four-seat cabin touring monoplane of the 1930s with an excellent
standard of reliability and comfort, the Caudron C.630 Simoun
(Sandstorm) incorporated many technical features developed in designer
Marcel Riffard's series of Coupe Deutsche de la Meurthe racers.
The experimental C.500
Simoun IV and C.620 Simoun VI were exhibited at the Paris Salon de
l'Aeronautique in 1934. The C.620 was intended for the Challenge
Internationale de Tourisme competition and its comfortable individual
seats, deep windscreen and three large windows on each side of the
cabin found greater favour than the more conventional layout and
shallow windscreen and windows of the C.500 Simoun IV. There was
clearly a market for the Simoun with its new Renault six-cylinder
engine and, apart from the one-off C.520 and two long-range versions of
the C.620 with extra fuel tanks in the cabin, the production C.630 was
the next version to appear.
The C.630 was an
elegant low-wing cantilever monoplane of wooden construction, the wing
covered by plywood plus fabric and incorporating flaps that occupied
the entire trailing edge inboard of the ailerons. The slab-sided
fuselage had light alloy covering for the carefully streamlined curved
underside and roof. The non-retractable tailwheel landing gear had
cantilever main legs with oleo-pneumatic shock absorbers, the legs,
main wheels and castoring tailwheel all enclosed in streamlined
fairings. Differential brakes were standard.
The prototype C.620
with a 170 hp (127 kW) Renault Bengali 6Pfi engine was flown for the
first time in October 1934. Only a few months later, in mid-1935,
deliveries began of the C.630 series with a 180 hp (134 kW) Renault
6Pri (or 6Q-07) driving a Ratier variable-pitch metal propeller. The
new type found immediate favour, with orders for some 70 private
tourers following. Commercially, 12 C.630s established France's first
regular air mail service, each in an elegant light blue finish with a
silver arrow along the fuselage side; these belonged to Air Bleu, the
air-mail subsidiary of Air France. Air Bleu's first flight from its Le
Bourget base was on 10 July 1935. After somewhat erratic early
progress, the criss-cross of domestic postal routes resumed in June
1937 and continued until May 1939, establishing a 95 per cent
regularity record and carrying over 45 million letters. Other Simouns
flew air mail routes in Madagascar.
A number of variants
followed the C.630, but only the C.635 with a 220 hp (164 kW) 6Q-09 or
6Q-15 Bengali engine was built in quantity. Five of the type in red
livery equipped the French VIP Escadrille Ministerielle, while during
1935-6 the French services placed initial orders for the militarised
C.635M version, 110 for the Armée de l'Air and 29 for the Aéronavale.
Other military and naval orders followed, the Simoun being used widely
for liaison, as a General Staff transport, and as a transition or
navigation trainer. At the outbreak of World War II some 60 civil
Simouns were requisitioned by the Armée de l'Air for the hastily formed
Sections d'Avions Estafettes (air couriers) and Sections d' Avions
Sanitaires (air ambulances). During the invasion of France two aircraft
were known lost, the remaining captured aircraft were used by Vichy
forces. Of 103 Simouns captured by the Germans in November 1942, when
they took over the Unoccupied Zone of France from the Vichy regime, 65
were used for training and liaison. Large numbers of Simouns flew with
the French in North Africa, although the attrition rate was high.
Several examples were reported in the UK during the war.
Many well-known French
pilots of the 1930s used the Simoun in long distance attempts. Among
those to gain success were Genin and Robert, who flew a C.635
(registered F-ANMA and named Gody Radio) from Le Bourget on 18
December 1935, 57 hours 36 minutes later landing at Antananarivo in
Madagascar, having covered a distance of 5,384 miles (8665 km). Marie
Bastie flying solo took her C.635 Jean Mermoz from Orly on 12
December 1936, and reached Dakar in West Africa on 19 December and then
crossed the South Atlantic to Natal in Brazil, a distance of 1,926
miles (3100 km) averaging 164 mph (264 km/h). This beat the record held
previously by Jean Batten of New Zealand. In another solo flight from
France, in August 1937, Maryse Hilsz reached Saigon in less than four
Other more famous
fliers were less fortunate. On a second attempt to reach Tokyo from
Paris, Marcel Doret and his partner Micheletti made an emergency
landing in Japan and were badly hurt. The great airman-poet Antoine de
Saint Exupery, attempting to reach Tierra del Fuego from New York in
1937, crashed on take-off at Guatemala City and was seriously injured.
A number of Simouns remained in flying condition post-war. One was used
(on the ground, alas) in the film entitled The Little Prince,
appropriately enough a story written by Antoine de Saint Exupery. In
August 1944, the French Provisional Government began to nationalize the
aircraft industry. Caudron, due to its activities during the German
occupation, was one of the first companies to be broken up under the
new policy. However, some Caudron designs such as the C.449 Goéland and
C.800 glider continued to be produced post-war.
