Robert Cooper's PA-39 N3908 pictured some years ago. It is currently owned by the EAA and has been restored to represent one of the RAF PA-39s, but is currently lacking its rotor blades.

Restored Pitcairn PA-39 painted to represent RAF aircraft BW830 (which was actually lost at sea on January 19, 1942), awaiting completion in Steve Pitcairn's hangar and pictured in February 1989.

The Autogiro is powered by a 175 h.p. Warner Super Scarab 165D seven-cylinder radial engine.

Pitcairn PA-39 BW830's first run-up for some 30 years.

A final view of the PA-39’s recent run-up. The rotor is unpowered in flight - it simply windmills - but a clutch system connected to the engine allows it to be run up to take-off speed while the aircraft is stationary on the ground.

Another view of owner Steve Pitcairn running-up the PA-39 recently, for the first time in 30 years.

The Pitcairn’s tail surfaces. The outward-canted tip fins utilise the rotor downwash to help counteract the propeller torque.

To compensate for the Autogiro’s high centre of gravity the engine has about 6° of downthrust.

The PA-39’s rotor head. Steve Pitcairn replaced the original rotor blades, which were destroyed in a landing accident in 1960, with units from a Piasecki HRP-1 helicopter. A set of 6 3/4 in-long extensions were specially manufactured to adapt the new blade-roots to the old hub.

The Pitcairn PA-33 (Army YG-2) Two-seat Observation Autogiro (420 h.p. Wright "Whirlwind" engine).

... PHILADELPHIA IN THE MORNING. This is the latest type of Autogiro to be delivered to the U.S. Army Air Corps, it is a product of the Pitcairn factory and has a Wright Whirlwind engine of 420 h.p., which is reported to give a maximum speed approaching 150 m.p.h. Here the machine is seen on a test flight prior to delivery at Wright Field, Dayton, Ohio, for official tests.

The PA-33 (YG-2) observation Autogiro.

The Pitcairn PA-34 (Navy XOP-2) Two-seat Observation Autogiro (420 h.p. Wright "Whirlwind" engine).

PA-39 BW833 at Boscombe Down in December 1941. On November 19, 1942, it was damaged beyond repair.

Rare photograph of the Pitcairn PA-39 Autogiro, BW-829.

PA-39 BW829 at the factory in late 1941. It never arrived in Britain - along with two others, it was lost when the ship carrying it across the Atlantic was sunk by a U-boat in January 1942.

RAF PA-39s immediately after assembly in late 1941.

One of Pitcairn's autogiros, developed after Harold Pitcairn acquired the Cierva licence: a PA-39 for British evaluation in World War II.

Robert Cooper’s PA-39 N3908. The Autogiro is currently preserved by the EAA.

Pylon and rotor head of Robert Cooper’s PA-39 N3908

The PA-39’s cockpit has conventional-style main controls.

Cockpit of Robert Cooper’s PA-39 N3908

PA-39