The RAF was founded on 1st April 1918 from the Royal Engineers and the Royal Flying Corps. Army ranks were used at this time, although with differing rank badges.

In 1919 the Air Council announced a set of RAF ranks, derived from both Army and Royal Navy traditions - partly because the Navy and Army refused to allow the RAF to use their officer ranks!

• Took the following RN ranks: Commodore, (Group) Captain, Wing Commander, Squadron Leader, (Flight) Lieutenant
• Added Flight Sergeant

The RAF abolished the rank of Sergeant Major in April 1933, leaving only WO1 and WO2

They abolished the rank of WO2 in1939, leaving only WO - equivalent to the Army WO1.

In 1946, the RAF renamed its aircrew warrant officers Master Aircrew, a designation which still survives. In 1950, it renamed warrant officers in technical trades Master Technicians, a designation which only survived until 1964.

The WO appointments of RAF today are a set of Master Aircrew (MAcr) comprising:

• Master Signaller (MSig)
• Master Engineer (MEng)
• Master Air Electronics Operator (MAEOp)
• Master Air Loadmaster (MALM)

Other designations, such as Master Pilot and Master Navigator, once existed, but now these specialisations are only held by officers.

Chief Technician is the equivalent rank to Flight Sergeant for the technical trades