The first Harrier aircraft XV738 flew on 28 December 1967; this was the first aircraft of the RAF to have a head-up display avionics system. The first two-seat Harrier XW174 flew on 24 April 1969, later crashing at Larkhill in June 1969. The British Aerospace Sea Harrier XZ450 first flew on 20 August 1978; on 4 May 1982 this aircraft would be hit by anti-aircraft fire at Goose Green, killing the pilot with 800 Naval Air Squadron from HMS Hermes; the aircraft had no radar warning receiver (RWR), due to testing the Sea Eagle, so could not detect the Skyguard radar had locked on to it, being destroyed with the Oerlikon GDF (35mm) of GADA 601; it was the first Sea Harrier lost in the Falklands campaign.