Couzinet 70

70 Arc-en-Ciel
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The Arc-en-Ciel at Fernando de Noronha, Brazil on 14 June 1934
Role	Long-range commercial monoplane
Manufacturer	Société des Avions René Couzinet
First flight	11 February 1932
Introduction	1934
Primary user	Aéropostale
Produced	3

The Couzinet 70 was a 1930s French three-engined commercial monoplane built by Société des Avions René Couzinet founded by René Couzinet.

Design and developments

The Couzinet 70 Arc-en-Ciel III (en Rainbow) was developed from the 1920s Couzinet 10 Arc-en-Ciel and Couzinet 30. The Couzinet 70 was developed originally as a mail plane for use of Aéropostale's South Atlantic service. The aircraft was a low-wing monoplane with a fixed tailwheel landing gear. The aircraft was powered by three Hispano-Suiza 12Nb inline piston engines. The two wing mounted engines could be accessed in flight through tunnels in the wing. After route-proving in 1933 the aircraft was modified and re-designated the Couzinet 71 and entered service with Aéropostale in May 1934.

Developments

There were two further developments based on the Couzinet 70. Only one of each type was built.

Couzinet 101

A 3-seat touring aircraft with similar layout to the Arc en Ciel was produced as the Couzinet 101, powered by three 85 hp (63 kW) Pobjoy R radial engines. During the Spanish Civil War the Couzinet 101 became a transport in the Spanish Republican Air Force.

Couzinet 103

The latest development in the series was the Couzinet 103 with three 135 hp (101 kW) Salmson 9Adr radial engines which could carry two crew (or one pilot and passenger) and four passengers in a separate cabin.

Variants

10 Arc en Ciel

The original prototype four place bomber, later converted to the 'Couzinet 27

27 Arc en Ciel II

Converted from the Couzinet 10 but crashing on 8 August 1928

70 Arc en Ciel III

Three-engined Hispano-Suiza 12Nb powered prototype, one built and converted to a Couzinet 71

71

Prototype modified for service as a mailplane.

Operators

France

• Aéropostale

Spain

• Spanish Republican Air Force - Couzinet 101

Specifications (70/71)

General characteristics

• Crew: Four
• Length: 16.15 m (52 ft 11¾ in)
• Wingspan: 30 m (98 ft 5 in)
• Height: 4 m (13 ft 1½ in)
• Wing area: 90 m² (968.78 ft²)
• Empty weight: 7310 kg (16,116 lb)
• Gross weight: 16,790 kg (37,015 lb)
• Powerplant: 3 × Hispano-Suiza 12Nb V-12 liquid-cooled piston engine, 485 kW (650 hp) each

Performance

• Maximum speed: 280 km/h (174 mph)
• Range: 6800 km (4225 miles)