Sd.Kfz.3 Opel Maultier
Nazi Germany (1942-44) - Utility Half Track - circa 8,000 built
The Open Maultier was the conversion of the proflific and trusted German Opel Blitz to a track system to cope with the conditions on the eastern front in WW2. In the end, 22,000 of these utility Half Tracks (combined with Opel, Magirus and Benz conversions) would be produced/converted, declined in armored or specialized bodies, and some later also used as FLAK 38 carrier vehicles.
Genesis
In the summer of 1941, the Wehrmacht launched the largest invasion of history, called "Operation Barbarossa". Based on previous campaigns based on speed, using new tactics and new organization setup to take advantage of modern communication and on-demand air support, 180 Panzerdivisions ploughed forward, with the Panzerdivisions as fulcrums, to brush aside an estimated 50-75 good Soviet ones Divisions, but their resilience combined with the vastness of the Soviet area had been underestimated. Victory escape the OKH by the autumn of 1941, as motorized formations were literally stuck in the mud.
Indeed, after invading the USSR, German troops discovered that their wheeled vehicles, trucks and cars, proved unsuitable for the ingrate Russia network, particularly during the infamous "rasputitsa season". There were indeed two periods during each year which transformed all non-paved roads ("dirt roads") into quagmires of knee-deep, sticky compact mud, that trapped all but the most specialized wheeled vehicles. So basically this network extended between nearly all localities outside Moskow and the western largest cities, and outside of reach of the train, and only the summer and winter seasons when the roads were hard enough to be practicable again, the supply train of the panzerdivisions could advance again.
Without this vital bloodline, Hitler's mighty Panzers were starved of fuel and ammunitions, especially in the context of "scorched earth" ordered by Stalin. This was the main reason behind the failure of the central front to reach and take Moskow, the ultimate prize, and why the offensive bogged down until it ws decided to consolidate an immense frontline, running from the Baltic to the black sea. Only tracked tractors and half-tracks were able to supply the Wehrmacht but they were too few, even when bolstered with many captured Russian tractors, but the latter broke due to a lack of spare parts. Meanwhile, all matter of trucks, prevoious forcibly seized in occupied countries, were thrown into the supply carousel whatever the cost: Belgian, Danish, Dutch, French, even Polish trucks designed for well paved roads, became stuck, and an easy target for the enemy, ending all as losses. To avoid this, every conceivable tracks vehicle was used for towing supplies, but they lacked to operations.
The best German infantry fighting vehicles that were the Sd.Kfz.250 and Sd.Kfz.251 half-tracked used the Sd.Kfz type.10/11 chassis, and production were linked. Indeed, at the time, half tracks like the Sd.Kfz.11, already available in numbers, could haul supplies to forward units, coming from rearwards supply bases where the trucks ended in best conditions, but could not go further. It was like attempting to fill a pool with a spoon. The problem is that these hald-tracks were missing to the units that needed them, which depended on them for their combat role. One possible option was to massively increase production of the Sd.Kfz.11, all or any suitable model, although these were costly. Right away, first prospects for a universal, simpler, cost-effective platform was looked after.
The other, simpler, cheaper and faster solution was to adapt was the standard Opel Blitz, Daimler-Benz, but also Alfa-Romeo and Ford lorries into half tracks by removing their rear axles, which ibliged to truncate their prop-shafts, connecting them to redundant Panzer I track assemblies. Heavier trucks (4 tons payload) would be converted the same, but on Panzer II track assemblies.
The current Horstmann suspension components of the Panzer I were pretty close to the track system used on the British Universal Carrier, and so the Maultier early prototype ironically closely resembling the roadwheel/suspension system of the T16, US production version of the "Bran Carrier". Most Maultier conversions used as a base the readily available Opel Blitz model S, quite successful in service already. Still, the final product as tested lacked the overall mobility of purpose-built half tracks but they came as a cost-effective solution, and proved their worth on difficult terrain, doing far better than usual trucks. From 1943 some of the Opel Maultier were also armored, resulting in the Sd.Kfz.4 Panzerwerfer 42 as Sd.Kfz.4/1 but it was the exceptions. Other of the Maultiers were converted, mostly on the field, to carry an AA gun mount, 20 mm in general, as ad hoc extra defensive asset.
