Hawker Siddeley much larger firms. Out of this decision, came the "order" that all future contracts being offered had to include agreements to merge companies. In 1959, Folland Aircraft was acquired, followed by de Havilland Aircraft Company and Blackburn Aircraft in 1960. In 1963, the names of the constituent companies were dropped, with products being rebranded as ""Hawker Siddeley"" or ""HS"". In this period, the company developed the first operational, and, by far, the most successful VTOL jet aircraft, the Harrier family. This aircraft remained in production into the 1990s and remains in service. In 1948, Hawker Siddeley acquired a factory in
Hawker Harrier it was underpowered, and it had an inferior bombload to the Hawker Horsley, the aircraft it was meant to replace. It was therefore modified to carry a torpedo. On testing the modified aircraft, however, it was found to still be underpowered, being incapable of taking off with a torpedo, gunner and full fuel load. It was therefore not considered further, the competition ultimately being won by the Vickers Vildebeest. The prototype was used by Bristol as an engine testbed, flying with the 870 hp (649 kW) Bristol Hydra and the Bristol Orion engines. Hawker Harrier The Hawker Harrier was an