The most advanced French fighter in service during 1938 with the Armée de l’Air was the Dewoitine D.510. As the final version of an original design that first flew in service during 1934, the D.510 was equipped with an Hispano-Suiza 12Ycrs liquid-cooled 12-cylinder engine. The fighter had a top speed of 244 mph at 16,405 feet. Armament was two 7.5mm MAC 1934 machine guns in the wings, plus one 20 mm Hispano-Suiza HS.9 cannon firing through the hub of the three-bladed metal propeller. With a 91-gallon fuel tank capacity, the 860hp engine managed a maximum range of 435 miles.