"The best fighter in the world." In 1937, these words were used at the Brussels Air Show to define the prototype of Morane-Saulnier's latest combat plane, which had recently completed a series of flight tests and official evaluations. Aside from this advertising statement, it became the founder of a long series of over 1,000 aircraft (1,081 to be precise) that were produced up till June 1940 and that earned a prominent place in aviation history for many reasons. The Morane-Saulnier M.S.406 was the first modern aircraft of its category to go into service in the units of the Armee de I'Air and it was built in remarkable quantities compared to French production standards of the time, second only to the two-engine Potez 630 series, and, above all, it was the fighter available in the greatest numbers when the war broke out.

The project was launched on the basis of specifications issued in 1934, and the prototype (built in great secrecy) made its first flight on August 8, 1935. Designated the M.S.405, it was a low-wing monoplane with retractable landing gear, powered by an 860 hp Hispano-Suiza 12 Ygrs engine. It had an all-metal airframe with a covering of aluminium, plywood, and canvas, and an enclosed cockpit. The armament consisted of a 20 mm cannon installed in the propeller shaft and two machine guns in the wings.

Right from its first flight, the features of the aircraft proved to be excellent, especially its speed, which reached 303 mph (489 km/h) at 13,200 ft (4000 m) and just over 250 mph (400 km/h) at sea level. The latter meant that the Morane-Saulnier became the first French fighter to break the 250 mph (400 km/h) barrier. After the initial flight tests, the first prototype was joined by a second (with modifications to the propeller and the wings), and both these aircraft faced a series of official evaluations. At the beginning of 1937, the company received an order for 15 pre-series aircraft, and the second of these (which took to the air on May 20, 1938) became the progenitor of the M.S.406, the differences consisted mainly in the use of a different engine, a different type of propeller, and in structural modifications, especially to the wing. The aircraft was chosen for production in this definitive version on the basis of an order that, in March 1938, amounted to 1,000 planes. In order to guarantee this large quantity, assembly lines were set up in several factories and, within a short space of time, the delivery rate was quite high. By September 1939, 572 M.S.406s had already left the factories.

1st Escadrille Groupe de Chasse I/2 Armee de l'Air, France 1940

The first unit to receive the new fighter was the 6th Escadre de Chasse, in December 1938. Other units followed, and immediately before mobilization in August 1939, 12 groups had been equipped with the aircraft. However, from the beginning of its operational service, it became apparent that the 406 was distinctly inferior to its direct adversary, the Messerschmitt Bf.109E. During the Battle of France, 150 Moranes were lost, as compared to 1 91 enemy aircraft definitely hit and another 89 probably hit. A further hundred or so Moranes were destroyed on the ground, and about 150 were damaged beyond repair by the French crews to prevent their failing into enemy hands.

After the armistice, some Morane 406s remained in service in the Vichy air force (where they were mainly used for training), and others were handed over by the Germans to Finland, which had received 30 aircraft in 1940. The 'Morko Moraani' was created in Finland by converting French Morane-Saulnier MS.406 and MS.410 fighters to accept captured Soviet Klimov M-105P engines. The M-105P was a development of the original Hispano-Suiza HS 12Y engine, and developed 200 hp (149 kw) more. A total of 41 were converted; the engines were supplied by Germany. Germany also supplied the new Mauser 20 mm cannon and oil cooler. The Morko remained in service until 1948.

Another foreign buyer was Switzerland, which, after having acquired two M.S.406s, built 82 aircraft on license (designated EFW-3800) as well as 207 of a subsequent home-developed version known as EFW-3801.

Specifications (Morane Saulnier MS.406)

Type: Single Seat Fighter

Design: Morane Saulnier

Manufacturer: Morane Saulnier, SNCASO, Dornier-Werke Switzerland

Powerplant: One 860 hp (642 kw) Hispano-Suiza 12Y 31 12-cylinder inverted Vee, liquid cooled, piston engine.

Performance: Maximum speed 302 mph (486 km/h) at 16,400 ft (5000 m); service ceiling 30,840 ft (9400 m).

Range: 497 miles (800 km) with internal fuel stores.

Weight: Empty 4,178 lbs (1895 kg) with a maximum take-off weight of 5,600 lbs (2540 kg).

Dimensions: Span 34 ft 10 in (10.65 m); length 2 ft 9 in (8.15 m); height 9 ft 3 in (2.82 m); wing area 172.16 sq ft (16.0 sq m).

Armament: One 20 mm Hispano Suiza HS-404 (or HS-59) gun (60 rounds) and two 7.5 mm (0.295 in) MAC-1934 guns (300 rounds each).

Variants: MS.406 (prototype and production).