Development
2 ton track truck:
Under the leadership of Dr. Hähnlein, special committee "Maultier" ("Mule") was formed in 1942, discussin the development and production of a supply half-track truck. Various projects were taken as inspirations, such as between 1937 and 1938 the Daimler-Benz LR 75 intended for civilian use. However (25 built). But it was never designed for mass production. The team soon realized that the construction or conversion must met the standard format of the 3-ton class truck, the most common in 1942 records , as a the starting point. It was estimated that 4x4 vehicles should be kept in rear echelons conversion should convcern the road-only 4x2 vehicles. The study pointed at the Opel Blitz 3.6-36 as the ideal basis, although the equally numerous Magirus S 3000, the Ford V 3000 S and Mercedes L 4500 S were considered.
Once contacted with a set of requirements, Opel developed an independent track chain system, entirely swapping the rear axle by a yet-to-be defined track system. The interesting bit was the way it was made modular, in order to reproduce the conversion to any of the models specified above. They designed a shortened drive shaft with front drive wheels driven via an axle, with differential. They created their own tracks, with two pairs of movable wheels providing with leaf springs suspensions as running wheels, deflection roller set low, over which were installed the Panzerk I track system, which ran over two support rollers.
The Waffen-SS also looked at a similar solution in the winter of 1941/42, esxperimentally fitting some Ford trucks in the field with a rear running gear from captured British universal carriers in north africa. They also converted in this basis Opel chassis, and they went through extensive testing in Berka, by the Army Weapons Office. The latter reported in the end that the Opel design was a preferrable base, bringing several advantages over the Ford model, although the gearbox was problematic, but the problem could be solved. In the end, only the chassis was modified along the the Waffen SS version. The vehicles received the type designation /SSM (like Ford V 3000 S/SSM) to indicate clearly the chassis modified by themselves.
Daimler-Benz L 4500 R
From 1939 Daimler-Benz started production of the L 4500 S type for the Wehrmacht which was later modified as an all-wheel-drive variant L 4500A in 1941. The appearition of the KV-1 and T-34, imprevous to all existing German ordrnance, force the adoption of 8.8 cm armed tank-hunters. The lack of towing vehicles, notably with the delayed program to replace the 5-ton tractor Sd.Kfz.6 led the ordnance bureau to ask Daimler-Benz and Büssing-NAG to equip their heavier 4.5 t series with a caterpillar track aft. Both companies submitted their own designs, Daimler winning an order for 600 vehicles, adapting the Panzerkampfwagen II chassis to theor L4500 S truck with the first delivered in August 1940 and in 1944, 1,480 vehicles being produced.
Design
Chassis and general design
The present article is about the "Opel Maultier", further articles will detail the other Ford, Magirus and Mercedes-Benz variants of the Maultier in the future. As for the Opel Maultier, it was very much the same factory-stock vehicle, which was its main interest, measuring 6 meters () for 2,28 m in width and 2,05 m in height (top of the cab's roof), but taller when the tarpaulin was framed, and some specialized versions were even taller.
The greatest change are describe above, concerning the rear drivetrain, inspired by the T16 own interpretation of the Hortsmann's roadtrain and suspension system, with a shortened drive shaft, front drive wheels driven via an axle with differential and other perks. The rera drivetrain was fixed and direction could be obtained only by the front axle, but also blocking one or the other track thanks to the differential. The vehicle weighted 3,9 tonnes, notably more than the original Blitz.
Powerplant & Performances
Like the basic Opel Blitz, the Maultier had the same six-cylindres Opel/Blitz 3,6 liters, rated for 68 hp at 3 000 rpm. It was coupled with a 5-speed transmission and reverse gear. The suspension combined the leaf springs of the front axle and halftrack part comprised torsion bars. Performances-wise, the Maultier was less agile and fast compared to the regular 2x4 Blitz, with a top speed of only 38 kp/h (), and the range was 160 km on flat, 80 km off-road, based on the 82 liters tank, consumption was 50 liters for 100 km and off-road twice that amount. In some ways, the vehicle could be seen as the "last leg" truck, assuming the loads had been transferred from regular trucks, up to the mud-clogged frontline.
2 cm Flak 38 auf Halbketten-Lkw Opel "Maultier"
The basic Maultier had the same flatbed as the original Blitz, with a frame and wooden paneling, folding sections and three main bow frames for the tarpaulin. Some had a different panel design, complete uo to the top, but both were relatively tall, going up to the cabin's rooftop. Technically the Maultier was always unarmed, to the exception of the crew's own weapons. However there is a documented use (through many photos) of the verhicle's conversion into a FLAK truck, carrying on its flatbed the FLAK 38, 20 mm autocannon. The flatbed was roomy enough to traverse the shielded gun 360°, and thus present its barrel either forward or aft.
