M39 Pantserwagen - Description

Description

In designing the DAF M39, Van Doorne deliberately strived for modernity. A traditional construction based on some pre-existing truck chassis was unacceptable for that reason alone. A brandnew design however, also had the advantage of being able to apply the most weight-efficient configuration. Partly this was achieved by a welded monocoque design that needed no heavy chassis girders, but also by the use of sloped armour, that could approach the ideal envelopment of a given inner space. This was most apparent with the Pantrado 2 design that used many facets to approximate the desired curvature. This would have worked even better through the use of cast armour, but casting would have been too expensive. In fact that was even true for the complex form of the Pantrado 2; the Pantrado 3 therefore showed a simplified hull shape, reducing the number of welds; a comparison has been made with the T-34 design. In cross-section the hull was essentially a hexagon and the intersection formed by the truncating glacis, or sloped frontal plate, was therefore hexagonal too. This was somewhat obscured by the fact that this glacis gradually merged with the front fenders. The front glacis connected to the bottom plate via a narrow strongly curved section. The back plate too was hexagonal but more reclined; it was at its underside joined to a lower back glacis plate, both forming a wedge. The upper and lower side plates also formed wedges.

Internally there was a single large inner space, lacking bulkheads separating the driver positions at both ends from the fighting room in the middle. This not being cluttered with girders, the most efficient position for the mechanical parts could be chosen, further decreasing weight and height. In the front the driver was seated on the left with the machine-gunner at his right. As there was a dual drive capacity, a second driver in the rear could immediately reverse the vehicle in an emergency situation without making a turn; he also could operate the rear machine-gun. To his left was the engine, enclosed by asbestos-reinforced bulkheads that formed a small engine compartment; these could be quickly removed to allow for repairs without leaving the vehicle. The engine could be accessed from the outside through a small subrectangular hatch in the roof or a large double hatch on the back that also provided ventilation, the slits being protected by conspicuous raised longitudinal covers. As the vehicle was largely symmetrical, it was not always easy to tell the front from the back, especially if the turret was reversed. This Landsverk turret was slightly less modern in appearance, in the form of a truncated cone; the turret originally designed for the Pantrado 2 had been lower and sleeker. In it were the commander and gunner, bringing the total number of crew members to five.

The DAF M39 was a rather compact vehicle, 4.75 metres long, 2.22 metres wide and 2.16 metres high. The width of the armoured hull as such, without fenders, was 2.08 metres and its height without turret 1.60 metres. Track width was 1.73 metres for the front wheels and 1.81 metres for the rear wheels. The general ground clearance was forty centimetres but just 31 cm at the rear axle. It could wade though sixty cm of water. The car had two doors, one at each side. In addition each driver had a circular hatch in the roof of the hull and the turret had a circular hatch in the roof and two large side hatches. A side hatch was also available to the back driver. Ventilation for the main compartment was provided by an armoured ventilation grid on the right side, that however only sucked in air when a hatch in the engine bulkhead was opened. All doors and hatches were made gas-tight by the use of rubber rebates.

The armour was light, just enough to defeat light machine gun fire. The front side and back plates had a thickness of 10 mm (0.39 in). Due to differences in angling the effective protection varied though: the back, sloped at about 30°, was the best protected area with a line-of-sight thickness of about 20 mm, to which a certain deflection effect should be added. The 45° front glacis had an effective thickness of about 14 mm; the sloping effect of the side plates was negligible. The top had a thickness of six, the bottom of five millimetres. Several conventional designs, the M36 and M38 included, did not even have bottom armour. The fenders too were made of armour steel, four millimetres thick. The Swedish turret had a lower armour basis: its walls were 7.5 mm thick, its roof five. The small size and light armour resulted in a relatively light vehicle with a loaded weight of somewhat over six metric tonnes. The pressure was evenly divided over the wheels, the rear axle bearing four and the front axle two tonnes. Additional protection was provided by two portable fire extinguishers, one of the dry powder type, the other using carbon tetrachloride.

The main armament was in the turret, consisting of the semi-automatic Bofors 37 mm Long 34 cannon, that the Dutch called the 4 paw. Though the DAF M39 was primarily intended as a reconnaissance vehicle, the Dutch Army was painfully aware it lacked any heavier armour to back it up, so an armament had been chosen with an adequate antitank-capacity for the period. The Bofors 37 mm L/34 could defeat almost all German armour in use on 10 May 1940 and the M36, 38 and 39's carried the largest calibre of all armoured cars on that date operational on the Western Front. For the gun a APHE and a HE round were available. The specifications of 1937 detailed that the ammunition stock should be no less than a hundred. The gun had an elevation of 23° and a depression of 9°30°°. Optionally coaxial was a Lewis 7.92 mm machine-gun to the left of the cannon that could be decoupled and then was movable within a cone of 30°. It was specially modified, increasing the original 6.5 mm calibre, and called the M. 20 no. 2. Elevation of the main gun and traverse of the turret were by hand. The commander, sitting on the right, had to load the main gun; the gunner to his left loaded the machine-gun. The commander had a periscope having a magnification of 2.5 and a field of view of 28°. The gunner had a (non-rotatable) episcope, also serving as gunsight, with a magnification of 1.75 and a field of view of 40°.

