The Potez 39 was designed to a 1928 requirement for an aircraft to replace the Potez 25 and Breguet 19 machines then in service with the French Air Force in the A2 (Artillerie Biplace – two seat observation aircraft) role. The Potez 37 and Potez 39 appeared in 1930.
Both were two-seat braced parasol-wing monoplanes of all-metal construction, the former being intended for the fighter-reconnaissance role and having a rear fuselage which tapered into little more than a boom to give the gunner an improved field of fire. The prototype Potez 39 was designed for A.2 category observation role, and had a conventional fuselage and redesigned wings with elliptical tips. The Potez 37 was rejected for production, only two examples being built, but the Potez 39 showed great promise and was adopted by the Armee de I’Air.
The Potez 39 was a parasol monoplane of all-metal construction, the first all metal Potez aircraft, with a tailwheel undercarriage. It was powered by a Hispano-Suiza 12H engine of 580 bhp (433 kW) as required by the specification. The crew of two sat in open, tandem cockpits, with the observer being armed with two Lewis guns on a ring mounting, and the pilot being armed with a single synchronised Darne machine gun, while light bombs could be carried in a small internal bomb-bay and on external racks. A fixed camera was fitted, operating through a hatch in the fuselage floor. The prototype flew in January 1930. Although the Breguet 27 was selected as the winner of the competition, both it and the Potez, which was runner-up, were chosen for production.
Compared to the Potez 25, of which over 2000 were ordered, production of the Potez 39 series was on a small scale, 100 Potez 390 aircraft being built for France and 12 Potez 391 variants, powered by a Lorraine-Dietrich 12H engine of 700 bhp, for the Peruvian Air Force.
The first production aircraft were delivered in 1934 but shortly afterwards, the Potez 39 began to be replaced by ANF Les Mureaux 117, Amiot 143 and Potez 540 aircraft ( in 1936).
Series Potez 390 and Potez 391 aircraft were subjected to various modifications during production and service, notably the introduction of a rudder with increased area, but they retained the basic features of the design, which included a divided fixed wide-track landing gear with wheel spats; streamlined Vee-struts supporting the wings; and glazed panels in the fuselage sides between the cockpits.
The Armee de I’Air received 232 P-390s and P-391s, the first unit to re-equip in early 1934 being the 34e Escadre, where they replaced Potez 25s. At the outbreak of the Second World War the Potez 39 remained in service with seven observation squadrons of the French Air Force, but these, along with the Breguet 27-equipped units, were withdrawn from the front in October 1939. The Potez 39 continued to serve in training units until the armistice of June 1940, at which time 41 remained in Metropolitan France. These aircraft were scrapped soon afterwards.
A number of prototype and development aircraft, including a floatplane, were tested but no further orders were received.
In early 1938, the Ilmavoimat / Maavoimat test team evaluated the Potez 39. Given that the aircraft was already being replaced in service in France, the evaluation was cursory and simply confirmed that the aircraft was obsolete and should not be considered further.
Potez 390 A.2
Engine: 1 x Hispano-Suiza 12Hb, 433kW
Max take-off weight: 2650 kg / 5842 lb
Loaded weight: 1492 kg / 3289 lb
Wingspan: 16.0 m / 53 ft 6 in
Length: 10.0 m / 33 ft 10 in
Height: 3.40 m / 11 ft 2 in
Wing area: 35.0 sq.m / 376.74 sq ft
Max. speed: 240 km/h / 149 mph
Ceiling: 7000 m / 22950 ft
Range: 700 km / 435 miles
Armament: 1 x 7.7mm + 2 x 7.7mm machine-guns
Bomb load: 120kg
Crew: 2
All Aero 