Hawker Siddeley Harrier to the pilot by a head-up display and a moving map display. The Harrier's VTOL abilities allowed it to be deployed from very small prepared clearings or helipads as well as normal airfields. It was believed that, in a high-intensity conflict, air bases would be vulnerable and likely to be quickly knocked out. The capability to scatter Harrier squadrons to dozens of small "alert pads" on the front lines was highly prized by military strategists and the USMC procured the aircraft because of this ability. Hawker Siddeley noted that STOL operation provided additional benefits over VTOL operation, saving fuel and
Invincible-class aircraft carrier to evolve. The order for the first ship was given to Vickers (Shipbuilding) on 17 April 1973. By now, the design was for a 19,000 ton "CAH" (helicopter carrying heavy cruiser, styled after the US Navy hull classification symbols) with up to fourteen aircraft and a Sea Dart missile launcher on the bows. The government decided that the carrier needed fixed-wing aircraft to defend against Soviet reconnaissance aircraft. In May 1975, it authorised the maritime version of the Hawker Siddeley Harrier, which was successfully developed into the Sea Harrier. This meant that the design was reworked again to include a