Never given its own name by the RAF, the new design entered service in 1964 as Red Top. It was faster and had a longer range than Firestreak, and "was capable of all aspect homing against super-sonic targets." Despite Red Top being intended to replace Firestreak, Firestreak remained in limited service until the final retirement of the Lightning in 1988; Red Top's larger fins required more vertical tail to stabilize the effects of its larger wings, so Firestreak remained in use on older models of the Ligntning.