Parachute hook knives and a jet on the handle
The Royal Air Force, formed on 1 April 1918, was the world's first air force independent of an army or navy, and other countries followed in the decades after. As flying grew, so did the kit carried by aircrew, including small hook knives for cutting tangled parachute lines, with the edge hidden inside a curve so it could not cut the wearer.
That hooked, recessed edge is the same idea behind the seatbelt cutter at the rear of this handle, and of any good fireman's knife today. On this model it sits beneath an AIR FORCE shield with a climbing fighter jet, etched on 11.7 cm of black aluminium, with an 8.5 cm black tanto blade ready for everyday cuts.
