Looking at 'Jeff' Jeffords book, RAF Squadrons, it gives June '65 as the date 78 Sqn changed from Twin Pin CC 1 to Wessex HC 2.
It then gives 13 Oct '67 as the date the squadron moved to Sharjah, where it stayed until disbanding on 21 Dec 71.
There appears to be no record of RAF Whirlwinds serving at Khormaksar - did the Royal Navy use them, and could they have been in Aden?