Morane-Saulnier M.S.406

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Morane-Saulnier M.S.406

Morane-Saulnier M.S.406 at Rayack
Type	fighter
Manufacturer	Morane-Saulnier
Designed by	Robert Morane and Raymond Saulnier
Maiden flight	8 August 1935 (M.S.405)
Introduced	1938
Number built	1,176

The M.S.406 was a French Armée de l'Air fighter aircraft built by Morane-Saulnier starting in 1938. Numerically it was France's most important fighter during the opening stages of World War II.

The type was generally free of problems but was under-powered, weakly armed and lacked full armour protection when compared to its contemporaries. Most critically, it was out-performed by the Messerschmitt Bf 109E during the Battle of France. Although it was one of the few modern fighters available to the Armée de l'Air in quantity at the time, its shortcomings resulted in high casualties amongst French pilots, despite valiant effort. The design held its own in the early stages of the war (the so-called Phony War), but when the war restarted in earnest in 1940, 400 were lost in combat and on the ground for only 175 kills in return.

1 Design and development
2 Swiss variants
- 2.1 D-3800
- 2.2 D-3801
3 Finnish variants
- 3.1 Mörkö-Morane
4 Operational history
5 Operators
6 Specifications (M.S.406)
7 References
8 Related content

[edit] Design and development

[edit] M.S.405

In 1934, the Service Technique Aéronautique (Aeronautical Technical Service) of the Armée de l'Air issued a requirement for a new and completely modern single-seat fighter (what they referred to as a C1 design), with a monoplane layout and retracting gear.

Morane-Saulnier's response was the M.S.405, a low-wing monoplane of mixed construction, with fabric covered wood tail, but a bonded metal/wood material (Plymax) fixed to duralumin tubing. Plymax consisted of a thin sheet of duralumin bonded to a thicker sheet of plywood. Morane-Saulnier had a long history of producing warplanes dating back to pre-World War I years but in the inter-war period, they had concentrated on civil designs. The plane was a departure for them, their first low-wing monoplane, first enclosed cockpit and their first with retracting gear. Prior to this, their most modern designs were fixed-gear parasol monoplanes.

The new 860 hp (640 kW) Hispano-Suiza HS 12Y-grs engine driving a two-pitch Chauvière propeller powered the first prototype, which flew on 8 August 1935. Development was very slow, and the second prototype with a 900 hp (670 kW) HS 12Y-crs engine didn't fly until 20 January 1937, almost a year and a half later. With the new engine the plane reached 275 mph (443 km/h), which was fast enough to secure an order for a further 16 pre-production prototypes, each including improvements on the last version.

[edit] M.S.406

The result of these changes was the M.S.406. The two main changes were the inclusion of a new wing structure that saved weight, and a retractable radiator under the fuselage. Powered by the production 860 hp (640 kW) HS 12Y-31 engine, the new design was over 5 mph (8 km/h) faster than the 405, at 304 mph (489 km/h). Armament consisted of a 20 mm Hispano-Suiza HS-9 or 404 cannon with 60 rounds, which fired through the piston banks in the engine, and two 7.5 mm MAC 1934 machine guns in the wings with 300 rounds each.

[edit] M.S.410

While the 406s were entering service in 1939, an upgrade series was started to improve the design. The result was the M.S.410, which included a stronger wing, simpler fixed radiator in place of the earlier retractable design, four belt-fed MAC guns in place of the earlier two drum-fed weapons, and exhaust ejectors for additional thrust. The added thrust boosted the top speed to 316 mph (509 km/h), an improvement of about 10 mph (16 km/h) over the 406.

Production had just started when France fell, and only five examples had been completed. Production was allowed to continue under German supervision, converting earlier 406s to the 410 standard, but many of these received only the new wings.

[edit] M.S.411, M.S.412

A single example of the M.S.411 was constructed by converting the 12th aircraft of the pre-production line with the 406 wing and the 1,000 hp (750 kW) HS 12Y-45 engine. A later modification was started as the M.S.412 with the 1,050 hp (780 kW) HS 12Y-51 engine, but this was not completed by the time the war ended.

[edit] M.S.450

In 1939, Hispano started prototype deliveries of the new Hispano-Suiza 12Z engine of 1,300 hp (970 kW). One was fitted to a modified 410 to create the M.S.450 that had dramatically better performance, especially at altitude. However the engine never entered production before France fell, and the similarly modified Dewoitine D.520 (the D.523/D.551) was considered a better design for the engine anyway.

[edit] Other variants

The M.S.406 airframe was also used in a number of other projects. The M.S.430 was a two-seat trainer built by inserting a "plug" in the middle for the trainer pilot and using the much less powerful 390 hp (290 kW) Salmson radial engine. The M.S.435 was a more powerful version with the 550 hp (410 kW) Gnome-Rhône 9K engine.