Caudron C.500 Simoun IV
- The experimental C.500 Simoun IV was exhibited at the Paris Salon de
l'Aeronautique in 1934.
Caudron C.520 Simoun -
Another single aircraft similar to the C.500 but intended as a
pre-production aircraft for the C.630 series.
Caudron C.620 Simoun VI
- This experimental C.500 Simoun IV was also exhibited at the Paris
Salon de l'Aeronautique in 1934. The C.620 was intended for the
Challenge Internationale de Tourisme competition and its comfortable
individual seats, deep windscreen and three large windows on each side
of the cabin found greater favour than the more conventional layout and
shallow windscreen and windows of the C.500 Simoun IV. Powered by 170
hp (127 kW) Renault Bengali 6Pfi engine it was flown for the first time
in October 1934.
Caudron C.620 Simoun
Long Range - Two aircraft were produced and fitted with extra fuel
tanks in the cabin in order to extend the range.
Caudron C.630 Simoun -
Deliveries began of the C.630 Simoun series in mid-1935 powered by a
180 hp (134 kW) Renault 6Pri (or 6Q-07) engine driving a Ratier
variable-pitch metal propeller. The new type was an immediate success,
with private orders for some 70 aircraft soon following. Only 20
aircraft were eventually built.
Caudron C.631 Simoun -
Three aircraft powered by a 220 hp (164 kW) Renault Bengali 6Q-01
Caudron C.632 Simoun -
A single aircraft powered by a 220 hp (164 kW) Renault Bengali 6Q-01
6-cylinder engine with only minor detail changes.
Caudron C.633 Simoun -
Six aircraft produced with a modified fuselage and powered by a 180 hp
(134 kW) Renault Bengali 6Q-07 6-cylinder inline engine.
Caudron C.634 Simoun -
Three aircraft produced with a modified wing, increased take-off weight
and a 220 hp (164 kW) Renault Bengali 6Q-01 or 6Q-09 6-cylinder inline
Caudron C.635 Simoun -
Main production type incorporating an improved cabin layout and powered
by a 220 hp (164 kW) Renault Bengali 6Q-01 or 6Q-09 6-cylinder inline
piston engine. 46 aircraft were built, but some earlier aircraft were
converted to this standard.
Caudron C.635M Simoun -
This was a version of the C.635 built to military specifications
(detailed modifications based on the service) and with standard
military equipment installed. Powered by a 220 hp (164 kW) Renault
Bengali 6Q-09 or 6Q-15 6-cylinder inline piston engine. 436 aircraft
were built for the Armée de l'Air and another 52 aircraft were built
for the Aéronavale. A single aircraft was also produced for the US
Naval attaché in Paris.
C.635M Simoun "Sandstorm")
Type: Four Seat
Trainer, Liaison, Air Ambulance, Staff Transport & Civil Touring/Mail
Pilot & Co-Pilot/passenger and two more seats for passengers plus up to
330.75 lbs (150 kg) of baggage and/or cargo.
Marcel Riffard of the Société Anonyme des Avions Caudron
Société Anonyme des Avions Caudron in Issy-les-Moulineaux and
Billancourt (Renault engines). In 1933 the Caudron and Renault
companies were amalgamated. In 1936 the french aircraft industry was
nationalised, but the Société Anonyme des Avions Caudron managed to
survive as an independent company. During the German occupation, the
Caudron and Renault companies were closely linked with a portion of the
Renault factory in Billancourt being devoted to Caudron aircraft
220 hp (164 kW) Renault Bengali 6Q-09 6-cylinder inline piston engine.
Maximum speed 186 mph (300 km/h) at sea level; economical cruising
speed 162 mph (260 km/h); service ceiling 19,685 ft (6000 m).
Range: 932 miles
(1500 km) on internal fuel.
equipped 1,664 lbs (755 kg) with a maximum take-off weight of 3,042 lbs
34 ft 1 1/2 in (10.40 m); length 29 ft 10 1/4 in (9.10 m); height 7 ft
6 1/2 in (2.30 m); wing area 172.23 sq ft (16.0 sq m).
Simoun IV (experimental), C.520, C.620 Simoun VI (experimental), C.620
Simoun Long Range, C.630 Simoun, C.631, C.632, C.633, C.634, C.635,
flight (C.500/C.620) early 1934; first flight (C.620) October 1934;
first commerical flight (C.630) on 10 July 1935.
France (Air Bleu, Armée de l'Air & Aéronavale). Air Bleu was the
airmail subsidiary of Air France.