The Flakvierling 38 was first developed in 1934, and more than 144,000 (but 40,000 FLAK 38) were delivered to the Wehrmacht and Kriegsmarine as well, becoming an ubiquitous close-in defence system. The fixed mount (no wheeled carriage as for the FLAK 30) weighted "only" 405 kg (893 lb), so light enough and small enough to fit on the Opel Maultier's flatbed, which was modified to have the walls folding down around and create a walkway fo the crew of 5, including the commander, gunner and loaders. The FLAK 38 had an Effective firing range of 2,200 m (2,406 yds) in anti-aircraft used and beyond 5,700 (5230 yards) on ground use.
Since the conversion is not well regulated, it's hard to tell how many of these conversions, always possible in the field, were done.
⚙ specifications |
| Displacement | 3,930 kgs (8,660 Ib) |
| Dimensions | 5.95 x 2.25/2.28 x 2.05/2.1 m (see notes) |
| Propulsion | Opel 3.6-litre 6-cyl petrol engine |
| Speed | 38 km/h (24 mph) |
| Range | 160 km (), see notes |
| Armament | None but 2cm FLAK 38 for specialized variant |
| Crew | 2 |
Designation
In order to achieve sufficient production figures for track chain tractors, various manufacturers were involved in production as described above:
Sd.Kfz.3a: Opel Maultier, Brandenburg plant
Sd.Kfz.3b: Ford Maultier, Cologne
Sd.Kfz.3c: Magirus Maukltier, Klockner-Humboldt-Deutz (KHD)
Sd.Kfz.3/4: Ambulances (all brands) Ford/Opel chassis
Sd.Kfz.3/5 or Sd.Kfz.4 Mercedes 4.5 t Maultier
Sd.Kfz.4: Armoured Panzerwerfer 42 variant.
-In the type designation for the 4.5-ton Mule from Daimler-Benz[6], but this vehicle is also known as the Sd.Kfz. 3/5 denoted.
-In the form "Sd.Kfz.4/1" for the 15 cm Panzerwerfer 42 on a self-propelled gun, which after the official introduction is listed as the 15 cm Panzerwerfer 42. There was a variant of this vehicle as an ammunition tractor, which carried the same special vehicle number (Sd.Kfz. 4/1) and could be converted to a launcher at any time if necessary.
The Opel Maultier in Action
The Maultier was specifically tailored to withstand the specific terrain and road conditions of the Eastern Front, during the wet seasons. Assignments were thus, exlcusively to the East. These vehicles took over the task of the regular trucks to supply ammunition and food to the frontline. They also served as towing vehicle for light artillery units of infantry units, but also acted as troop transport, and for specific equipment like mines or barbed wire amonf others, and transporting the wounded (in a specialized variant). However by 1943, ammunition supply became the most important task. Motorized formations and Panzerdivisions, as well tank destroyers and assault gun units, were often assigned a squadron of six Mauliers each.
They were often used as a replacement for the Sd.Kfz.10/11 issued until then, freed to be armed and used as offensive support or motorized FLAK. From 1943, some units towing the 7.5 cm Pak 40, 7.62 cm Pak 36, 10.5 cm light field howitzer 18 and also 12 cm grenade launchers were assisted also with Maultiers. It's the larger 4.5 tons Mercedes/Magirus Maultier that became the main tractor for the 8.8 cm anti-tank gun. The Luftwaffe also received these vehicles for mobile units, transformed with 2 cm FLAK 38 but in some case also even the 3.7 cm AA gun, mounted on the flatbed. They were thus, immediately ready to fire on the march. The 1.5 tons 3.7 cm FLAK 36/37 plus equipment, ammunition and crew made for a hefty payload, aggravating the wear and tear of the carrier vehicles.
There were rare cases of specialized cabin superstructures, individual wooden structures that were standardized at bodyworks companies, with typical uses being the medical vehicles (Sd.Kfz. 3/4), radio and workshop vehicles sharing more of less the same. The flatbed was removed to fit in place the standardized box body, which was modular inside and had up to five doors and six windows.
Production
The proverbial tracked truck of the German Army tailored for the condition of the Russian network saw some 20,945 manufactured from 1941 at Klöckner-Humboldt-Deutz AG and Ford factory at Asnière (France). The supply bureau ordered the conversion of the standard Opel, Daimler-Benz, Alfa-Romeo and Ford trucks and side Panzer I track assemblies the standard "Mule" also used standard Horstmann suspension components coupled with the Opel Blitz model S.
