The Wireless Operator (air) half brevet was introduced in 1943. . The first half brevet was introduced between 1915 and 1918 for Observers. This remained the only one until that for Air Gunners was introduced in 1939, which introducing the pattern of letters contained in a wreath that was followed by all subsequent such half brevets. The growth in such brevets was driven by the introduction of larger aircraft and therefore larger crews with specialist skills. The half brevets were worn in the same manner as the pilots’ flying badge, on the left breast, above the medal ribbons. Several variants of the brevets exist, with the number of feathers ranging from twelve to seventeen.