The BMW 803 is a six-cylinder aircraft engine developed by the German company BMW during the late 1930s. It was designed for use in various military aircraft, providing reliable performance and power. The engine features a liquid-cooled configuration and was known for its smooth operation and efficiency. With a displacement of 800 cubic centimeters, the BMW 803 produced around 800 horsepower. It was primarily used in the Messerschmitt Bf 109 and other aircraft, contributing to the performance of these notable World War II fighters. The engine's design and engineering reflected the advanced technology of its time.