Pratt and Whitney R1340 Wasp
The R-1340 aircraft engine was the first engine produced by the Pratt and Whitney aircraft engine company in 1925, and was the first of the renowned Wasp series of engines. It was a nine cylinder, single row, supercharged and air cooled radial engine with a power output of from 410 to 600hp depending on the variant, and it was designed to meet a US Navy requirement for an engine with a maximum weight of less than 650lbs and a power output of 400hp.
This was to power aircraft that would equip two new aircraft carriers, the USS Lexington and the USS Saratoga.
The first prototype completed on December 24, 1925 was rated on test at 410hp. Further development increased the power output to the ultimate 600hp, with a reputation of reliability.
Between 1926 and 1966 when production ceased, 34,966 R-1340 units had been built by Pratt and Whitney and licensees, that included the Commonwealth Aircraft Corporation (CAC), and powered many aircraft types including the Australian CA-1 Wirraway, the US Lockheed 10, Ford Trimotor and Gee Bee Super Sport Star, and de Havilland Canada DHC-3 Otter among others.
Many examples of the R-1340 engine still operate in aircraft to this day including the North American Harvard, and one is on display at the Museum.
Bore and Stroke
Power to weight ratio
9 cylinder single row air cooled radial piston engine
Square @ 5.75in (146mm)
1,344 cu in (22.02L)
2 overhead valves per cylinder
Single speed centrifugal
2 barrel Stromberg carburettor
542hp @ 2,200rpm @ 5,000ft (1,525m)