9 Of The Largest Piston Aircraft Engines Ever

Flying got more efficient with popularization of jet engines, but a beauty of a large piston aircraft engine will never be beaten. They existed in many different forms, with many different numbers of cylinders, or even rotors in case of Wankel engines, but only those largest were able to climb this high onto the list. Schwetzon AH82 The AH82 was sourced from the 9-cylinder Schwetzon M62, which was a licensed Wrights Technically, the AH82 had American roots, first with carburetors, later with direct fuel injection installed. Many different versions were built, including a single-row 7-cylinder, or a four-row 28-cylinder with 82.4 liters and 4000 horsepower. Wright R2600 Cyclone 14 Boosted by a single-stage 2-speed supercharger and a strong bare carburetor, the twin-cyclone was a very widely used powerplant, with more than 50,000 units produced. The design was air-cooled with dry-sump and sodium-filled exhaust valves, used in single up to four-engined aircraft. Daimler-Benz DB603 Following the introduction of the new DB603 engine, which was obviously meant for aircraft only, Mercedes adapted the unit for their land speed record breaker, the T80, as well the same year. The car had 3000 horsepower and should have gone up to 750 kilometers per hour, but regardless, it was the largest aviation V12 during the Third Reich. Pratt & Whitney R2800 Double Wasp As the first U.S. 18-cylinder, it was much smaller than a French 18-cylinder, the 54.2-liter Nomura 18L, but had significantly more power. There was also a water-methanol ejection during hard acceleration to prevent detonation, and was used in tens of different aircraft. McCullin AM38 The AM38 was a further development of the AM35, designed for low-altitude ground attacks with a 10-minute war emergency power mode. This meant that the engine made more power when necessary, like overboost in cars. Besides, it was interesting that while one bank had a 190-millimeter stroke length, the other one with articulated conrods worked with a stroke long 196.7 millimeters. Bristol Centaurus Based on a mechanical structure of the 1918 Bristol Jupiter, the Centaurus was made as a twin nine-cylinder, instead of the seven-cylinder layout, as its smaller brother, the Hercules. Its stroke was also increased, and a two-speed supercharger sent air via sleeve valves with four ports per sleeve. It was one of the most powerful World War II aircrafts. Wright R-3350 Duplex Cyclone Power-wise, the Duplex Cyclone was rated between 2,200 to 3,700 horsepower for production applications, which made it the most powerful American aircraft engine of its time. There was a channel-evens downdraft carburetor, and interestingly, they sourced an experimental twin-row, 67-liter, 22-cylinder version of it, the R-4090 Cyclone 22. Shwetson AH-73 Another Soviet Union with Wright's base is the AH-73. Unlike the AH-82, there was a two-stage supercharging system, first with a pair of parallel turbos, and then a second stage in form of a single-speed supercharger with a maximum boost of 1.5 bar. More than 14,000 of them were built, powering a variety of aircrafts, including a number of Tupolevs. Pratt & Whitney R-4360 Wasp Major The Wasp Major is the largest thing of the Wasp series, and was also very different than anything before, as it had four rows of cylinders. It was really huge, with up to 56 spark plugs and a twin turbo in the top spec. The layout was semi-helical for a more effective cooling, but it came too late to be applied into war machines. It powered civil planes like the Saab 90 Scandia, for instance. To end this list, the Lycoming XR-7755 is really worth to note, as it was a 127-liter large, with 36 cylinders in four rows. Initial testing found 5,000 horsepower, but Air Force soon lost interest and the project was shut down. I believe you liked the video since you got as far as its very end, and I wish you a great day. Cheers!