And to add to the confusion. In the RAF, the forage cap is their term for the wedge cap (as worn by a well known individual shown below) and is an optional item of kit. In another thread some comments were made about the manner in which he was wearing this head-dress which does not seem to conform to that service's instructions. But then the only photo of a pers wearing the item in their dress instrs does not provide a good example of correct wear (see below). (BTW, the optional leather flying jacket as shown in the photo can be worn with aircrew dress but can not be worn while flying aircraft.)
AP 1358 Uniform Dress and Appearance Regulations for the Royal Air Force
Chapter 1 - General Instructions on Uniform Dress and Appearance
Wearing of Head-dress
0124. When wearing uniform outdoors, on or off base, headdress is to be worn by all personnel in the following manner:
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b. Forage Cap. The forage cap, which is an optional extra at own expense, is worn tilted to the right so that that front edge is approximately 25mm above the eyebrows and the side edge is approximately 12mm above the right ear. The material is blue/grey worsted barathea of standard styling for wg cdrs and below; for gp capts and air officers the cap is piped in minerva blue. The forage cap is never worn with CS 95.
Chapter 6 - Aircrew Orders of Dress
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0614. Black Leather Flying Jacket – (No 14C dress). A blue leather flying jacket of the standard approved pattern (in accordance with RAF GAI 6076) may be purchased at personal expense and worn with flying clothing, on the ground only. See Para 0615.
0615. Mixing of Uniform. Cold weather flying jackets, cold weather trousers, CS95 outer jackets and blue leather flying jackets, are only for wear with service issue flying suits. Under no circumstances are any of these items to be worn with other orders of dress e.g. No 2 Dress uniform.