Jank One Man Tank

Federal Republic of Germany (1970)
Light Tank – None Built

There are some ideas which are so bad they just keep being invented because their absence seems to give someone licence to believe they are needed. Whether it is mine proof boots or a helmet mounted gun, some ideas keep coming back around again and again. One such a mistaken concept is that of the one-man tank. Right from the first days of the tank in World War 1, there were ideas for cramming one man inside a vehicle, usually lying down, and tasking him with all of the roles of command, coordination, and combat.

Whilst we may forgive WW1 era ideas as being part of that early evolutionary process where some terrible ideas came and went and were left behind, they are less forgivable in WW2. By 1970, a time when the armies of NATO were facing off across Western Europe with the huge tank forces of the Soviet Union and Warsaw Pact, when Johann Jank submitted his idea for a patent, the whole concept should have been obviously ridiculous, impractical, and pointless.

The Man

Little can be found on Johann Jank. From a variety of patents, we can get an insight into the man though. It is known from his filings between 1962 and 1970 that he lived in 8783 Hammelburg (Hammelburg Administrative District) and that he was the manager of the Johann Jank Company, Karosseriebau-Wagenau, Sägewerk, Hammelburg – a town in Bavaria. ‘Sägewek’ means ‘Sawmill’ and this likely explains 6 or the 7 patents in his name, as these are all related to saws of different types. To this day, the timber industry is still a presence in the area.

The Area

Not only is the Hammelburg area known for the timber industry, it was also home to an army training camp well into modern times and during the Second World War, home to a prisoner of war camp: Oflag-XIII. The camp is otherwise famous as the scene of the failed attempt by General Patton to rescue his son-in-law who was interned there as a POW, an attempt which lost 5 tanks and 32 men, with about 250 wounded in the ‘Hammelburg Raid’ by Task Force Baum.

Whether Jank was in the area at the time or what he did during the war is not yet known but, by 1962, he was living in this area and could not have avoided some knowledge of its war time fame. Perhaps it was this which sparked the idea of a one-man tank or maybe it was purely a vivid dream he put on paper, but whatever spurred it, this design, filed during the Cold War, would have been as hopeless in 1970 as it would have been in 1945.

The Design

Jank’s goal was to build a one-man tank, running on tracks, which was well-armed and highly maneuverable. Jank had done some research on the subject as, in his application for a patent filed on 5th May 1970, he wrote that a common failing of such one-man tanks was the location of the engine behind the operator, creating a relatively long vehicle due to the engine’s length being in addition to the length of the operator who would be lying prone inside. No engine type, size, or transmission were discussed at all, perhaps leaving the decision to any user who might be willing to purchase the rights to his idea. To this end, Jank envisaged the power plant being on the side of the vehicle, alongside the driver, under armor and creating a rather ‘fat’ looking machine, but one which was only marginally longer than the operator. This would have the advantage not only of a shorter vehicle but also meant it was easier for the operator to enter and leave from the rear via a pair of doors slightly recessed into the rear armor to provide some additional protection from enemy fire.

The overall shape of the vehicle was heavily curved, very low to the ground, and distinguished by the cannon projecting from the front, slightly off-center to the right. With the armament located in the front right of the machine and the engine behind that, it left the full left-hand side width of the vehicle for the operator.

Steering and propulsion would be controlled by the operator with his feet working pedals behind him and a pair of handles in the front, almost like the handlebars on a bicycle, for steering and firing the weapons. A set of gauges to his right would tell the operator the vehicle’s speed, etcetera. The tracks were surprisingly robust and together amounted for nearly a third of the width of the tank. The track was supported at both ends by large wheels, although the design does not make clear which (or both) of the sprockets would deliver drive. Four small road wheels held the vehicle on the ground and each appears to be on a small swing arm, suggesting either torsion bars under the operator or even that a torsilastic-type suspension was considered. Finally, two small return rollers would support the track around its run.

