The only American liquid-cooled engine put into mass production during the Second World War, the Allison V-1710 is most closely associated with the Curtiss-Wright P-40 Warhawk. Initially developed as a possible engine for U.S. Navy dirigibles, the loss of the U.S.S. Macon killed the project and sent the company into decline. Eventually purchased by General Motors, GM put funds into the design.
A sturdy and reliable engine, its main drawback was a lack of performance at high altitude. Allison engineers solved the problem by turbosupercharging. The lack of wartime capacity to create key parts – notably those requiring tungsten – limited turbosuperchargers to bombers and certain other designs. A few turbosupercharged V-1710s were produced, prompting P-40 designer Donald Berlin to brag that the experimental P-40s with the high-altitude package outperformed Spitfires and Messerschmitts.
Without the turbosupercharger, the 14,000 P-40s produced an admirable war record. The same cannot be said for the other major V-1710 powered airframe, the ill-fated P-39 Aircobra. Without the extra power, the P-39 was sluggish.
Perhaps the best mating of turbine and V-1710 was the P-38 Lightning. The twin-engined fighter became the dominant plane wherever it was employed during the Second World War thanks to its speed and power. In the photograph, there is a work-stand mounted turbocharger just behind the V-1710.
There is no better argument for what the airframe means to the success of an engine than the P-39 and P-40. The P-40 was extremely successful with the American Volunteer Group and was the early war backbone of the USAAF. The P-39, with its unique design, saw some success as a Lend-Lease aircraft to the Soviets. With the engine buried behind the cockpit to allow the placement of a 20mm cannon in the nose, it became a good ground support platform but a poor fighter.
The V-1710 went on to a considerable post-war career as a favorite of the Unlimited Class racing aircraft, as well as in other speed applications such as hydroplanes and unusual automobiles.