Four star admiral

A four-star rank is the rank of any four-star officer described by the NATO OF-9 code. Four-star officers are often the most senior commanders in the armed services, having ranks such as (full) admiral, (full) general, or air chief marshal. This designation is also used by some armed forces that are not North Atlantic Treaty Organisation (NATO) members.

In the Australian Defence Force the following ranks of commissioned officers are awarded four-star ranks:

The four-star rank is reserved in Australia for the Chief of the Defence Force, the highest position in peace time.

In times of major conflict, the highest ranks are the five-star ranks: admiral of the fleet, field marshal, and marshal of the Royal Australian Air Force.

The four-star rank is reserved in Brazil for the highest post in the military career. The officers in this position take part of the high command of their corporations. The commanders of army, navy and air force are also four-star generals, but they have precedence to all the others military in this rank.

General/Admiral is the highest rank within the Canadian Armed Forces as defined within the National Defence Act. Usually, only one officer, the Chief of the Defence Staff, carries the rank of full admiral or general at any one time. However, the crown may authorize additional officers at that rank for special cases such as for Canadian officers in the position of Chairman of the NATO Military Committee, who are usually former Chiefs of the Defence Staff seconded to NATO for that duty.

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