[edit] Swiss variants

D-3801, a Swiss license-built copy of MS-406

Morane D-3801 J-143 (Association Morane Charlie-Fox)

[edit] D-3800

In 1938, Switzerland licensed the M.S.406 for local production as the D-3800. Two of the pre-production M.S.405 samples were completed as M.S.406H and sent to them as pattern aircraft in late 1938 and early 1939. These examples had the earlier wing design of the 406, but were powered by the newer 12Y-31 engines.

Pre-production started with a run of eight aircraft from EKW with engines built by Adolph Saurer AG driving a new Esher-Wyss EW-V3 fully-adjustable propeller. Instruments were replaced with Swiss versions and the drum-fed MAC machine guns with a locally-built belt-fed version. The pre-production models were then followed with an order for a further 74 examples, which were all delivered by August 1940. In 1942, a further two were assembled with spares originally set aside for the original production run.

During 1943, surviving aircraft were modified with new cooling and hydraulic installations, and were fitted with ejector exhausts. These modifications were the same standard as the D-3801 series, making them identical with the exception of the engine installation. At the end of the war the remaining aircraft were used as trainers, until the last one was scrapped in 1954.

[edit] D-3801

The Swiss received the uncompleted 412 and finished it, modifying it like their 3800s with their own instruments, propeller and weapons. This was put into production in 1941 as the D-3801 with continued deliveries until 1945 when 207 were completed. Another 17 were built from spares between 1947 and 1948 and remained in service as a trainer and target tug until 1959.

[edit] Finnish variants

Finnish Morane-Saulnier MS.406, MS-325 of 2/LeLv 28, based at Viitana, winter 1941-1942

[edit] Mörkö-Morane

By 1943 Finland had received their original 30 aircraft, as well as an additional 46 406s and 11 410s purchased from the Germans. By this point, the planes were hopelessly outdated, but the Finns were so desperate for serviceable aircraft that they decided to start a modification program to bring all of their examples to a new standard.

The aircraft designer Aarne Lakomaa turned the obsolete "M-S" into a first rate fighter, the Mörkö-Morane (Finnish for Bogey or Ogre Morane), sometimes referred to as the LaGG-Morane. Powered by captured Klimov M-105P engines (a licensed version of the HS 12Y) of 1,100 hp (820 kW) with a fully-adjustable propeller, the airframe required some local strengthening and also gained a new and more aerodynamic engine cowling. These changes boosted the speed to 326 mph (525 km/h). Other changes included a new oil cooler taken from the Me 109, the use of four belt-fed guns like the 410, and the excellent 20 mm MG 151/20 cannon in the engine mounting. Supplies of the MG 151 were limited however, and several received captured 12.7 mm Berezin UBS guns instead.

The first example flew in February 1943. The results were convincing enough, giving the plane a new life and bringing it par to Soviet front-line fighters. Originally it was planned to convert all of their 406s and 410s to the new standard as soon as possible, but by the end of the Continuation War in 1944, only three examples had been converted (including the original prototype). Lieutenant Lars Hattinen (an ace with six victories) scored three kills on Mörkö-Morane. After the end of the war, the total was brought to 41, which served as advanced trainers until September 1948.

[edit] Operational history

In late '30s a war with Germany was clearly looming, and the Armée de l'Air placed an order for 1,000 airframes in March 1938. Morane-Saulnier was unable to produce anywhere near this number at their own factory, so a second line was set up at the nationalized factories of SNCAO at St. Nazaire converted to produce the type. Production began in late 1938, and the first production example flew on 29 January 1939. Deliveries were hampered more by the slow deliveries of the engines than airframes.

By April 1939, the production lines were delivering six aircraft a day, and when the war opened on 3 September 1939, production was at 11 a day with 535 in service. Production of the M.S.406 ended in March 1940, after the original order for 1,000 had been delivered to the Armée de l'Air, and a further 77 for foreign users, 30 for Finland and 45 for Turkey. Additional orders for Lithuania and Poland were canceled with the outbreak of the war.

After the armistice, Germany took possession of a large number of 406s and the later 410s. The Luftwaffe used a number for training, and sold off others. Finland purchased additional 406s (as well as a few 406/410 hybrids) from the Germans, while others were passed off to Italy and Croatia. Those still in French hands saw action in Syria against the RAF, and on Madagascar against the Fleet Air Arm. Both Switzerland and Turkey also operated the type.

The M.S.406 had a parallel career in Finland, during the Winter War and, in modified form, during the later Continuation War. Total Finnish kills amounted to 121. The top Morane ace in all theatres was W/O Urho Lehtovaara with 15 of his 42 total kills achieved in a Morane. The Finnish nicknames were Murjaani (blackmoor), a twist on its name, and Mätimaha (roe-belly) and Riippuvatsa (hanging belly) for its bulged ventral fuselage.