XP841

XP841 was the only HP.115 built. Handley Page was authorised in late 1959 to build a single powered research aircraft, and made it at Cricklewood. The project had started as a glider, the Slingsby T.48, but a powered design promised more flying time for the money.

J.M. Henderson flew XP841 for the first time on 17 August 1961 at the Royal Aircraft Establishment, Bedford. Contractor trials ended on 29 September 1961. From then on it flew for the RAE, studying how a slender delta wing behaved at low speed. That work fed the programme that produced Concorde.

Test pilots showed the aircraft stayed controllable down to about 69 mph. It later carried Hartmann noise generators for acoustic research, and the RAE filmed its trials in 1970. After two minor mishaps it made its final flight on 1 February 1974, having logged roughly 500 hours.

On retirement it went to the RAF's historic aircraft collection at Colerne. When that closed it moved to the RAF Museum at Cosford. It came south to Yeovilton when the Fleet Air Arm Museum opened its Concorde display, joining the BAC 221 and Concorde 002.

The HP.115 has been shown with the BAC 221 and Concorde 002 in the museum's supersonic display; some listings place it in the reserve collection, so check before travelling to see it.