The Potez 630 was a twin-engined fighter powered by troublesome Hispano-Suiza engines and that was produced in small numbers to make up for slow production of the more reliable Gnome-Rhone powered Potez 631.
The Potez 63 family was developed in response to a specification issued in 31 October 1934 calling for a two or three seat multipurpose fighter. Potez responded with two versions of the same basic design. The Potez 630 was to be powered by two Hispano-Suiza 14Hbs engines, while the Potex 631 used Gnome-Rhone radials. Both aircraft were low-wing twin-engined monoplanes with a pronounced resemblance to the Messerschmitt Bf 110.
Potez were asked to produce a prototype of the Potez 630 at their own expense. Work on the Potez 630-01 began in April 1935, and the prototype made its maiden flight on 25 April 1936. At this point it was powered by two 580hp Hispano-Suiza 14Hbs engines while the tail had a braced wooden horizontal stabilizer, with no dihedral. The aircraft was delivered to Villacoublay for official trials on 3 August 1936, where it received a new metal horizontal stabiliser, with dihedral, as well as new landing gear. Official trials began at the end of August, and the prototype was then sent to Cazaux for armament tests. In trials the Potez 630 was shown to be highly manoeuvrable, but even when it was given 700hp 14AB engines it could only reach 282mph.
At the end of 1936 Potez was nationalised, becoming part of SNCAN (National Aircraft Construction Company of the North). Early in 1937 the newly nationalised concern was issued with an order to produce ten evaluation aircraft, including four Potez 630s. If enough Gnome-Rhone engines had available then the Potez 630 may never have entered production, but this wasn't the case, and in letters of intent issued in June 1937 SNCAN were ordered to build 80 Potez 630s and only 40 Potez 631s. This was the only French order to be placed for the Potez 630, and it was not a great success on the export market either, with one ordered by Switzerland and two by Yugoslavia.
A total of 88 Potez 630s were built - the prototype, the four evaluation aircraft, the 80 production aircraft and the three export aircraft. 85 of these aircraft were accepted by the Armée de l'Air, the prototype entered civil service and two were exported. The first of the production aircraft made its maiden flight in February 1938, and the Armée de l'Air accepted delivery of its first four aircraft in May 1938 (although the first official 'acceptance' didn't come until August). Production was somewhat delayed by a shortage of 20mm cannon, and so the first batch of aircraft were armed with four machine guns in the nose in place of the cannon. Forty-five had been accepted by 1 January 1939, 77 by 1 April and all 85 by August, by which date 65 aircraft were with operational units.
The Potez 630 began to enter service in September 1938 when seventeen aircraft were allocated to the Rheims, Dijon, Etampes and Chartres Escadres de Chasse. The idea was that these aircraft would serve as airborne fighter directors, controlling the operations of large numbers of single engined fighters. Eventually each Escadres de Chasse operating single-engined fighters were given six Potez 63 series fighters, either Potez 630s or Potez 631, although these wings were disbanded before the start of the German offensive in the west.
The Potez 630 was also briefly used to equip two night fighter groups, Groupes de Chasse de Nuit GCN III/1 and II/4 (renumbered as I/13 and II.13 in May 1938), replacing the obsolete Mureaux 113. Both units quickly converted to the Potez 631.
At the start of the Second World War sixty five Potez 630s were in use with first-line units, ten in Tunisia and the remaining fifty five operating with the fighter direction wings. After the outbreak of war two Potez 630s were amongst twelve aircraft that were taken from existing units to form a 5th Escadrille within G.C. II/2, Escadrille de Guet I/16 (warning unit). This was a short-lived designation, and on 29 January 1940 it was redesignated as E.C.M. I/16 (Escadrille de Chasse Multiplace).
Soon after this the problems with the Hispano-Suiza engines (and the difficulties of operating aircraft with different engines in the same units) convinced the Armée de l'Air to withdraw the Potez 630 from front line service. At the same time the fighter direction flights were scrapped. The remaining Potez 630s were turned into dual control trainers, and used to give new crews experience on modern twin-engined aircraft while they waited for their Breguet 691s and 693s to arrive.
Engine: Hispano Suiza 14 AB 10/11 engines
Power: 590hp at sea level, 670hp at 13,123ft, 650hp at take off
Crew: 2 or 3
Wing span: 52ft 6in
Length: 36ft 4in
Height: 11ft 10 1/2in
Empty Weight: 6190.5lb
Loaded Weight: 8487.7lb
Max Speed: 278mph at 13,123ft
Range: 807 miles
Armament: Two forward firing 20mm cannon, one flexibly mounted rear firing 7.5mm machine gun