One of the most famous machines of the Cold War the Phantom F-4 was operated by both the Royal Navy and in an altered form by the RAF from the late 1960s until the early 1990s The Royal Navy was the first export customer for the F-4 but wished to retail engine commonality across its carrier-born fast jet fleet so opted for their Phantoms to be powered by the Rolls Royce Spey jet engine This is necessitated a subtle redesign of the rear fuselage to accommodate the new engines as well as changes to the electrical systems The Royal Navy Phantoms were designated FG 1 with later machines for the RAF designated FGR-2 The Royal Navy Phantoms operated from the carrier HMS Ark Royal and were the only Phantoms operated at sea by another power outside the USA But after the retirement of the Navy's large aircraft carriers the Phantoms were passed to the RAF In both air arms the Spey powered Phantoms proved to be a popular machine able to carry large loads of ordinance a long way While the Phantom never saw combat in British hands it was always regarded as a capable and powerful asset to Britain's Cold War defences