The Curtiss R-3 was a twin float version of the Curtiss R-2 observation aircraft, and although only two were completed, it was followed by the more numerous R-6 and R-9.
The R-2 was the first production version of the Curtiss Model R, which had been developed as a larger and more advanced version of their first successful tractor aircraft, the Model J and Model N. Twelve had been sold to the US Army in 1916 and 100 using a Sunbeam Arab engine went to the British (probably the RNAS).
The R-3 was a twin float version of the R-2. In order to compensate for the extra weight of the floats, both wings were lengthened. A new central section was produced for the upper wing, extending it by just over 11ft, while an extra wing panel was installed between the fuselage and the normal lower wings. The wings were level, without the dihedral used on the R-2. The R-3 was otherwise very similar to the R-2, with the same tail, two widely separated cockpits (with the observer between the wings and the pilot in the rear fuselage), ailerons in the upper wings, and powered by the same Curtiss V-X engine.
Only two R-3s were produced, and they were delivered to the US Navy in 1916, with the serial numbers AH-62 and AH-65. After 18 May 1917 they became A66 and A67.
A66 was allocated to USS Seattle in April 1917, then to NAS Bay Shore and NAS Huntingdon, Long Island. It was badly damaged in November 1917, and struck off charge at Bay Shore on 12 January 1918.
A67 was based at Pensacola in January 1917, and was badly damaged in a hard landing in August 1918. It was struck off charge on 11 November 1918.
The US Army placed an order for eighteen R-3s in 1916, to be delivered in 1917. However these aircraft appear to have been delivered as the R-6 and R-9. US Serial numbers suggest that the first aircraft may have been delivered as R-3 serial number 504, and the remaining seventeen (509-521) as the R-6.
Engine: Curtiss V-X
Crew: 2 – pilot and observer
Span: 57ft 1 1/32in
Length: 30ft 11 1/2in
Empty weight: 3,000lb
Gross weight: 3,837lb
Maximum take-off weight: