Nord 3400

The Nord 3400 Norbarbe is a French single-engine, two-seat observation and casualty-evacuation aircraft built by Nord Aviation for the French Army Light Aviation (ALAT). It is a braced high-wing monoplane with tandem seating and fixed tailwheel landing gear. Deliveries to the ALAT began in July 1959. The type is known for its short-field performance, with take-off and landing runs of under 100 m.

Development

In 1956 the French government launched a programme for a light observation and casualty-evacuation aircraft to replace the Piper L-18 and Cessna L-19 in Army service. The design submitted by the Société nationale des constructions aéronautiques du Nord (SNCAN) was the only one selected by the evaluation commission, which announced its decision on 11 January 1957. The prototype, F-MBTD, first flew on 20 January 1958. It was powered by a 179 kW (240 hp) Potez 4D-30 engine. A second prototype followed with increased wing span and area and a 194 kW (260 hp) Potez 4D-34 engine. The French Army ordered 150 aircraft to the second prototype's configuration.

Design

The Nord 3400 has a rectangular, unswept, strut-braced high wing with 2° of continuous dihedral and a NACA 23015 aerofoil. Each wing half can be pivoted rearward for folding. The fuselage is a metal-tube structure with partial fabric covering. The wing is metal-skinned forward of the spar and at the root, where two 110-litre self-sealing flexible fuel tanks are housed. The remaining wing surface is fabric-covered.

High-lift devices run the full span. The centre section carries camber flaps with a leading-edge deflector, and lower-surface flaps are fitted to the ailerons. The tail is conventional, with a single fin of metal construction and fabric-covered control surfaces.

The pilot and observer sit in tandem in an enclosed cabin, and the observer's seat can rotate through 360 degrees. Some sources give a seating capacity of two or three. The production standard is the 194 kW (260 hp) Potez 4D-34, a four-cylinder, air-cooled, inverted in-line engine, although some sources state that early aircraft flew with the 179 kW (240 hp) Potez 4D-30 before being re-engined. The original two-blade Ratier propeller was replaced from 1965 by a three-blade Hartzell variable-pitch unit.

Dimensions include a span of 13.11 m, a length of 8.42 m and a wing area of 20.82 m², giving an aspect ratio of 8.2. Equipped empty weight is 920 kg and maximum take-off weight is 1,350 kg. Performance figures are as follows:

• Maximum speed: 235 km/h
• Cruise speed: 200 km/h
• Stall speed: 70 km/h
• Rate of climb: 7 m/s
• Ceiling: 3,000 m
• Range: 1,000 km

Operational History

The ALAT received its 150 aircraft between 9 July 1959 and March 1961. It later transferred six aircraft to the National Gendarmerie, which operated them as observation aircraft from 1972 to 1974.

Variants

• Nord 3400-01: First prototype, powered by a 179 kW (240 hp) Potez 4D-30 engine, with wings of 12.7 m span and 19.5 m² area.
• Nord 3400: Second prototype and production standard, with a 194 kW (260 hp) Potez 4D-34 engine and wings of increased span and area.