MOC-178855+MOC-178952 XR-7755-3 36-Cylinder Piston Aviation Engine Building Blocks Set with Stand (1559PCS)

Material: ABS 1.Background: The XR-7755-3 is the world's largest and most powerful reciprocating aircraft engine. During World War II, the U.S. Army Air Corps required an engine with high takeoff power and low fuel consumption for long-range bombers and transports that had not yet been designed. Lycoming began designing the engine in early 1944 and had it ready for testing by mid 1946. It featured nine two-lobe overhead camshafts, which could be moved axially to improve takeoff and cruise efficiency, and a two-speed, geared, double-rotating propeller drive. It was originally intended for use in the “European Bomber”, which eventually became the Convair B-36. The program was terminated in 1946, and only two were built, the last of which appears to be on display at the Smithsonian Air and Space Museum! 2.Design: The design utilized nine four-cylinder engines, each group of four cylinders arranged at a 40° angle to adjacent cylinders and arranged around a central crankshaft to form four r