonso, the group’s head of flight testing.

Mr. Alonso, 58, will start in his new role on March 1, Airbus said. Until then, Bernhard Gerwert, chief executive of the group’s defense and space division, will serve as acting military aircraft chief.

The switch comes just months after Airbus acknowledged that production snags with the plane, which cost 20 billion euros, or about $22.7 billion, to develop. The problems pushed back delivery of the planes to some European militaries, including Germany, France and Britain and risked adding to the €4 billion in expenses that the group had already absorbed since 2006.