The Arsenal VG.33

by Chris Chant on 18/02/2016

The Arsenal de l’Aéronautique was created in 1936 as the French government nationalised and then rationalised the widely scattered and completely inefficient French aero industry. The new organisation created several advanced warplanes, primarily based on the designation suffix VG as an abbreviation indicating Ingenieur-Général Michel Vernisse and Jean Gaultier, who were the establishment’s head and chief designer respectively. One of the earlier of these types was the VG.30, which was a lightweight fighter designed to compete with the Caudron C.713 Cyclone. Planned with a powerplant of one Potez 12Dc V-12 engine, an air-cooled unit rated at 610 hp (455 kW), the VG.30 was a clean low-wing monoplane of cantilever all-wooden construction with tailwheel landing gear whose wide-track main units retracted into the undersurfaces of wings that had an area of 150.695 sq ft (14.00 m²).

The type recorded its maiden flight in October 1938 with the powerplant of one Hispano-Suiza 12Xcrs V-12 engine, a liquid-cooled unit rated at 690 hp (515 kW), as the Potez 12Dc was not available. The proposed armament was one 20-mm cannon and two 0.295-in (7.5-mm) machine guns, but it seems that this was never installed in this prototype fighter.

The next variant of this basic theme remained only a project, and was the VG.31 with the Hispano-Suiza 12Y-31 inverted V-12 engine rated at 860 hp (642 kW) and wings that possessed an area of 129.17 sq ft (12.00 m²). Research suggested that the performance gains of this model over the VG.30 would be minimal, that handling would be poorer, and that both the stalling and landing speeds would be significantly higher. Next in numerical sequence, but in fact completed after the VG.33, was the VG.32. This was the VG.30 revised with a US engine; the Allison V-1710-C15 inverted V-12 engine rated at 1,040 hp (776 kW). The VG.32 had not been flown when it was captured at Villacoublay as the Germans conquered France in the six-week campaign of May and June 1940.

Production standard

The VG.33 was thus the first of the VG series to reach what was in effect the production stage, and was a combination of the VG.30 airframe with the powerplant proposed for the VG.31. The VG.33 was based on an oval-section fuselage, and a clean nose entry was ensured by locating the radiator for the engine coolant in a low-drag bath under the fuselage in line with the enclosed cockpit. The VG.33.01 initial prototype recorded its maiden flight in the late spring of 1939 and was delivered for service trials in August of the same year, just one month before the Germans started their invasion of Poland and thereby triggered World War II. The VG.30.02 second prototype was built with a powerplant of one Hispano-Suiza 12Y-45 engine rated at 910 hp (679 kW), but was not assembled in its planned form: the wings were married to the fuselage of the VG.31 to create the VG.33.03 prototype, and the fuselage was used in the creation of the VG.34. After the completion of its trials, the VG.33.03 was sent as the pre-production prototype to the Chantiers Aéro-Maritimes de la Seine, which had received an order for 200 VG.33 aircraft in the C.1 (Chasse mono-place, or single-seat fighter) category shortly after the Munich crisis of the autumn of 1938.

By the time of the German occupation of the Paris region in June 1940, the company had 160 aircraft under construction and had completed 44 aircraft including three additional prototypes. Only about 12 of these aircraft could be flown from Sartrouville before the Germans overran the area, and these were placed in storage at Châteauroux in the unoccupied part of France for possible later use by the Vichy French air force. The aircraft were discovered as the Germans took over the unoccupied zone of France after the Anglo-American landings in French North-West Africa in November 1942.

Continued development

First flown in the spring of 1940, the VG.34 was the prototype for a development with the Hispano-Suiza 12Y-45 engine rated at 910 hp (679 kW). The prototype recorded a maximum speed of 311 kt (358 mph; 575 km/h) at 21,325 ft (6500 m).

