The Lorraine 37L or Tracteur de ravitaillement pour chars 1937 L, (Tank Supply Tractor 37L) was a light tracked armoured vehicle developed during the Interbellum by the Lorraine company to a French Army requirement.
Early 1937 the Lorraine company finished a prototype. It was a lengthened version of a proposed replacement type for the 1931 model Renault UE Chenillette tracked infantry supply tractor. In February 1937, the matériel commission, the Commission de Vincennes, was ordered to test the prototype and to finish an evaluation before 1 November 1937, even if testing would not yet have been finished. The prototype was only presented on 9 July and tested until 4 August. Although the vehicle attained a maximum speed of 30 km/h, this dropped to an unacceptably low 22.8 km/h when an intended fuel trailer was attached. It was therefore returned to the factory; after a stronger engine and clutch had been fitted it was again tested between 22 September and 29 October and now achieved the desired 35 km/h.
In 1938 three orders were made, of 78, 100 and another 100 vehicles of the Tracteur de ravitaillement pour chars 1937 L (TRC 37L); in 1939 before the war a fourth order followed, of 100, and a fifth of 74 to which was added the replacement order of 100 for a total of 552. The first vehicle was delivered by Lorraine at 11 January 1939; 212 had been delivered on 1 September 1939.
The ambitious plans made after the outbreak of war for the expansion of the number of armoured divisions meant that the Lorraine 37L orders had to be enlarged accordingly, bringing the total to 1012 with an intended initial production rate of fifty per month, to be expanded to seventy. To assist in the manufacture a second assembly hall was erected by Fouga at Béziers of which it was hoped that it could produce, at first twenty and later thirty vehicles per month. In reality this number was never attained; e.g. twenty were made in January, 32 by both companies in May 1940. At 26 May 1940 432 vehicles had been delivered by Lorraine and Fouga out of 440 produced. Production continued after that date and an estimated total of about 480 had been reached by 25 June 1940, the end of the Battle of France
Given the vehicle's low weight, the suspension is quite robust and exceptionally reliable in comparison with other systems used on French armour of the time, that were either too complicated or too flimsy. Six large road wheels in three bogie pairs ensure a low ground pressure and good weight distribution. Each bogie is allowed a vertical movement in its entirety, springed by an inverted leaf spring assembly located just below the upper track run, the three assemblies being placed between the four top rollers. The tracks are 22 centimetres wide. The drive sprockets are in the front and driven by a transmission in the nose of the vehicle. Two crew members, the driver on the left, can be seated in the driver compartment, the drive shaft between them. Entrance to the compartment is offered by two wide horizontal hatches, the upper hinging upwards, allowing the driver an unobstructed view if opened, the lower hinging downwards.
Behind the driver compartment is the engine compartment separated by a bulkhead. On the left outside of the compartment is a silencer with an armoured covering. All vehicles in the series were powered by a Delahaye Type 135 6-cylinder 3.556 litre engine developing at 2800 rpm, giving a maximum speed of 35 km/h. The wading capacity is 60 centimetres, a trench of 130 centimetres can be crossed, an incline of 50% climbed. There is a fuel supply of 144 litres, allowing for a range of 137 kilometres.
At the back is an armoured bin to transport ammunition; a load of 810 kilogrammes can be carried bringing the weight to 6.05 tonnes. As with the Renault UE, the TRC 37L is supplied with a tracked, armoured trailer with two road wheels per side, mostly used to carry a 565 litres fuel tank to supply the tank units; total load capacity is 690 kg for a total for the combination of 1.5 tonnes and a total weight of the trailer of 1890 kg. The trailer is somewhat narrower than the main vehicle, at 155 cm and higher at 133 cm. The trailer also carried a Vulcano fuel pump and stowage boxes for lubrication oil, greases, water and assorted equipment to serve the tank maintenance teams.
The situation changed in the late thirties. Having at last built a considerable number of modern and well-armoured tanks, the Infantry became confident in its ability to break the enemy line, if sufficient artillery and air support was provided within a combined arms tactic. At the same time the political situation made it likely that large-scale offensives were needed to bring Germany to its knees. Though few officers advocated the creation of armoured divisions able to execute both the breakthrough and the strategic exploitation phase — these required trained personnel in numbers that simply would not be available — it was understood that the "manoeuvre mass" of tanks effecting the break would immediately have to envelop the defensive enemy position and defeat counterattacking enemy armour reserves, otherwise the momentum of the attack would be lost and the breach would not be kept open long enough for the motorised divisions and Cavalry armoured divisions to be launched to quickly occupy and hold strategic key positions.
However, this posed a serious logistical problem: trucks would not be able to closely follow the tanks on the battlefield. The prescribed procedure for resupplying was for the tanks to return to their start positions to be refitted. While this had still been practical in the previous war with its much slower tempo of operations, it was unacceptable in modern warfare. The tanks would have to be supplied in the field to continue their advance as soon as possible. Thus a tracked supply vehicle was needed that could overcome the expected poor terrain conditions, with many shell-craters and trenches, and it had to be armoured to protect against shell-fragments, given that the breakthrough sector would likely be in range of concentrated enemy artillery.
The type was provided to both the armoured units of the Infantry and of the Cavalry. Each independent tank battalion of the Infantry, or Bataillon de Chars de Combat, had an organic strength of twelve Lorraine tractors: four in the peloton de reserve (supply platoon) of each of its three companies. The BCCs incorporated in the armoured divisions and equipped with the Char B1 or Char B1 bis had however 27 TRC 37Ls: each of their three companies had six tractors in its supply platoon and furthermore a single tractor organic to each of its three tank platoons. This extra allotment was made to compensate for the large fuel consumption of these heavy tanks, that, apart from from being simply bigger, had also a rather limited range. Each group of three tanks was in their case thus directly followed by its own fuel supply.
