Categories
Cold War French Tanks

AMX-13 Avec Tourelle FL-11

France (1954)
Improvised Light Tank – 5 Built

By February 1952, the French had been fighting in the First Indochina War (1946 -1954) for six years. This war was fought between the French and Việt Minh (Việt Nam độc lập đồng Minh, Fr: Ligue pour l’indépendance du Viêt Nam, Eng: League for the Independence of Vietnam). The Việt Minh wanted to put an end to French rule and take control of Indochina. The French Minister of State for Relations with Associated States, Jean Letourneau, requested that the French Military’s latest tank, the AMX-13, be sent to Cavalry units battling the Việt Minh. The tanks equipping the Cavalry at the time – namely the M5A1 and M24 Chaffee light tanks – were too heavy and poorly armed to fight a guerilla war in a dense jungle environment.

However, the AMX-13 was also unsuitable for such warfare in its current configuration. Its large FL-10 turret and long, high-velocity 75 mm (2.9 in) gun was simply impractical for this Asian environment. There was also a requirement for air-transportability, but the AMX was just a bit too heavy to achieve this.

To meet the requirements, it was decided that modifications were needed for the AMX-13 to be suitable for constricted environments and light enough to be transported by air, thereby allowing it to be fielded in colonial policing operations, no matter the environment or enemy. This was achieved by mating the newly developed FL-11 turret – designed for the Panhard EBR (Engin Blindé de Reconnaissance, Eng: Armored Reconnaissance Vehicle) – with the existing AMX hull. This created the AMX-13 Avec Tourelle FL-11 (AMX-13 with FL-11 Turret). While it was a successful conversion that saved 1.5 tonnes (1.6 tons) of weight, the vehicle, for a number of reasons, would not go into large scale production.

The AMX-13 with FL-11 turret. This mated the hull of the AMX light tank with the turret of the Panhard EBR armored car. Photo: Pen & Sword Publishing

The AMX-13

Designed and built by Atelier d’Issy les Moulineaux or ‘AMX’, the officially titled Char de 13 tonnes 75 modèle 51 (Tank, 13 tonnes, 75mm gun, model of 1951) – often shortened to Mle 51, was more commonly known as the ‘AMX-13’. The tank was designed in the late 1940s and appeared in service in the early 1950s. It was designed to be a lightweight, highly mobile tank destroyer that could also perform the reconnaissance tasks of a light tank.

It was lightly armored, with the toughest plates being just 40 mm (1.57 in) thick. Its main armament consisted of the 75 mm Canon de 75 S.A. Mle 50, often known simply as the CN 75-50 or SA-50. The design of this gun was derived from the powerful Second World War German KwK 42 gun mounted on the Panther. The gun was mounted in an innovative oscillating turret and was also fed via an autoloading system.

The AMX weighed in at around 13 tonnes (14 tons) and was 6.36 m (20 ft 10 in, with gun) long, 2.51 m (8 ft 3 in) wide, and 2.35 m (7 ft 9 in) tall. It was operated by a 3-man crew consisting of the Commander, Driver, and Gunner. The tank went through many upgrades with many variations based on its highly adaptable chassis. The French Military only retired the AMX in the 1980s, but many other nations retain it in service.

The Standard AMX-13 Light Tank or, as it is officially known, the Char de 13 tonnes 75 modèle 51. Photo: weaponscollection.com

Fives-Lille (FL) Turrets

The engineering company Fives-Lille – shortened to FL – was responsible for the design of the turrets used on the AMX-13 series of light tanks. They were based in Fives, a suburb of Lille in Northern France.

The FL-10 turret. Note the long, high-velocity 75 mm SA 50 gun and the large turret bustle containing the autoloading system. Photo: Peter Lau, Rock Publishing

For the AMX-13 program, FL produced the 2-man FL-10 turret. This became the standard turret for the 75 mm armed Mle 51s. The high-velocity 75 mm Canon de 75 S.A. Mle 50 was fed via an auto-loading system which consisted of two revolving cylinders located in the turret bustle. It was an oscillating turret. These consist of two parts that move on a separate axis. The first is the top ‘roof’ section which holds the rigidly mounted main armament which moves up and down. In a conventional turret, the gun moves separately from the turret body, on its own trunnions. The second is the bottom ‘collar’ part attached to the ‘roof’ via trunnions and fixed directly to the turret ring, allowing conventional 360-degree traverse. The gap between the ‘collar’ and ‘roof’ could be covered with either a canvas or rubber covered material screen known as bellows. The FL-10 turret was the source of the problem for military heads that wanted the tank to operate in constricted environments, such as the dense jungle of Indochina, to provide close infantry support, not an ideal task for the SA 50. The high-velocity gun was long and, due to the autoloading mechanism, the turret bustle was large.

