High-wing light monoplane with welded tubular steel frame fuselage. The wings have internal wooden spars and aluminium cross-members. Wings, fuselage and tailplane are encased in canvas which has been stretched tight by means of the application of dope.
The plane has two rubber-tyred wheels on elastic-sprung struts below the cabin, and a small sprung tailwheel. The aircraft is painted in military camouflage colours.
The Mk9, developed in 1954, was the last military model produced by Auster Aircraft Ltd. 182 were supplied to the British and Indian armies and they were in service throughout the world.
Normally carrying a pilot and an observer, it also had additional seating for one passenger. Improved landing gear and tyres allowed it to take off and land on rough surfaces. The rear floor of the cockpit was also easily detachable, allowing it to be used for casualty evacuation, photography, cable laying and supply dropping.
However, the Auster's role as an Air Observation Post began to be replaced by the helicopter. The aircraft were taken out of service in 1966, ending their 25-year relationship with the Army.
XP 280 was one of the last Mk 9's produced. It had been stored at RAF St Athan in 1966 where it stayed until 1974 when it was bought by Leicestershire Museums Service.