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POTEZ 620

 


Technical Specifications
Type
Transport Aircraft
Date first flight
January 28,1935
Wingspan
22,45
Lenght
17,32
Height
3,90
Wing Area
40,20 m2 
Empty Weight
4895 Kg 
Max. Takeoff Weight
7500 Kg 
Cruising Speed
280 km/h. 
Maximum Speed
325 km/h
Climbing Speed
Service ceilling
740 0 m 
Range
1000 kms
Crew
3 Men
Motorization
2 Engines Gnôme Rhône 14Kirs of 820 Hp each
Armament
14 / 16 Passengers

 


Production

23 Potez 620 and 621 were built since the date of the first flight on January 28, 1935.

To date, of the 23 aircrafts manufactured, 23 are listed in the list below :


Historical

In 1933, the brand new Air France company needs to renew its aircraft fleet. The promising Bloch MB220 and Dewoitine D338 are not yet available, so the company is turning to transient aircrafts like the Wibault 283T.

It is in this context that the Potez company offers Air France the Potez 620. This is derived from its twin-engines Potez 540 that responds to the B.C.R program (Bombardment / Combat / Reconnaissance). This twin-engine, appreciated for its flight capabilities and maneuverability, however, has average performance.

Potez 62 takes back the wing of Potez 540. It's metallic structure is built around two central rails in Duralumin, without shutters, any covered by a canvas covering in linen. The engine nacelles and the retractable landing gear are very close to those of the Potez 540. It is powered by two Gnome-Rhone radial 14Kdrs / Kgrs of 14 cyl of 850 HP at the takeoff leading to three-blade metal propellers with fixed pitch. The fuselage is made of wood and is divided into several parts: the two-seater cockpit, the toilet and the steward's post. Then comes a cabin for 6 passengers and a second for 8 passengers. At the rear of the aircraft, there is a luggage compartment. The aircraft is comfortable: it is indeed equipped with heating and good soundproofing.

On September 12, 1934, Air France ordered 6 aircraft to the company Potez, the first to be delivered from December 1, 1934 and the last before June 1, 1935. Following changes requested by Air France, it is only the 28 January 1935 that the Potez 662 made its first flight. The tests are going well, and registered F-ANPG, it is delivered to the Air France Company in April 1935, quickly joined by the 2nd aircraft registered F-ANPH with a first commercial flight on the Line Le Bourget-Marseille May 22, 1935 Meanwhile, Air France confirms an order for 12 aircraft.

Reliability issues are rapidly emerging due to poor cooling and poor quality of the Gnome-Rhone 14K engines. Thus, on December 10, 1935, the F-ANPH caught in a snowstorm, sees his left engine stop after a drop in oil pressure. The plane crashes near Auxerre: even if we only deplore the wounded, this event nailed to the ground all Potez 620 until January 1936. The engines Gnome-Rhone 14K are replaced on the n ° 8 by Hispano-Suiza 12X engines, 12 cylinders in V 720 cv driving three-blade metal propellers with variable pitch: thus motorized, it makes its first flight on November 15, 1935. The following aircraft will be modified in this way and will take the name Potez 621.

Thus motorized, from May 1936, the Potez 621 is put into service on the section Buenos Aires - Santiago de Chile. Two planes (F-ANQN "Aguila", and F-ANQQ "Falcon") will regularly ensure this connection until the armistice of June 25, 1940. If the trace of "Falcon" disappears at this time, "the Aguila ", stored first in Buenos Aires will be sold in March 1942 to the new Uruguayan company Pluna. It will provide services between Montevideo and Buenos Aires, until 1946, before being stored, then destroyed in 1947.

From the declaration of war, in September 1939, nine Potez 620/621 of Air France are requisitioned. They will be assigned to Transport Aircraft Sections (SAT) 8/110 and 9/110, based at Le Bourget. During the winter of 1939/40, these aircraft were integrated into a plan for troop transport to Holland in the event of a German invasion by that country. Finally, the plan is abandoned, and the Potez 620/21 resume their mission links.
After the German attack of May 10, 1940, they are used especially for the transport of the personnel and the equipment of the Hunting Groups, which must frequently change lands, pushed by the German advance. However, these devices, outdated and lacking spare parts, are frequently unavailable.
At the Armistice, the transport units are dissolved, and the Potez 620/621 are retransferred to Air France, although the flights are not yet authorized.

Free France recovers damaged, the Potez 621 F-ANQS, ex Air France on the ground of Damascus. Rehabilitated and re-registered "OD-AAJ", it is made available to the Governor of the Levant, Lebanon.

Air France will finally receive 8 Potez 620 and 15 Potez 621, including 6 in long-haul version.


Versions

Versions
Qty
Descriptive
Potez 620
8
Motorized version by radial Gnome-Rhone 14Kdrs / Kgrs, then 14Kirs / Kjrs, and finally 14N16 / 17, 14 cylinders, 850 hp (830 hp) driving three-blade metal propellers with fixed pitch (not variable with 14N). Equipped for 14 to 16 passengers on short and medium-haul lines.
Potez 621
15
Following engine reliability problems encountered on the Potez 620, this version is powered by Hispano-Suiza 12Xgrs / hrs 12-cylinder V, developing 720 horses at 2100 m. They cause three-blade metal propellers with variable pitch. The first Potez 621 was actually the Potez 620 n ° 8 F-ANQN "Flamant" delivered October 15, 1935. With this new engine, he made his first flight on November 15, 1935.

 


Bibliography

Document Air No2:
- Potez Types 62 et 65 par Pierre Dumollard

 


Photos Album

 


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