The FL-11 Turret

As the AMX-13 was in development, so too was the Panhard EBR armored car, which utilized a smaller oscillating turret produced by Fives-Lille – the FL-11. These turrets were manufactured alongside those destined for the EBR by Société des Ateliers de Construction du Nord de la France (SACNF, Eng: ‘Society of Construction Workshops in Northern France’) and the Société Alsacienne de Constructions Mécaniques (SACM, Eng: ‘Alsatian Society of Mechanical Constructions’).

It was decided that the FL-11 turret would replace the FL-10 on the AMX-13 hull. The FL-11 had the same level of armor protection as the FL-10 at 40mm (1.57 in) thick. The FL-11 turret was much smaller than the FL-10. This was because it lacked the bustle, due to the fact that the FL-11s gun was manually loaded.

Production diagram of the FL-11 turret. A: roof section, B: collar, C: turret basket. Note the lack of bustle and shorter 75mm SA 49 gun. Photo: Peter Lau, Rock Publications

The new gun was the 75 mm SA 49. It was shorter and had a lower velocity of 625 m/s (2050 fps) compared to the 1000 m/s (3280 fps) of the 75mm SA 50. This made the use of High Explosive (HE) shells far more effective, making the tank far more appropriate for close support tasks. The lower velocity, however, made it less effective against armored targets. Even so, firing Armor-Piercing Ballistic Capped (APBC), the gun could punch through 80 mm (3.14 in) of armor at 1000 meters (1093 yards). Secondary armament consisted of a coaxial 7.5 mm MAC31 Reibel machine gun located on the left of the main gun. Elevation range of the gun in this turret was +13 to -6 degrees. Four smoke-grenade launchers were also installed with two on each side of the ‘collar’.

The manually loaded 75 mm SA 49 gun. It was much shorter and had a lower shell velocity than the 75 mm SA 50 gun. Photo: Peter Lau, Rock Publishing

Like the FL-10, the FL-11 was a two-man turret with the crew consisting of the Commander and Gunner. However, with the lack of an auto-loader, the Commander also had the responsibility of loading the SA 49 gun. The Commander sat on the left of the turret with the gunner on the right. Both men had their own turret hatch. The Commander sat under a large cupola featuring 7 periscopes around its circumference. A mounting for an external machine gun could be installed on the cupola but, while it was used occasionally on the EBR, it is unknown if it was utilized on the AMX. The vehicle’s antennae were installed into the turret’s ‘collar’ with a base on the left and the right side.

Production diagram of the rear of FL-11 turret. Note a few details such as B: Commander’s cupola, H: Gunner’s hatch, P: smoke grenade launchers, K: ventilator, and J: stowage straps. Photo: Peter Lau, Rock Publishing

The AMX Hull

The AMX hull went through no alterations. It retained the same dimensions, as well as its forward-mounted engine and transmission. The tank was powered by a SOFAM Model 8Gxb 8-cylinder, water-cooled petrol engine developing 250 hp, propelling the tank to a top speed of around 60 km/h (37 mph). The vehicle ran on a torsion bar suspension with five road-wheels, two return rollers, a rear-mounted idler, and a forward-mounted drive-sprocket. The driver was positioned at the front left of the hull, behind the transmission and next to the engine.

Production

The conversion was approved by the French Military, with an order for 5 vehicles being placed in February 1954. One was to be built immediately for test purposes. Air transport tests then commenced in March of 1954. By May of that year, the remaining 4 vehicles had been built and troop testing was underway. At this time, an additional 15 vehicles were also ordered.

Left side view of the AMX-13 FL-11 test model. The FL-11 turret was placed on an unmodified AMX hull. Photo: chars-francais.net

Air Transportability

One of the key aspects of this conversion was to give the AMX-13 the ability to be air-transportable in the Armée de l’Air’s (French Air Force’s) cargo aircraft. The typical cargo aircraft of the Air Force’s fleet at this time was the Nord ‘Noratlas’. The original AMX-13, weighing in empty at 13.7 tonnes (15.1 tons), was too heavy. Replacing the FL-10 for the FL-11 resulted in the vehicle losing 1.5 tonnes (1.6 tons) of weight, making the new variant 12.2 tonnes (13.4 tons). This was still too heavy for the Nord, which had a load capacity of 6.7 tonnes (7.5 tons). Because of this, further tests were carried out using the larger English-built Bristol Type 170 Freighter, with a capacity of 7.9 tonnes (8.75 tons).

