 The RAF later received Hunters equipped with an improved Avon engine. The Avon 203 produced 10,000 lbf (44.48 kN) of thrust and was fitted to XF833, which became the first Hunter F.6. Some other revisions on the F.6 included a revised fuel tank layout, the centre fuselage tanks being replaced by new ones in the rear fuselage; the "Mod 228" wing, which has a distinctive "dogtooth" leading edge notch to alleviate the pitch-up problem; and four "wet" hardpoints, finally giving the aircraft a good ferry range. The Hunter F.6 was given the company designation Hawker P.1099.
