| Pitcairn PA-33 / PA-34 | |
|---|---|
 | |
| A still of a Pitcairn PA-34 Autogiro from a film clip of the aircraft flying circa 1930s. | |
| Role | reconnaissance autogyro |
| National origin | United States |
| Manufacturer | Pitcairn |
| First flight | 1936 |
| Number built | 1 x PA-34, 1x PA-33 |
The Pitcairn PA-34 and Pitcairn PA-33, given the United States Navy (USN) designation Pitcairn OP-2 and United States Army (US Army) designation Pitcairn YG-2 respectively were reconnaissance autogyros designed and built in 1936 for evaluation.
The Pitcairn Aircraft Company built and developed auto-gyros under licence from the Cierva Autogiro Company, trading as the Pitcairn-Cierva Autogiro Company from the late 1920s. Interest in the auto-gyro by the USN resulted in the purchase of two Pitcairn PCA-2 autogyros, modified as two-seat observation platforms, designated XOP-1. Trials with the XOP-1s from 1931 had limited success, but included an operational deployment in Nicaragua from June 1932, with the United States Marine Corps (USMC). [1]
Following the development of much-improved rotor and control systems, further interest by US armed forces resulted in the Pitcairn PA-33 (YG-2) and Pitcairn PA-34 (XOP-2). These essentially identical aircraft differed mainly in undercarriage design; the PA-33 had fully cantilevered oleo-pneumatic undercarriage legs and the PA-34 had strut mounted split axles with oleo-pneumatic shock-absorbers attached to the top fuselage longerons. [1]
The fuselage was constructed of welded steel tube with fabric covering and light alloy fairings. The 3-bladed folding rotor was mounted on a braced bi-pod with legs fore and aft of the front cockpit. The tail unit consisted of a very wide chord fin and rudder with a strut supported tail-plane sporting up-turned wing-tips. Tail surfaces were constructed of wood with fabric covering and rotor blades were built with steel tube spars and plywood ribs with fabric covering. [1]
Accommodation was in tandem cockpits with the pilot in the rear cockpit aft of the rotor support bi-pod and the observer in the front cockpit beneath the rotor head. [1]
Power was supplied by a nose-mounted 420 hp (310 kW) Wright R-975E-2 in a tight-fitting wide chord cowling with blisters to accommodate rocker arms. The engine was mounted with considerable nose-down angle to ensure prop-wash over the rotor to maintain rotation and ease rotor starting. [1]
Control of the aircraft was achieved only by use of the throttle and the tilting rotor-head, operated by a hanging control stick in the rear cockpit. [1]
The YG-2 and OP-2 were briefly tested by the US Army and US Navy, with limited success. After completing tests with the US Army, the YG-2 was taken over by the National Advisory Committee for Aeronautics (NACA). registered as NACA 88. On 30 March 1936, whilst on test, NACA 88 suffered a rotor failure, prompting the crew to perform the first successful bail-out from a rotary-winged aircraft. [2]
Data from Jane's all the World's Aircraft 1938 [1]
General characteristics
Performance
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