When during the Battle of France independent companies were formed these too had their four Lorraine tractors — or a reduced allotment of eight if a Char B1 bis unit. However, the older FT 17 battalions did only use fuel trucks. Likewise the TRC 37L was not in common use in the colonies; but when the 67e BCC, equipped with the Char D1, was in June brought over from Tunesia, it was yet provided with tractors. The Mechanised Infantry Divisions did not use the TRC 37L.
In the Cavalry each squadron of twenty tanks had three Lorraine tractors, for a total of 24 for each Mechanised Light Division. The AMR 35 or Panhard 178 units did not use the type, but trucks only, as its speed was considered insufficient. It was proposed to remedy this by fitting a stronger engine, bringing the speed to 50 km/h. The TRC 37L was also not present in the Cavalry Light Divisions.
In practice the supply vehicles would mainly move by road and meet with the tanks at predetermined rendez-vous points. Refuelling was relatively quick as the Vulcano could theoretically pump 565 litres in fifteen minutes. To completely refill a heavy tank would normally take about forty to sixty minutes. The trailer fuel reservoires could themselves be replenished by the company fuel truck carrying 3600 litres of petrol. The company supplies could again be restocked from battalion stocks, moved by trucks loaded with fifty litre fuel drums. This method of distribution ensured a sufficient fuel supply on the tactical level, but was too cumbersome for strategic movements: if large distances had to be covered on track, the tanks would be directly refuelled from fuel trucks.
When the Germans invaded on 10 May, French tank units had an organic strength of 606 Lorraine 37Ls; the numbers produced were thus insufficient to provide each unit with its official complement. About a third had to do without. That day French General Headquarters decided to increase the TRC 37L strength of 1e and 2e DCR with a half; these armoured divisions had been earmarked as reserves against an expected German breakthrough attempt in the Gembloux Gap and the low range of the Char B1 bis worried French command. To free enough tractors, 3e DCR, still in the process of being constituted, had to give up its twelve TRC L37s to 1e DCR. Ironically, the main German breakthrough would be at Sedan and 3e DCR was sent to block it — and despite its larger number of fuel tractors, 1e DCR would still on 15 May be surprised by 7. Panzerdivision while refuelling.
During the campaign the crews of TRC 37Ls quickly saw the need for some armament and began to improvise machine-gun mounts on their vehicles.
The first development from the TRC 37L was an armoured personnel carrier, the Voiture blindée de chasseurs portée 38L ("Armoured mounted infantry vehicle 38L"). Like the TRC 37L, this Lorraine 38L was equipped with an armoured tracked trailer. The total capacity was twelve men: the driver and one passenger in the driving compartment, four in the former cargo bay, and six in the trailer. To protect the infantry squad, high box-like armoured superstructures were built over both the bin and the trailer, with doors at their back. A total of 240 VBCP 38L vehicles were ordered, of which nine had been delivered on 1 September 1939 and around 150 by 25 June 1940. Of all participants in the Battle of France, the French army would thus be the only to employ a fully tracked APC. The vehicles were intended for the Bataillon de Chasseurs Portés, the (single) mechanised infantry battalion within the Division Cuirassée de Reserve, or armoured division of the Infantry. On 10 May they had however not yet been allocated to these units, who still used half-tracks.
An improved model, the VBCP 39L, was created by expanding the cargo bay to carry eight passengers. This model had no trailer and a total capacity of ten persons; extra room was found by raising the upper deck — the passenger compartment was open-topped — and constructing a more forward sloped armour glacis, contiguous with the nose section; the type thus resembled postwar APCs. Some two hundred VBCP 39L vehicles were ordered, but none had been delivered by June 1940. Experimental and limited production models included tank destroyers armed with 47 mm SA 47 guns (Chasseur de Chars Lorraine) and command post vehicles.
A considerable number of Lorraine tractors, about 360, fell into German hands. Due to its reliability, the type was well suited to the mobile tactics the Germans favoured in 1941 and 1942. They were first used as such, renamed the Lorraine Schlepper (f). As the Germans themselves had not produced a similar type, the Lorraine tractors filled a requirement for fully tracked supply vehicles as Gefechtsfeld-Versorgungsfahrzeug Lorraine 37L (f) or Munitionstransportkraftwagen auf Lorraine Schlepper. In July and August 1942 for the German Army a number of 170 were converted into the 7.5 cm PaK40/1 auf Geschuetzwagen Lorraine Schlepper (f) or Marder I, a 75 mm tank destroyer. At the same time 106 were converted into self-propelled artillery: 94 into the 15cm sFH13/1 (Sf) auf Geschuetzwagen Lorraine Schlepper (f) and 12 into the 10.5cm leFH18(Sf) auf Geschuetzwagen Lorraine Schlepper (f). Also an artillery observation vehicle was provided: the Beobachtungswagen auf Lorraine Schlepper (f), thirty of which were produced. A single conversion entailed the fitting of a Soviet 122 mm howitzer: the 12.2cm Kanone (r) auf Geschuetzwagen Lorraine (f).
For a time it has also been assumed that a 47 mm tank destroyer conversion existed: the presumed "4.7cm Pak181(f) auf PanzerJäger Lorraine Schlepper (f)", based on preserved photographs that however in reality depicted the French Chasseur de Chars Lorraine mentioned above, an ad hoc conversion built in June 1940.
The Germans also employed the VBCP 38L as Lorraine 38L(f).