The Lockheed R3O was the designation for two versions of the Model 10 Electra used by the US Navy, one purchased for the Navy and one impressed during the Second World War
The XR3O-1 was delivered to the US Coast Guard on 9 April 1936. It was based on the Model 10-B and was powered by two Wright R-975E-3 engines. It was used as a personal transport by the Secretary of the Treasury
The Lockheed Model 10 Electra was one of the first aircraft to be designed after Robert Gross took over Lockheed in 1932. It was a twin engined airliner, with low mounted tapered wings, a high mounted tail with twin vertical control surfaces at the ends and a flat sided fuselage. The standard version had a series of cabin windows, with the passenger door on the left side of the fuselage, half way between the wings and the tail. The same basic layout would be used on a long series of Lockheed airlines, all of which sold in reasonable numbers, while being out-shadowed by the Douglas DC-2/ DC-3 family.
The XR3O-1 had originally been ordered as an identical aircraft to the Pratt & Whitney powered R2O-1, but by the time it arrived the engines had been changed to the Wright R-975E-3, and the interior had been modified so it could be quickly be changed from a VIP transport into an air ambulance. It remained in military service until the end of the Second World War, when it was sold into civil service. It was one of the longest serving Electras, before ditching on a beach in 1967.
The designation R3O-2 was given to a single example of the six-seat Lockheed 12-A Electra Jr that was impressed for military service during the Second World War.
Engine: Two Wright R-975-E3 air cooled radials
Power: 440hp each
Wing span: 55ft
Length: 38ft 7in
Gross weight: 10,100lb
Maximum weight: 143,600lb
Maximum speed: 205mph
Lockheed Aircraft Since 1913, René J Francillon