Seniority
Air Chief Marshal is a four-star rank and has a NATO ranking code of OF-9. An Air Chief Marshal is equivalent to a "full" Admiral or a "full" General in the United Kingdom, the United States and elsewhere.
The rank of Air Chief Marshal is immediately senior to the rank of Air Marshal but subordinate to Marshal of the Royal Air Force (or other national equivalent - see Marshal of the Air Force). Although no RAF officer has been promoted to Marshal of the Royal Air Force since the British defence cuts of the 1990s, British Air Chief Marshals are not the most senior officers in the RAF as several officers continue to retain the RAF's highest rank. These officers are still to be found on the RAF's active list even though they have for all practical purposes retired. A similar situation also exists in the Indian Air Force as the honorary promotion of Arjan Singh to Marshal of the Indian Air Force in 2002 resulted in Indian Air Chief Marshals no longer being the most senior IAF officers.
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