Potez 630

https://en.wikipedia.org/wiki/Potez_630

The Potez 630 and its derivatives were a family of twin-engined aircraft
developed for the French Air Force in the late 1930s. The design was a
contemporary of the British Bristol Blenheim (which was larger and designed
purely as a bomber) and the German Messerschmitt Bf 110 (which was designed
purely as a fighter).

The Potez 630 was in use by several operators during the Second World War.
Following the Battle of France, both the Vichy French Air Force and Free French
Air Forces used the type; a number of captured aircraft were operated by several
air wings of the Axis powers. After the end of the conflict in 1945, a handful
of aircraft were used for training purposes for some time.

Origins

On 31 October 1934, the French Ministry of Air issued a specification for a
heavy fighter. The specification demanded the aircraft be capable of performing
three principal roles: fighter direction, in which it was required to lead
formations of single-engine fighters with sufficient maneuverability; day
attack, in which the type was also to escort friendly close air support and
bomber aircraft; and nightfighter operations. Specified performance details
included a maximum speed of 450 km/h at 4,000 meters, a 300 km/h cruising speed,
and an endurance of at least four hours. Armament requirements included two
fixed forward-firing 20 mm cannons and a single machine gun to the rear for
self-defence. The sought aircraft was also required to accommodate two/three
seats along with a twin-engine configuration; however, some of the performance
limitations imposed upon the aircraft, such as the maximum weight, served to
restrict the range of suitable engines to power the type.

The original Potez 630 was developed to meet this specification; two variants of
the aircraft were originally submitted for consideration, one (the 630) powered
by Hispano-Suiza 14AA radial engines and the other (the 631) with the
Gnome-Rhône 14N. Other companies also produced submissions in response,
including Breguet Aviation, Hanriot, Chantiers aéronavals Étienne Romano, and
Loire-Nieuport. Each of the competing manufacturers were requested to produce a
single prototype for evaluation at their own expense; work on the first
prototype, designated as the Potez 630-01, commenced in April 1935. In addition
to the Potez 630, the same specification had ultimately resulted in the
successful Breguet 690 series of attack aircraft.

The Potez 630 was a twin engine, monoplane, fully metallic three-seater with
efficient aerodynamic lines and twin tailplanes. The basic design allowed for
the type to replace various obsolete aircraft in the French Air Force in a wide
range of roles. The long glasshouse housed a crew of three, comprising a pilot,
an observer or commander who was carried based upon mission requirements, and a
rear gunner who manned a single flexible light machine gun. The Potez 637
featured a glazed gondola located beneath the fuselage for an observer to be
carried in the prone position. Some variants, such as the Potez 631 and 633, had
a vertical bomb bay located between the two crew members. The 630 was a
relatively simple and sound design, requiring an average of 7,500 man-hours to
assemble each aircraft.

All members of the family (with the possible exception of the Potez 63.11)
shared pleasant flying characteristics and were designed to allow for easy
maintenance.

As a daytime fighter aircraft, the performance of the Potez 631 C3 was
relatively disappointing, partially due to a low maximum speed and inadequate
rate of climb compared with contemporary fighter aircraft. When applied to the
nightfighter role, their lack of detection capability against enemy aircraft
rendered their presence mainly ineffective. Later models had a heavy armament
(12 machine guns for the Potez 63.11). Unfortunately the Potez 63 family, like
many French aircraft of the time, simply did not have sufficiently powerful
engines to endow them with an adequate performance and they proved vulnerable to
Messerschmitt Bf 109s, like the contemporary Fairey Battle and Bristol Blenheim
bombers. Their similarity to the Messerschmitt Bf 110, both being equipped with
twin engines, twin fins and a long greenhouse canopy, is believed to have
resulted in several aircraft being lost to "friendly fire".


Role
Heavy fighter

Manufacturer
SNCAN

Designer
Louis Coroller and André Delaruelle

First flight
25 April 1936

Introduction
October 1938

Status
Retired

Primary users
French Air Force
French Naval Aviation
Vichy French Air Force
Free French Air Forces

Number built
1,395

From May 1938, production Potez 630 fighters started to be delivered; the first
improved Potez 631 aircraft were received in August that year. Potez 630 and
631s, in two-seater configuration, were soon used to replace obsolete ANF Les
Mureaux 113 used as night fighters, while single-seat fighter groups received a
number of three seat Potez 63s to act as command aircraft, from which formations
of single-seat fighters would be directed and co-ordinated by radio. In July
1938, the first fifteen Potez 630 aircraft participated in the Villacoublay Air
Show.

