The prototype Potez 62 civil airliner, based on the military Potez 54, made its maiden flight on 28 January 1935. It retained the strut-braced high-set wing of the Potez 54, which was married to a redesigned fuselage. Pilot and co-pilot were seated side-by-side in a control cabin with, to their rear, two cabins accommodating up to 16 passengers. Undercarriage was retracting, but there were no flaps, which the large wing area with thick airfoil made unnecessary, at the expense of speed.
The wooden fuselage had a composite coating, whereas the wings were covered with fabric and the leading edge was made out of metal. The aircraft was propelled by two Gnôme & Rhône radial engines whose 14 cylinders produced some 870 hp. The engines were mounted in two side cradles, fixed to the fuselage and to the wings.
The Potez 621 ordered by Air France, flown later in 1935, introduced 537kW Hispano-Suiza 12Xrs Vee engines and 2 degrees sweepback on the wings. These were used on routes inside South America. By late 1936, many Potez 62s were employed on routes to Europe and the Far East, as the aircraft was robust and reliable, albeit slow. It remained in service until the Second World War, and one was used by the Free French Air Force.
Production totalled 23, four of the 14 machines built as Potez 62s later being converted to Potez 621 standard, and in 1937 nine Potez 62s were re-engined with 671kW Gnome-Rhone 14N16/17 radials.
The type interested the Armee de I’Air, which ordered a troop transport version, the Potez 65 or Potez 650 TT, which had accommodation for a crew of three plus 14 fully-equipped troops or, if equipped as an ambulance, with provision for six stretchers, four seated patients and one medical attendant.
The Potez 650 only received relatively minor modifications: Hispano-Suiza 12X liquid-cooled inline engines instead of the Gnome-Rhône 14K radials, a less sophisticated cabin with accommodation for 14 paratroopers and their equipment (one squad) or 10 wounded (for the medevac role), and a larger door system for bulky loading (transport role). The first paradrop from a Potez 650 occurred on May 1937.
Two orders totalling 15 aircraft were received by Potez, the first of them being delivered in late 1935. Powered by 537kW Hispano-Suiza 12 Xirs I or HS 12Xbrs l/grs I engines, and with a maximum take-off weight higher than that of the Potez 62, the military version had maximum speed reduced to 300km/h.
The French military high-command did not have grandiose plans for paratroopers, which did not fit well with its essentially defensive doctrine of the pre-World War II era. Because of this, only two paratrooper companies were formed, and never reached full theoretical strength, and only 15 Potez 650s were manufactured. They were not sufficient in numbers even for such a small number of men, so the big Farman 224 airliner which had just been refused by Air France was pressed into military service.
A combat mission was planned as part of the Allied entry in the Netherlands in the case of a German attack, but the plan was cancelled, and eventually no combat paradrops took place in 1939-1940.
After the armistice, paratrooper units were officially disbanded, although training jumps were performed from time to time in North Africa. The Potez 650s were transferred to a military transport unit. When Free French and British forces attacked the French protectorates of Syria and Lebanon in mid-1941, the Vichy government established an airbridge to resupply its troops in the middle east. Potez 650s took a significant share of the work, alongside converted bombers (Farman 223.3s) and airliners (Dewoitine 338s).
In 1937, the Romanians acquired one civil Potez 62, which was operated until 1944. In late 1936, the Romanian Air Force expressed interest in acquiring foreign military aircraft. The Potez 650 was selected, but Romania required Gnome-Rhône 14K engines to be fitted like originally on the Potez 62, since a license to manufacture these engines had already been acquired by Industria Aeronautică Română. Six examples of this new variant, designated Potez 651 were ordered in 1937, although it seems only four were operationally used. These aircraft were actively involved at the initial stage of the war against the Soviet Union in 1941-1942. Originally ordered as bombers, the Romanian Potez 651s were relegated to transport duties during World War II. Three examples were still in service in May 1944.
Operators were Air France, the Free French Air Force, and LARES of Romania.
Potez 62
Engines: 2 x Gnome-Rhone 14Kirs Mistral Major, 870 hp / 649kW
Wingspan: 22.45 m / 74 ft 8 in
Wing area: 76.0 sq.m / 818.06 sq ft
Length: 17.32 m / 57 ft 10 in
Height: 3.9 m / 13 ft 10 in
Max take-off weight: 7500 kg / 16535 lb
Empty weight: 4,000 kg (8,800 lb)
Loaded weight: 4895 kg / 10792 lb
Max. speed: 325 km/h / 202 mph
Cruise speed: 280 km/h (151 knots, 174 mph) at 2,000 m (7,500 ft)
Service ceiling: 7500 m / 24600 ft
Range: 1000 km / 621 miles / 540 nmi
Crew: 3
Capacity: 14-16 passengers
Potez 620
Engines: 2 x PD Gnome-Rhone 14Kirs, 820 hp
Wingspan: 22.45 m
Wing area: 76.00 sq.m
Length: 17.32 m
Height: 3.90 m
Empty weight: 4895 kg
Normal takeoff weight: 7500 kg
Maximum speed: 325 km / h
Cruising speed: 280 km / h
Practical range: 1000 km
Service ceiling: 7400 m
Crew: 2
Payload: 16 passengers
Potez 650
Engines: 1 × Hispano-Suiza 12Xgrs1 liquid-cooled V-12 piston engine, 540 kW (720 hp) (right hand rotation)
1 × Hispano-Suiza 12Xhrs1 liquid-cooled V-12 piston engine, 540 kW (720 hp) (left hand rotation)
Wingspan: 22.45 m (73 ft 8 in)
Wing area: 76 sq.m (820 sq ft)
Length: 17.32 m (56 ft 10 in)
Height: 3.9 m (12 ft 10 in)
Max takeoff weight: 7,500 kg (16,535 lb)
Empty weight: 4,632 kg (10,212 lb)
Maximum speed: 300 km/h (186 mph; 162 kn) at 2,000 m (6,600 ft)
Cruising speed: 250 km/h (155 mph; 135 kn) at 2,000 m (6,600 ft)
Range: 1,200 km (746 mi; 648 nmi)
