McDonnell Douglas Phantom F.G.1, Royal Air Force Users

Given the cancellation of some of the Royal Navy's carriers in the late 1960s and early 1970s, a total of 20 airframes that were intended for the Fleet Air Arm, were diverted to the Royal Air Force to be assigned to the air defence role. Considering the many flaws of the English Electric Lightning, that was the main interceptor of the RAF at the time, like its limited range, weapons fit and loiter time, its effectiveness was really hampered, specially when long range interception of Soviet airplanes over the North Sea and North Atlantic. That's why a new Phantom equipped squadron was formed at RAF Leuchars, that was RAF's most Northern air base, to take advantage of the Phantom's improvements over the Lightning as it could carry more fuel giving it a longer range.
It was also fitted with a better radar and could carry more missiles, a total of eight against the two that the Lightning could carry.
On 1st September 1969, No.43 Squadron was formed at RAF Leuchars, operating as part of the QRA zone together with the Lightnings of the No.11 Squadron and, from 1972, the Royal Navy's Phantoms of the 892 Naval Air Squadron.
When the HMS Ark Royal (R09) was withdrawn to be decommissioned in 1978, the Phantoms of the Fleet Air Arm, were given to the Royal Air Force in order to form a second squadron, the No.111 Squadron also at RAF Leuchars.
The squadrons that employed the Phantom F.G.1 were these ones:

• No.43 Squadron: As mentioned previously, they received the Phantom F.G.1 at RAF Leuchars on 1st September 1969, which they flew it until its replacement by the Panavia Tornado F.3 in September 1989.
• No.64 (R) Squadron: Since 1967 the squadron has been the reserve identity of the No.228 OCU squadron, in order to flight the Phantom FG.1, first from RAF Coningsby and from RAF Leuchars later. When the OCU squadron was disbanded on 31st January 1991, so was the No.64 Squadron.
• No.111 Squadron: This squadron received the surplus of Phantoms F.G.1 in 1974 at RAF Coningsby and then they moved to RAF Leuchars. They were re-equipped with the Panavia Tornado F.3 in 1990.

Sources:

1. https://en.wikipedia.org/wiki/McDonnell_Douglas_F-4_Phantom_II#United_Kingdom

2. https://en.wikipedia.org/wiki/McDonnell_Douglas_F-4_Phantom_II_in_UK_service

3. Salamander Books - The Complete Book of Fighters