In 1942 a total of 635 had been delivered and by 1943 13,000, but by 1944 only 7,310 notably due to bombardments and also the decision to develop and "universal" half-track platform.
However sources differ greatly on the number of manufactured Opel Maultiers. Oswald stated only 4000 Opel Blitzes had been converted, which added to the other brands, is coherent with the total of 21,945 and this is conformed by Spielberger, again 4,000 Opels, (as well as 14,000 Fords, 2,500 KHDs). Baschin confirmed this figure of 4,000 Opels, but the total cited is always independent from the manufacturer's details. Contradictory information may be partly related to the fact the Opel Maultier were created by converting existing trucks at the Oranienburg motor vehicle testing department and a letter of May 14, 1943, started that a total of 700 vehicles sold by the Opel plant in Brandenburg to Oranienburg from August to December 1942 are cited, of which 450 are converted at Stoewer in Stettin or Auto Union in Spandau. By November 1942, 35 vehicles, by December 1942, 156 vehicles only are accepted by the Wehrmacht. To also add to the confusion, there were several specialized bofies made both for the Opel and Ford conversions, like radio post, medical post or repair unit, workshop, etc. And this was done further down the line after their with vehicle manufacturers reporting these vehicles as finished but not accepted by the Wehrmacht before the bodywork (by B. Gaubschat) was not complete.
Production figures from the Federal Archives is only dated back from November 1943, and there are gaps in the figures for the collection from the Federal Archives for 1942 and January 1943 as only Opel kept separate statistics for the purchase of the Maultier. By November 1943, the manufacture at KHD was terminated and in 1944 no more of these conversions were made. From August 1944, acceptance of Maultier conversions is no longer differentiated according to manufacturer from regulat trucks. On August 6, 1944 the Opel factory in Brandenburg notably was hit hard by a bombing raid and production stopped until the end of the war. It went on only for Ford (France Plant) but as the front moved and the Wehrmacht was pushed back from Russia and back to "normal" road networks, the Maukltier was noi longer needed and production stopped altogether, the later vehicle being more often converted to specialized roles and notably FLAK vehicles. Manufacturers returned to normal truck production, cheaper, simpler, with a better payload, less consumtion and better speed. The wear of these drivetrain was also higher due to additional loads not previously planned for these particular systems.
At KHD plant a total of between 1740 and 1750 Maultier were made depending on the source and discrepancies in numbers are linked to the KHD S330 and S3000. Spielberger stated 2500 are too high and unsourced while Oswald underestimated this and in the end states at least 8055 Opel Maultier were made, all plant combiend, and probably a few more, with extra conversions at Spandau and Stettin and in several body manufacturers. The most reasonable figure of 8250 at mor or less 50 vehicles is a safe bet. Over these, the bulk waere done in 1943 (4,055) and circa 4,000 in 1944, but including the armored rocket launcher conversions and supply vehicles (427 in 1943, 120 in 1944).
Links about the Sd.Kfz.3 Maultier
Books
Chris Bishop (Hrsg.): Waffen des zweiten Weltkriegs : eine Enzyklopädie. über 1500 Waffensysteme: Handfeuerwaffen, Flugzeuge, Artillerie, Kriegsschiffe, U-Boote. Dt. Erstausg. Auflage. Bechtermünz, Augsburg 2000
Philip Trewhitt: Panzer. Die wichtigsten Kampffahrzeuge der Welt vom Ersten Weltkrieg bis heute. Neuer Kaiserverlag, Klagenfurt 2005
Werner Oswald: Kraftfahrzeuge und Panzer der Reichswehr, Wehrmacht und Bundeswehr. Motorbuch-Verlag, Stuttgart
Vorschrift D 666/408 Gleisketten-Lastkraftwagen 2 t (Maultier), Klöckner-Humboldt-Deutz A.G., Baumuster S 3000/SS M 1943.
Joachim Baschin: Gleisketten-LKWs „Maultier“ Sd.Kfz. 3 / Nuts&Bolts Vol. 28. 1. Auflage, Nuts&Bolts Verlag GbR, Neumünster 2011
Walter E. Seifert: Die Kfz-Nummern der Deutschen Wehrmacht, Riesa 2010
Hahn, Fritz: Waffen und Geheimwaffen des deutschen Heeres 1933-1945, Band 2: Panzer und Sonderkraftfahrzeuge
Links
Production records - babel.hathitrust.org
on wikipedia
On materielsterrestres39-45.fr