The Wright R-3350 was a critical development for the success of the Boeing B-29, its major airframe application. Early versions of the R-3350 encountered lubrication and cooling problems, and a fuel-air mixture problem that led to some backfires and destructive engine fires. Engineers later solved the problem by replacing the carburetors with a fuel-injection system.

Twin turbo-superchargers were installed in each engine to compress the thin air at high altitudes. The long nose case of the engine contained a gear reduction drive, which permitted the propeller to turn at slower speeds than the engine, producing greater efficiency.

A total of 6,958 Wright Cyclone R-3350-57 engines were built between January 1944 and November 1945, and powered the Boeing B-29/A/B, XB-29E, RB-29/A, TB-29/A/B, TRB-29A, C-97, YC-97, Lockheed C-121A, VC-121B, and Consolidated Vultee B-32. Other models of the R-3350 powered the Martin PB2M Mars flying boat, and continued to serve commercial aviation long after the war.

Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Object Details
Date October 4, 1944 Country of Origin United States of America Type PROPULSION-Reciprocating & Rotary Manufacturer Dodge (Wright)
Designer Wright Aeronautical
Physical Description Type: Reciprocating, 18 cylinders, 2-rows, geared, radial, air-cooled Power rating: 1,641 kW (2,200 hp) at 2,800 rpm Displacement: 54.9 L (3,347 cu in.) Bore and Stroke: 156 mm (6.125 in.) x 160 mm (6.3125 in.) Weight: 1,251 kg (2,757 lb) Dimensions Diameter 140 cm (55.13 in.), Length 194 cm (76.25 in.)
Inventory Number A19670019000 Credit Line Found in the collection Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
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