The Dewoitine D.520 was a French fighter aircraft that entered service in early 1940, shortly after the opening of World War II. Unlike the Morane-Saulnier M.S.406, which was at that time the Armée de l'Air's most numerous fighter, the Dewoitine D.520 came close to being a match for the latest German types, such as the Messerschmitt Bf 109. It was slower than the Bf 109E but superior in manoeuvrability. Because of a delayed production cycle, only a small number were available for combat with the Luftwaffe.
The Groupe de Chasse I/3 was the first unit to get the D.520, receiving its first aircraft in January 1940. These were unarmed and used for pilot training. In April and May 1940, operational units received 34 production D.520s; the type proving to be very popular with the pilots. By 10 May 1940, when Germany invaded France and the Low Countries, 228 D.520s had been manufactured, but the Armée de l'Air had only accepted 75, as most others had been sent back to the factory to be retrofitted. By the armistice at the end of June 1940, 437 D.520s had been built with 351 delivered.
During the liberation of France, a few D.520s abandoned by the Germans were used by ad hoc units in ground attacks against the isolated German pockets of resistance on the Western coast.