Next in numerical sequence came the VG.35, which was a single prototype conversion from VG.33 standard with the powerplant of one Hispano-Suiza 12Y-51 engine rated at 1,100 hp (820 kW), but before completion this machine was revised to VG.36 standard with a shallower radiator bath: the machine had made only a few flights before the fall of France. The VG.37 was a project with a Hispano-Suiza engine rated at 1,000 hp (746 kW), but this did not reach fruition and the same fate befell the VG.38 with a Hispano-Suiza 77 inverted V-12 engine fitted with two Brown-Boveri turbochargers. The VG.38 was to have been a development with the Hispano-Suiza 12Y-77 engine, but was not built.

The last development was the VG.39, which was powered by a Hispano-Suiza 89ter inverted V-12 engine rated at 1,280 hp (954 kW) and had a revised wing carrying six 0.295-in (7.5-mm) MAC 1934 M39 machine guns to supplement the 20-mm HS-404 engine-mounted cannon. This prototype recorded a maximum speed of 337 kt (388 mph; 625 km/h) at 18,865 ft (5750 m). It was proposed that it would enter production as the VG.39bis, with the shallower radiator bath and rear fuselage of the VG.36, and that the Hispano-Suiza 89ter engine should later be replaced by a Hispano-Suiza 12Z-17 inverted V-12 engine rated at 1,600 hp (1193 kW), but neither type were built. Two more designs were projected on the basis of the VG.39bis’s airframe: the VG.40 would have been powered by the Rolls-Royce Merlin III liquid-cooled V-12 engine, and the VG.50 by the Allison V-1710-39 liquid-cooled V-12 engine. Neither were built.

France had placed great faith in the VG.30 series, for in addition to actual production of the VG.33 planned to mass-produce the VG.32 (with the fuselage of the VG.36 and the wing of the VG.39 but no 20-mm cannon as this could not be installed in the Allison engine) and the VG.39. Extra production facilities were ordered at the factories of Couzinet and the Société Nationale de Constructions Aéronautique du Nord, but neither of these facilities were ready to begin production at the time of France’s defeat in June 1940.

On the subject of the fall of France, history blogger and Author, Rupert Colley, writes:

“Hitler’s forces entered a largely deserted Paris on 14 June, over two million Parisians having fled south. Soon the swastika flag was flying from the Arc de Triomphe”

Specification

Arsenal VG.33

Type: fighter

Accommodation: pilot in the enclosed cockpit

Armament: one 20-mm Hispano-Suiza HS-404 fixed forward-firing cannon with 60 rounds in a moteur-canon installation to fire through the hollow propeller shaft, and four 0.295-in (7.5-mm) MAC 1934 M39 fixed forward-firing machine guns in the leading edges of the wing

Equipment: standard communication and navigation equipment, plus a Baille-Lemaire 40 reflector gun sight

Powerplant: one Hispano-Suiza 12Y-31 liquid-cooled inverted V-12 piston engine rated at 860 hp (642 kW) for take-off

Fuel: internal fuel 88 Imp gal (105.7 US gal; 400 litres) plus provision for 44 Imp gal (52.8 US gal; 200 litres) of auxiliary fuel in two 22 Imp gal (26.4 US gal; 100 litre) fixed underwing tanks; external fuel none

Wing: span 35 ft 5.25 in (10.80 m); area 150.695 sq ft (14.00 m²)

Fuselage: length 28 ft 0.67 in (8.55 m); height 10 ft 10.25 in (3.31 m) with the tail up

Weights: empty 4,519 lb (2050 kg); normal take-off 5,853 lb (2655 kg); maximum take-off 6,393 lb (2900 kg)

Performance: maximum level speed 319 kt (367 mph; 590 km/h) at sea level declining to 301 kt (347 mph; 558 km/h) at 17,060 ft (5200 m); cruising speed not available; initial climb rate not available; service ceiling 36,090 ft (11000 m); maximum range 955 nm (1,100 miles; 1770 km) with auxiliary fuel; typical range 648 nm (746 miles; 1200 km) with standard fuel

[Photos by Aerofred and Bob Wallace]

{ 1 comment… read it below or add one }

Bruce Saint February 8, 2017 at 12:00 pm

This fantastic special design of the Model Arsenal VG-33

Reply

Leave a Comment

Previous post:

Next post: