Wright Turbo-Cyclone 18R-3350-TC Radial Engine


Display Status:

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

Collection Item Summary:

This engine powered the last generation of piston engine transports, including the Douglas DC-7 and Lockheed Super Constellation. It represents the end of engine-development that began with the famous Wright Whirlwind, and included an entire family of military and commercial piston power plants. The somewhat unique feature of this engine was a turbo compound device, consisting of an exhaust-driven turbine geared to the crankshaft, generating 20 percent additional take-off power without increasing fuel consumption.

The Wright R-3350 Turbo-Cyclone 18 also powered the following aircraft types: Lockheed P2V-7 Neptune patrol bomber, Martin P5M-1 and -2 Marlin patrol flying boat, Fairchild C-119F and G Packet troop and cargo transport, Lockheed C-121 transport, and Canadair CL-28 maritime reconnaissance.

This artifact powered the American Airlines Douglas DC-7C "Flagship Vermont." A total of 374 engines of this model were built between August 1952 and December 1954. A total of 5,656 commercial C18 and 44,536 military R-3350 engines were manufactured.

Collection Item Long Description:



Inventory Number


Physical Description

  • Type: Reciprocating, 18 cylinders, 2 rows, radial, air-cooled
  • Power rating: 2,424 kW (3,250 hp) at 2,900 rpm
  • Displacement: 54.9 L (3,350 cu in.)
  • Bore and Stroke: 156 mm (6.1 in.) x 160 mm (6.3 in.)
  • Weight: 1621 kg (3573 lb)

Credit Line

Gift of American Airlines, Inc.


Country of Origin

United States of America


Engine Overall - Steel, Aluminum, Inconel X


  • 3-D: 233.2 × 143.8cm, 1620.7kg (91 13/16 × 56 5/8 in., 3573lb.)
  • Support: 280.7 × 158.8 × 188.6cm (110 1/2 in. × 62 1/2 in. × 74 1/4 in.)

Data Source

National Air and Space Museum

Restrictions & Rights

Do not reproduce without permission from the Smithsonian Institution, National Air and Space Museum


PROPULSION-Reciprocating & Rotary