In the end, it was found that the vehicle was compatible with air transportation, but there was one small snag; the vehicle had to be completely stripped down and disassembled. The only way engineers could achieve the task of transporting the AMX was to take it apart and strap it down to three separate pallet loads of roughly 4 tonnes (4.4 tons) each. One pallet carried the entirety of the turret and rolled up tracks, the second carried the suspension and most of the automotive components, and the last pallet carried the entire hull unit with integral components. One aircraft could only carry one pallet, this meant that there would three aircraft to one tank, assuming three were available. If not, one craft could be making three round trips.

The AMX-13 FL-11 disassembled into three separate loads. Left to right we have the hull unit, suspension components, and the turret and track. Photo: Pen & Sword Publishing

Not only did this result in the logistical nightmare of transporting the loads, but also of reassembling the thing at the destination. This may not have been an easy task depending on the environment of said destination. The split also presented the risk of things going missing, not ideal when you need an operational tank on the front lines.

Service

Unfortunately, not much is known about the service history of this AMX-13 variant. By the time the initial batch was built in 1954, the First Indochina War had come to an end and the need for this tank had evaporated, resulting in the cancellation of the order for 15 more units.

An AMX-13 FL-11 is taken down a steep embankment. Both the driver and gunner are visible in this photo. Date and location unknown. Photo: chars-francais.net

The 5 vehicles that were built were dispatched to Morocco (still a French Protectorate in the early-mid-1950s) to be operated by the 2e Régiment Étranger de Cavalerie, (2e REC, Eng: 2nd Foreign Cavalry Regiment), a cavalry regiment of the French Foreign Legion, based in Oujda, Northeast Morocco. Their time here is not well documented, but it is known that in 1956 – when Morocco gained independence – the tanks were sold to the fledgling Moroccan Army. Details of their service here are also unknown. They were still present in the Moroccan arsenal in 1973.

There is a possibility that the Moroccan Army used the tanks in combat. In 1963, Morocco fought a border war with Algeria – the ‘Sand War’. Morocco fielded AMX tanks in that conflict, so the FL-11s may well have been among them.

In a typically French fashion, the crew (the three closest to the tank) of this AMX-13 FL-11 relax with what appears to be a bottle of wine next to their vehicle with an unknown guest. Date and location unknown. Photo: chars-francais.net

Conclusion

It is currently believed that no examples of the AMX-13 Avec Tourelle FL-11 survive today. How long they served and what happened to them in Morocco is currently a mystery.

This variant of the AMX-13 highlights what can happen when tanks that are designed for a specific purpose arrive too late to serve that purpose. They become destined to see out their service in obscurity, never having the chance to prove themselves in combat. The vehicle was also a bit of a failure when it came to the illogical air-transport element of its design. A feature that was one of its most important aspects. Despite this, however, the vehicle was a stepping stone to more French experiments with the concept of an air-transportable tank. These experiments would lead to the ELC EVEN and AMX-ELC programs.

As for the FL-11 turret, that too was destined for a short service when it came to its initial host, the Panhard EBR. Numerous upgrade programs were undertaken during the EBR’s service life. Early programs resulted in the 75 mm gun being replaced with a short 90 mm gun, while later programs saw the FL-11 completely replaced by the AMX-13’s original turret, the FL-10.



The AMX-13 Avec Tourelle FL-11. This was a mating of the AMX’s 13-tonne light tank and the Fives-Lille FL-11 turret, more often found on the Panhard EBR. Illustration by Tank Encyclopedia’s own David Bocquelet, modified by Andre ‘Octo10’ Kirushkin.

Specifications

Dimensions (L-W-H) 6.36m (4.88m without gun) x 2.5m x 2.3m
(20’9″ (16’0″) x 8’2″ x 7’5″ ft.in)
Total weight, battle ready Aprx. 15 tons
Crew 3 (Commander, Gunner, Driver)
Propulsion Renault gasoline, 8-cylinder water-cooled 250 hp
Suspension Torsion arms
Maximum speed 60 km/h (40 mph)
Range (road) 400 km (250 mi)
Armament 75 mm SA 49
7.5 mm MAC31 Reibel machine gun
Armor Hull & turret 40 mm (1.57 in)
Production 5

Sources

M. P. Robinson, Peter Lau, Guy Gibeau, Images of War: The AMX 13 Light Tank: A Complete History, Pen & Sword Publishing
Peter Lau, The AMX-13 Light Tank, Volume 2: Turret, Rock Publications
Olivier Carneau, Jan Horãk, František Kořãn, AMX-13 Family in Detail, Wings & Wheels Publications.
R. M. Ogorkiewicz, Profile Publications Ltd. AFV/Weapons #39: Panhard Armoured Cars
National Intelligence Survey #48, Morocco; Armed Forces, March 1973.


By Mark Nash

Member since 2016. Specializes in weird. 113 articles & counting...

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