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.