When the nationalisation of the French aircraft industry resulted in the creation of the Société Nationale de Constructions Aéronautiques du Centre (SNCAC) from the merger of Farman Aviation Works and Hanriot in 1936, the new company inherited Farman’s experience in high-altitude research, and this research continued.

SNCAC continued work on high-altitude aircraft, proposing two pressurised bombers in 1938. The first, the NC.140, was a four-engined bomber using the wings of the Farman F.223.3 but was quickly abandoned in favour of the smaller, twin-engined NC.150. The NC.150 was a mid-winged monoplane with a retractable tailwheel undercarriage which was designed to make maximum use of non-strategic materials such as wood. The wings were of mixed construction, with a metal centre-section, and wood outer wings that had metal spars, wooden ribs and plywood skinning. Similarly, the fuselage had wooden forward and aft fuselage section connecting to the metal centre section, while the twin tail was of wooden construction with plywood skinning. It was to be powered by two Hispano-Suiza 12Y V12 engines, with power being maintained at high altitudes by using a single three-stage supercharger driven by a separate Hispano-Suiza 12X engine mounted in the fuselage.

SNCAC began work on two prototypes as a private venture in 1938. These two prototypes were not to be fitted with cabin pressurisation, although this was planned for a third prototype. The French Air Ministry placed an order for the two prototypes on 24 April 1939, with the second aircraft to carry full armament.

The first prototype, designated NC.150.01, made its maiden flight from Toussus-le-Noble on 11 May 1939. Following the tests, the aircraft received numerous improvements: modifications of compressors, addition of a glass nose, and modified rudders.

Meanwhile, the French Air Ministry had become worried about possible delays to the Lioré et Olivier LeO 45 and Amiot 354 twin-engined bombers which were planned to re-equip the medium bomber squadrons of the Armée de l’Air caused by shortages of light alloys, and after successful testing in early 1940, ordered a change of plans. Pressurisation was to be abandoned, and the unusual central supercharger with its dedicated engine (known as the “bi-tri” concept) was to be replaced by individually supercharged engines.

The NC150 was transferred to the CEMA (Test Center of the Air Materials) at the beginning of 1940, while the construction of the second prototype, equipped this time, of its armament. The events called into question the project and it was asked the SNCAC to abandon the pressurized bi-tri formula in favour of more conventional formulas using Hispano-Suiza 12Y compressor or Pratt & Whitney Double Wasp engines respectively NC152 and NC153.

Two production versions were planned, the NC.152, powered by Hispano-Suiza engines, and the NC.153, with imported American radial engines. Although testing was promising, and orders were planned for a modified version as a back-up for the Lioré et Olivier LeO 45 and Amiot 354 bombers, the surrender of France in June 1940 ended development with only the single example being built, both the second and third prototypes being abandoned before completion. The first prototype, NC150-01, disappeared after its evacuation on Bordeaux-Mérignac, the second one was never finished, and the third, NC151-01, which was to be the final prototype equipped with pressurization, never came into being.

NC.150
Powerplant: 2 × Hispano-Suiza 12Y 32/33, 720 kW (960 hp) each
Powerplant: 1 × Hispano-Suiza 12Xirs liquid-cooled V12 engine driving NC-C2 supercharger, 510 kW (690 hp)
Wingspan: 21.882 m (71 ft 9.5 in)
Wing area: 61.10 sq.m (657.7 sq ft)
Length: 17.60 m (57 ft 9 in)
Height: 4.19 m (13 ft 9 in)
Empty weight: 7,733 kg (17,048 lb)
Gross weight: 10,077 kg (22,216 lb)
Maximum speed: 600 km/h; 324 kn (373 mph) at 8,000 m (26,250 ft)
Cruise speed: 510 km/h; 275 kn (317 mph) at 8,000 m (26,250 ft) (long-range cruise)
Range: 2,200 km; 1,188 nmi (1,367 mi)
Service ceiling: 11,380 m (37,350 ft)
Time to altitude: 19 min 7 s to 8,000 m (26,250 ft)
Crew: Four