Aircraftsman

Common military ranks in English
Navies	Armies	Air forces
Commissioned and Non-commissioned officers
Admiral of the fleet	Marshal or Field marshal	Marshal of the air force
Admiral	General	Air chief marshal
Vice admiral	Lieutenant general	Air marshal
Rear admiral	Major general	Air vice-marshal
Commodore	Brigadier or Brigadier general	Air commodore
Captain	Colonel	Group captain
Commander	Lieutenant colonel	Wing commander
Lieutenant commander	Major or Commandant	Squadron leader
Lieutenant	Captain	Flight lieutenant
Sub-lieutenant	Lieutenant or First lieutenant	Flying officer
Ensign	Second lieutenant	Pilot officer
Midshipman	Officer cadet	Flight cadet
Enlisted grades
Warrant officer or Chief petty officer	Warrant officer or Sergeant major	Warrant officer
Petty officer	Sergeant	Sergeant
Leading seaman	Corporal	Corporal
Seaman	Private	Aircraftman

Aircraftman (AC) or aircraftwoman (ACW) is the lowest rank in the British Royal Air Force (RAF) and the air forces of several other Commonwealth countries.

Aircraftman ranks below leading aircraftman and has a NATO rank code of OR-1. It is now a training rank only and no airmen in productive service hold this rank. Aircraftmen do not wear any rank insignia.

The rank was introduced on the formation of the RAF in 1918, replacing the Royal Flying Corps rank of air mechanic 2nd class. There were two grades: Aircraftman 1st class (AC1) and aircraftman 2nd class (AC2; also colloquially known as an "AC plonk").

In RAF slang, aircraftmen are sometimes called "erks".

In the Royal Canadian Air Force, the rank is known as "aviator". This was changed from private in spring 2015 when the RCAF changed the colour of its rank insignia from gold to pearl grey. It is the lowest rank in the RCAF. Prior to 1968 the rank of aircraftman was used in the RCAF as in other Commonwealth air forces.

The Royal Australian Air Force also uses both aircraftman and aircraftwoman.

In the Royal New Zealand Air Force, the rank is known as "aircraftman", regardless of the person's sex, in line with "seaman" in the Royal New Zealand Navy.

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