SNCASE SE-400

The SNCASE SE-400 was a prototype French twin-engined coastal patrol floatplane of the Second World War. A single example was flown, but development was abandoned in May 1940 owing to the German invasion of France.

SE-400
Role	Coastal reconnaissance floatplane
National origin	France
Manufacturer	SNCASE
First flight	31 December 1939
Status	Prototype
Number built	1

Design and development

In 1937 the French Air Ministry issued specification A46 for a three-seat coastal reconnaissance seaplane to replace the obsolete CAMS 37 biplane flying boats of the French Navy. To meet this requirement, the Société Nationale des Constructions Aéronautiques du Sud-Est (SNCASE) designed a twin-engined monoplane floatplane, the SE-400, work beginning on construction of two prototypes in March 1938.^[1][2]

The SE.400 was of mixed construction, with a steel tube fuselage and wooden wings. It had a twin tail and was powered by two 655 hp (489 kW) Gnome-Rhône 14M radial engines. The aircraft's undercarriage consisted of two light alloy floats mounted beneath the engines.^[1]

Operational history

The first prototype, the SE.400-01 made its maiden flight from Marignane on 31 December 1939.^[1] Flight testing showed that the SE-400 suffered from stability problems, and the aircraft had a new, larger, tail assembly fitted and its nose lengthened. These modifications resolved the aircraft's handling problems,^[3] but by this time the competing Breguet Nautilus had been ordered into production.^[4]

The war situation and the continuing delays in the program resulted in the development of the SE-400 being abandoned on 24 May 1940, with the second prototype, a landplane powered by two 500 hp (370 kW) Lorraine 9N Algol engines,^[a] left incomplete.^[6] The first prototype was found by Italian troops at Vitrolles, but while the aircraft's engines and propellers were removed, the rest of the aircraft remained intact until 1945.^[5]

Operators

 France

• French Navy

Specifications

Data from War Planes of the Second World War^[7]

General characteristics

• Crew: 3
• Length: 13.50 m (44 ft 3 in)
• Wingspan: 19.35 m (63 ft 6 in)
• Height: 4.50 m (14 ft 9 in)
• Wing area: 52.00 m² (559.7 sq ft)
• Gross weight: 5,500 kg (12,125 lb)
• Powerplant: 2 × Gnome-Rhône 14M 8/9 14-cylinder air-cooled radial engines, 488 kW (655 hp) each

Performance

• Maximum speed: 290 km/h (180 mph, 160 kn) at 2,000 m (6,560 ft)
• Cruise speed: 159 km/h (99 mph, 86 kn) (econ cruise)
• Range: 958 km (595 mi, 517 nmi) at 159 km/h (99 mph)
• Endurance: 6 hr
• Service ceiling: 4,000 m (13,120 ft)

Armament

• Guns: 1× 7.5 mm Darne machine gun at dorsal position
• Bombs: 2× 75 kg (165 lb) bombs and 2× flares

See also

Aircraft of comparable role, configuration, and era

• Breguet Nautilus

Related lists

• List of flying boats and floatplanes