The D.500 and D.501 entered service in July 1935, with the more powerful
D.510 joining them in October 1936. They were the primary fighters employed by the Armée
de l'Air until replacement by the Morane-Saulnier M.S.406 in 1939. As of September 1939,
the D.500/501 had been relegated to regional defense and training squadrons. At the start of
World War II, D.510s were still in operation with three Groupes de Chasse (Fighter
Groups), two Escadrilles Régionale de Chasse (Regional Fighter Squadrons in North
Africa), and two Escadrilles de Aéronautique Navale (Naval Aviation Squadrons).
In Morocco, one escadrille of D.510s (ERC571) was activated in November,
1939. These planes lacked cannon. In May of 1940, this escadrille merged with ERC 573 to
form GC III/4. This groupe was disbanded by the end of August, 1940. At Dakar, one groupe
designated GC I/6, remained in service until being replaced by Curtiss H-75s at the end of
1941.
Seven D.500s originally sold to Lithuania and two D.510s ostensibly intended
for the Emirate of Hedjaz saw service in the Spanish Civil War, arriving in mid-1936. When
the French government found out about the delivery of D.510s, they demanded return of the
12Y engines. The aircraft were then refitted with Klimov M-100s (a Soviet-built copy of
12Y) from a Tupolev SB bomber. The aircraft served with the Republican forces. The
two 510s were posted to the 71st Coastal Defense Group. Neither engaged enemy fighters. In
1938, one was irreparably damaged while landing and the other was destroyed on a runway
during a bombing attack.
In
1938, 18 Chinese D.510s saw action against the Japanese, including the defense of Chengdu
and Chinese wartime capital Chougqing.
