I've noticed a lot of confusion going on recently between the term Airman and Aircrew.
The term Aircrew refers to Pilots, Weapons Systems Officers or Weapons Systems Operators, i.e. people who operate aircraft for a living and is nothing to do with rank.
Pilots and WSOs are Commissioned Officers, WSOps are Airmen or Warrant Officers.
The term Airman/ Airmen refers to members of the Royal Air Force who are not Commissioned Officers or Warrant Officers. Comprised of the ranks from Aircraftsman through to Flight Sergeant. Is the equivalent of Soldier in the Army or Sailor in the Navy.