The remainder of the armament consisted of the two hull machine guns, one in the front plate, the other in the back plate. They were placed in ball-mounts attached to protruding sections welded to the plates. They too were movable within a cone of 30°. They were of a slightly different modified 7.92 mm Lewis type called the M. 20 no. 1. The rear machine-gun could be removed and placed in a special mount on the turret roof to function as an anti-aircraft weapon. All three machine guns mounts were extended with a special long armour sleeve to protect the cooling aluminium barrel-casing, typical of the Lewis gun. The specifications asked for a stock of 4,000 rounds of machine gun ammunition; also pistols and twenty hand-grenades should be present.

For external communications it was intended to equip all vehicles with a radio set. For this it would have been necessary to rebuild the turrets, attaching a bustle at their back, to place the sets in. No vehicle had yet been so modified in May 1940. The commander could also give light signals to vehicles behind him by means of a small signal lamp placed on a small pedestal at the back of the turret. For internal communications he could use an electrical-optical installation, allowing him to give orders to the drivers by pushing one of four buttons: "Drive Forward", "Forward Halt", "Drive Backward" and "Backward Halt", causing the corresponding orders to light up on the respective driver consoles. The driver could more mundanely communicate with the outside world using a vehicle horn.

The engine, a liquid-cooled Ford Mercury V8 3.9 litres 95 hp, made a maximum speed of about 75 km/h possible. There were three forward gears and one reverse. An auxiliary gearbox, placed behind the engine, functioned as reversing device and allowed for the dual drive capacity: the rear driver could use the same gears as the main driver. However, the maximum speed in the reverse direction was, for safety reasons and because the back drive system had been deliberately made less robust to save weight, indicated by the manufacturer as 50 km/h. In both cases steering was via the front wheels, with a minimum turning radius of 11.15 m (36.6 ft). Both drivers had a full set of standard steering controls, even with separate odometers. Each driver had a rectangular hatch in front of him, that could hinge upwards to provide an unimpeded view of the road; due to the short nose there were no dead angles in his field of vision. When closed the outside could still be seen via a vision slit, protected by armoured glass and fully closable through a small sliding armour plate. The environment could then be better observed by means of five prismatic blocks placed below the raised circular top hatch. The blocks could be quickly replaced when damaged. The front of the main compartment also had small side hatches, likewise fitted with vision slits; the back driver had such a small hatch available within the larger hatch at his right. In darkness vision could be improved by two large headlamps on both the front and the back of the vehicle.

The front wheel used helical springs and hydraulic dampers; the rear axle leaf springs. It was connected on both sides to the Trado-system by which all four rear wheels could be driven. Hydraulic brakes were present on all six wheels. It had been intended to fit bulletproof tyres, but as none were available conventional Dunlop Trackgrip terrain tyres were used. Bulletproof tyres would have slightly reduced the maximum speed. Special armoured hubcaps protected the hubs. As the sloped armour caused a considerable overhang at the nose of the vehicle it was equipped at this point with two rather large unpowered auxiliary wheels, to prevent ditching. If ditched or stuck in soft soil, freeing the cars could be facilitated by two detachable boards, attached on each side above the rear wheels, which position also reduced dust clouds while driving and covered what otherwise would have been a very conspicuous light-dark contrast between the angled upper hull and the large shadowed part below the rear fender. There were two fuel reservoirs, a main and a reserve tank, below the floor plate of the main compartment, holding a total of 85 litres of petrol; this allowed for a range of about 200-225 kilometres. The numbers given by some sources of a hundred litres and a range of three hundred kilometres, are incorrect.

DAF sprayed a red lead primer on the cars and then finished them with a semi-gloss coating in the standard colour of the Dutch Army: "army green", that was at the time conceived as a rather dark and dull bronze. The orange triangle Dutch national insignia were absent on the M 39s. Instead during the fighting as a makeshift solution on occasion the Dutch flag was used, sometimes as such, in at least one case painted as a large red-white-blue tricolour on the back of the vehicle. Black military vehicle registration numbers, from III-2201 to III-2212, were applied on a rectangular orange background. No large white identification numbers were used, as did the other Dutch armoured car types. As was usual for Dutch army matériel during most of the twentieth century, no camouflage pattern was applied. The inside was sprayed with an aluminium colour, with the exception of the inside of doors and hatches.