Radioplane OQ-2 - version overview
RP-4 - 1940, unmanned radio-controlled target aircraft with a Righter engine driving two partially intermeshing propellers; 53 for the US Army.
OQ-1 - designation sometimes mentioned as service for RP-4, but it is not documented.
OQ-2 - 1941, RP-5 model, welded fuselage frame, "classic" contra-rotating propellers; probably just prototypes.
OQ-2A - 1942, RP-5A, serial form of OQ-2, simplified design. 984 pcs.
OQ-2B - lightweight version with holes in the wing ribs. Credited in OQ-2A.
OQ-3 - 1943, OQ-2 with reinforced hull, more powerful engine, single propeller, no landing gear. 9403 pcs.
OQ-5 - 1943, RP-7, square fuselage and self-supporting wings covered with plywood. Prototype only.
OQ-7 - 1943, mid-plane OQ-3 with a slight sweep for better performance. Prototypes only.
OQ-12 - 1943, RP-6, oval fuselage and self-supporting wings, contra-rotating propellers. Prototype only.
OQ-14 - 1944, RP-8A, wing level with the upper edge of the fuselage (earlier versions had it extended slightly upwards) , four-cylinder O-45-1 engine (the RP-8 prototype was twin-engined). 3548 pcs.
TDD-1 - 1942, OQ-2A given to US Navy, without landing gear. Most of the OQ-2As were probably given to the US Navy.
TDD-2 - 1943, OQ-3 given to US Navy.
TDD-3 - 1944, OQ-14 given to US Navy.
TDD-4 - 1944, US Navy OQ-14 completed with O-45-35 engine.
A-2A - original designation for the OQ-2A, changed before the prototype took off.
Other prototypes:
RP-9 - 1944, like the OQ-14 but with a higher wing and a more powerful engine.
RP-10 - 1944, low-wing similar to the OQ-14 with a slight wing sweep, 20 hp engine.
RP-11 - 1944, low-wing similar to the OQ-14 with a slight wing sweep, 17 hp engine.
RP-12 - 1944, OQ-3 with the wing level with the upper edge of the fuselage and the trailing edge running into the side of the fuselage.
RP-13 - 1944, OQ-3 with shortened nose due to Kiekhaefer engine installation.
