Group captain is a senior commissioned rank in many air forces. Group captain has a NATO rank code of OF-5, meaning that it ranks above wing commander, immediately below air commodore and is the equivalent of the naval rank of captain and the rank of colonel in other services.
While the rank originated in the British Royal Air Force (RAF), group captain is a rank used by the air forces of many Commonwealth and other countries that have been influenced by British military culture. It is sometimes used as the English translation of an equivalent rank in countries which have a non-English air force-specific rank structure.
It is usually abbreviated Gp Capt. In some air forces (such as the RAF, IAF and PAF), GPCAPT is used while in others (such as the RAAF and RNZAF) and sometimes, especially in historical contexts, as G/C. The rank of group captain is not correctly abbreviated as "captain".
On 1 April 1918, the newly created RAF adopted its officer rank titles from the British Army, with Royal Naval Air Service captains and Royal Flying Corps colonels becoming colonels in the RAF. In response to the proposal that the RAF should use its own rank titles, it was suggested that the RAF might use the Royal Navy's officer ranks, with the word "air" inserted before the naval rank title. For example, the rank that later became group captain would have been "air captain". Although the Admiralty objected to this simple modification of their rank titles, it was agreed that the RAF might base many of its officer rank titles on naval officer ranks with differing pre-modifying terms. It was also suggested that RAF colonels might be entitled "bannerets" or "leaders". However, the rank title based on the Navy rank was preferred and as RAF colonels typically commanded groups the rank title group captain was chosen. The rank of group captain has been used continuously since 1 August 1919.