Visibility for the operator was poor, as he would have to lay down in the prone position the whole time with no option to sit up. He would therefore only be able to look ahead though two small view ports in the front armor and no periscope is drawn or discussed. Visibility, therefore, would have been limited to just the front, although two small headlamps are shown to help illuminate the way. Alongside these two ports is a third one containing the aimining devices for the weapons. Arranged in this way would be sure to render the vehicle unable to fire on the move, indicating perhaps Jank was thinking of this purely as some kind of low-profile weapon of ambush. One small note on the design is the small ‘pimple’ on the top for which there is no stated purpose. It is far too small to be a hatch and in the wrong place to get out of anyway. It is not marked by Jank as a feature worth discussing so it can only be assumed to be either some kind of vent, either for air for the operator or perhaps for an exhaust. No additional vents or air-supply for the engine or for cooling are shown or discussed.

The final point Jank makes on mobility is that the vehicle would be amphibious and able to be driven through water by means of a propeller, presumably from a power take-off (PTO) from the engine, although neither the propeller nor PTO are shown. From a point of view of safety, the metacentric height for this vehicle would likely be such that the rear was lower in the water. This would be due to the weight of the engine raising up the nose so that the viewports were above the water level although, with no other form of propulsion, the vehicle would be hard to navigate on even a slightly rippled surface. Far worse would be that the only egress, the rear doors, would actually be underwater at the back and have to be exited backward. There is simply no way a crippled vehicle of this type could be exited in open water, as the operator would not be able to kick open the back door against the force of water outside so would have to let the vehicle fill up with water before he tried to exit backward. By the time this happened, the vehicle would be gracing the lake bed as a coffin for the hapless and unfortunate operator.

Armor

No details of the armor are provided but, from the shape, it could be inferred that Jank was picturing a heavy construction, more than simply bulletproof and formed in a large casting with an extensively curved body including the sponsons over the tracks at the side and at the rear.

Armament

Two armaments are shown in the drawing and are described with this filing as “fully automatic, rapid-fire firearms” although no details are given. From the obvious size differences between the two guns drawn in the application, the larger of the two could be taken as a small anti-tank gun with the smaller gun, located coaxially, as a machine gun.

Conclusion

Jank’s design is very poor. There is simply no getting around the fact that a lone operator is overworked, having to manage communications with other troops, a weapons system, and the control of the vehicle at the same time. These were obvious flaws in WW1 and, in 1970, there was little excuse to not appreciate this, especially as he had already looked into some design background. The inability of the operator to be in any position other than prone would lead to fatigue, the impossibility of not drowning if the machine broke down in open water and had to be abandoned and the poor visibility made this a very poor design for fightability and survivability. The saving grace for Jank is the layout. He had clearly given some serious thought to the problems of a one-man tank and his design is a competent one at that, putting the engine and armament offset to create a more compact vehicle. The problem is that it is a competent design of an inherently flawed concept and that no matter how good he made it, it would never be a replacement for a multi-person crewed larger vehicle. No examples are ever known to have been built and Jank did not apply for more military-related patents. Presumably, he went back to what he knew and stuck with that instead.

Jank one-man tank specifications
Engine	Not specified
Speed	Unknown
Suspension	est. torsion bar or torsilastic
Armament	est. fully automatic cannon and machine gun
Armor	~bulletproof

Sources

DE1453031(a1) Adjustable Gang Saw, filed 17th April 1964, granted 12th December 1968
DE1877705 (U) Zerlegbare Campinghuette, granted 14th August 1963,
DE1849464(U) Schaltafel, filed 2nd February 1962, granted 5th April 1962
DE2342441(A1) Saw blade group adjustment on a saw, filed 22nd august 1973, granted 14th March 1974
DE1803267(A1) Gang saw, filed 16th October 1968, 14th May 1970
DE1503957. Adjustable Gang Saws, filed 28th January 1965, granted 28th August 1969