P/O - Pilot Officer (Second Lieutenant) - a pair of thin stripes
F/O - Flying Officer (First Lieutenant) - a pair of thick stripes
F/L - Flight-Lieutenant (Captain) - 2 pairs of thick stripes
Sq/L - Squadron Leader (Major) - a pair of thin stripes between 2 pairs of thick stripes
W/C - Wing-Commander (Lieutenant Colonel) - 3 pairs of thick stripes
Group Captain (Colonel) - 4 pairs of thick stripes
Air Commodore (Brigadier General) - a pair of very thick stripes
Air Vice-Marshal (Major General)
Air Marshal (Lieutenant General)
Air Chief Marshal (General)
Marshal of the RAF (General of the Air Force)