Assistant Chief of Air Staff

The Assistant Chief of the Air Staff (ACAS) is a senior appointment in the Royal Air Force.

The ACAS post was established in 1985 by eliminating the Vice Chief of the Air Staff and combining the Policy and Operations two star assistant chiefs. In 1992, ACAS became a member of the Air Force Board. The ACAS is responsible for "Assisting the Chief of the Air Staff in generating a balanced and integrated Royal Air Force capability and for maintaining the fighting effectiveness and morale of the Service including the development of policy." One of the many duties of the ACAS is to sit on the board of the Civil Aviation Authority as a non-executive member.

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