By September 1938, the Potez 630 had begun to supplant the obsolete Bloch MB.200
bomber in the fighter direction role; however, the Potez 630's engines proved so
troublesome in service that most units were rapidly re-equipped with the Potez
631 prior to the outbreak of the Second World War. By 1 April 1939, a total of
77 Potez 630 and 88 Potez 631 aircraft had been accepted by the French Air
Force. The retirement of other obsolete French aircraft, such as the
Morane-Saulnier M.S.225 and Dewoitine D.510, could be accommodated for by the
increasing numbers of Potez 631s. Just prior to the outbreak of the Second World
War, the French Air Force had 85 Potez 630s, 206 Potez 631s, 22 Potez 633s, 63
Potez 633s, and 5 Potez 63.11 aircraft.

The Potez 633 aircraft that were exported to Greece and Romania saw greater
service than their French counterparts despite their limited numbers. Greece had
nine Potez 633s in service when Italy invaded Greece in October 1940. These were
used for bombing attacks against Italian supply lines until shortage of spares
forced their withdrawal. In June 1941, Romania joined Germany in the invasion of
the Soviet Union. Two squadrons were equipped with the Potez 633 which were used
to support the Romanian army as it advanced towards Odessa. In 1942, they were
replaced by Junkers Ju 88 bombers, allowing the survivors to be transferred to
the advanced training role.

At one point, the Potez 637 was the only modern aircraft equipping the Groupes
de Reconnaissance (GOA), which had long been equipped with obsolete aircraft.
From November 1939 onwards, the first units to convert to the Potez P.63.11 were
each assigned three aircraft. By mid-January 1940, there were 43 Potez 63.11s in
service with 12 GOAs. By June 1940, more than 700 reconnaissance Potez 63.11 had
been delivered. These aircraft encountered various fates in service: more than
220 were destroyed or abandoned. Despite the addition of extra machine gun
armament, aircraft having received either six, eight, or ten machine guns, the
Potez 63.11 suffered the heaviest losses of any French type. One factor
contributing to the high losses was the near-complete lack of spares, rendering
70 per of all P.63.11 aircraft unserviceable even prior to the German invasion;
many aircraft were destroyed on the ground by enemy bombing and strafing
attacks, and entire units were wiped out without conducting a single mission.

On 27 November 1942, German military units occupied Vichy Air Force bases and
seized their aircraft: around 134 Potez 630s of several variants were taken. Of
the seized aircraft, 53 were refurbished and dispatched to Romania for use as
trainers and target tugs; spare engines were also reused to power a number of
Luftwaffe Henschel Hs 129Bs. Production of the type was resumed under German
control; significant numbers of aircraft appear to have been pressed into
service by the Germans, mostly in liaison and training roles. The last three
Potez 631s in service were recaptured examples; these made a final contribution
following the cessation of hostilities in their use as trainer aircraft at the
Centre d'Essais en Vol for the revived French Air Force.

Specifications (Potez 63.11A.3)

General characteristics
Crew: three
Length: 10.93 m (35 ft 10?1/3 in)
Wingspan: 16.00 m (52 ft 6 in)
Height: 3.08 m (10 ft 1?1/4 in)
Wing area: 32.7 m² (352 ft²)
Empty weight: 3,135 kg (6,911 lb)
Max. takeoff weight: 4,530 kg (9,987 lb)
Powerplant: 2 × Gnome-Rhône 14M 4/5 14-cylinder air-cooled radial engines, 522
kW (700 hp) each

Performance
Maximum speed: 425 km/h (229 knots, 264 mph) at 5,500 m (18,045 ft)
Cruise speed: 299 km/h (162 knots, 186 m/h) at 4,500 m (14,765 ft) (recon
cruise)
Range: 1,500 km (810 nmi, 932 mi)
Service ceiling: 8,500 m (27,890 ft)
Rate of climb: 8.4 m/s (1,653 ft/min)

Armament

Guns: (original armament) 1x fixed, forward-firing 7.5 mm MAC 1934 machine gun
1x fixed, rearward-firing 7.5 mm MAC 1934 machine gun
1x flexibly mounted, rearward-firing 7.5 mm MAC 1934 machine gun

(Final armament) 3× fixed forward firing machine guns under fuselage
4× fixed, forward firing machine guns under outer wings
3× semi fixed, rearward firing machine guns in ventral mount
2× flexibly mounted machine guns in aft cockpit

Bombs: 4x 50 kg (110 lb) bombs




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