Air chief marshal

Air chief marshal (Air Chf Mshl or ACM) is a four-star air officer (NATO OF-9)[1] rank which originated with the Royal Air Force, where it is the most senior peacetime air force rank.[2][3] The rank is also used by the air forces of many countries that have historical British influence and it is sometimes used as the English translation of an equivalent rank in countries which have a non-British air force-specific rank structure. An air chief marshal is equivalent to an admiral in the Royal Navy or a general in the British Army or the Royal Marines. In other forces, such as the United States Armed Forces and the Canadian Armed Forces, the equivalent four-star rank is general or admiral.

Air chief marshal
An RAF air chief marshal's command flag
Shoulder and sleeve insignia from the Royal Air Force
A RAF Air Chief Marshal star plate
Service branchAir forces
AbbreviationAir Chf Mshl / ACM
RankFour-star
NATO rank codeOF-9
Non-NATO rankO-10
Formation1 August 1919 (1919-08-01) (RAF)
Next higher rankMarshal of the Royal Air Force
Next lower rankAir marshal
Equivalent ranks

The rank of air chief marshal is immediately senior to the rank of air marshal but subordinate to marshal of the Royal Air Force. Air chief marshals are sometimes generically considered to be air marshals.[4]