Hawker Siddeley Harrier AV-8As to the AV-8C configuration—the work focused mainly on extending useful service lives and improving VTOL performance. The AV-8C and the remaining AV-8A Harriers were retired by 1987. These were replaced by the Harrier II, designated as the AV-8B, which was introduced into service in 1985. The performance of the Harrier in USMC service led to calls for the United States Air Force to procure Harrier IIs in addition to the USMC's own plans, but these never resulted in Air Force orders. Since the late 1990s, the AV-8B has been slated to be replaced by the F-35B variant of the
British Aerospace Harrier II programme. In July 2008, Qinetiq was awarded a contract to perform upgrades and maintain the Harrier II fleet until 2018, which was the predicted out of service date for the type. The first squadrons to receive the Harrier II were based in Royal Air Force Germany, a standing force maintained to deter Soviet aggression against the West and, in the event of war, to carry out ground attacks. As the Harrier II had significantly greater range and survivability than its predecessor the Hawker Siddeley Harrier, a new emphasis was placed on interdiction operations. By the end of 1990, the Harrier