Germany’s Goliath Remote Controlled Mines

It’s not often that I will describe something that is designed to carry 100 kg of explosives and blow things up, but the Goliath tracked mine is an exception. It looks like a baby First World War tank, and can be controlled from up to 650 meters away – what isn’t to love?!

It seems those who encountered them during the war agree too, because there are dozens of photos of troops riding on them, playing with them, or simply staring at them with a puzzled look.

Background and Rationale

The concept of the Goliath tracked mine came from a rather basic need: to get explosives across a battlefield safely. In combat, explosives are not just weapons, they can also be used for obstacle clearance, such as demolishing buildings or blasting a hole through barbed wire.

These explosives are often carried by engineering teams, who have to expose themselves to great dangers to perform their mission. This need was made particularly evident during the First World War, with the massive use of fortifications, obstacles, barbed wire, minefields, etc.

Combat engineers and infantrymen faced severe risks from these defensive measures. This dangerous and labor-intensive process necessitated the development of a safer, more efficient means of delivering explosive charges.

A natural solution to this was removing the human element from the equation, and finding a way of delivering explosives precisely without endangering a combat engineer. Attempts at doing this just occurred as early as the First World War. France carried out significant work, as did the US, but the end of the war meant funding and interest in these tools waned.

First World War battlefields were extremely hazardous to cross.

The Germans recognized the potential of these systems to extend the reach and reduce the risk to their own troops and experimented with remote-controlled vehicles during the interwar period. The Soviets and Japanese also dabbled with this technology prior to the Second World War.

The impetus for developing such a vehicle was further driven by specific tactical requirements encountered by the Wehrmacht. German forces frequently encountered well-defended positions that were difficult to neutralize using conventional infantry assaults or artillery bombardments alone. The static nature of trench warfare, urban combat scenarios, and heavily fortified defensive lines highlighted the need for a tool that could penetrate these defenses with precision.

Enter the Goliath. The Goliath was envisioned as a solution that could breach wire obstacles, clear minefields, destroy bunkers, and even disable tanks without exposing German soldiers to the immediate dangers of the front lines.

A prototype for the Goliath.

Development of the Goliath

The project began around 1940 by the company Borgward, who made a number of remotely operated vehicles during the war. By this point, advances in radio technology made the design of such a vehicle more practical.

The initial prototypes of the Goliath culminated in the introduction of the Sd.Kfz. 302 model in 1942. This version of the Goliath featured an electric drive system powered by two rechargeable electric batteries.

This model, while quiet in operation and thus advantageous for stealthy approaches, was hampered by a limited operational range. The batteries allowed the Goliath to travel only about 1.5 kilometers (approximately 0.9 miles). Additionally, the need for frequent recharging of the batteries posed challenges in the field.

A Goliath being demonstrated to German officers.

Recognizing these limitations, German engineers developed an improved version that could overcome the range and endurance constraints of the electric model. This led to the creation of the Sd.Kfz. 303 model, which came with a gasoline engine.

This provided the Goliath with a significantly extended range of up to 12 kilometers (7.5 miles), making the vehicle much more versatile. It also enabled it to carry significantly more explosives.

The transition from an electric to a gasoline powerplant addressed the primary shortcomings of the initial design. The gasoline engines allowed the Goliath to cover greater distances and operate for longer periods, all the while carrying a bigger payload.

When looking at a Goliath today, it is hard to imagine that they were designed to be disposable from the outset. But carrying a man-sized quantity of explosives made its job rather unsurvivable.

The vehicle had enough explosives to level a building.

Design of the Goliath

The vehicle was 1.7 meters long, 900 mm wide, and 0.6 meters tall, making it small and low-profile enough to be difficult to spot on the battlefield. This compact size was crucial for the Goliath’s use, allowing it to navigate through narrow passages, trenches, and over rough terrain to reach its target.

The Goliath’s construction focused on durability and mobility. The vehicle contained three main compartments: a cable reel at the rear, a powerplant in the middle, and an explosive charge at the front. It rolled on caterpillar tracks driven by sprockets at the front. These provided the necessary traction and stability to traverse the varying terrains it would likely encounter along its journey, including mud, rubble, and uneven ground.

As mentioned, the tracks were driven by either an electric motor in the Sd.Kfz. 302 model or a gasoline engine in the Sd.Kfz. 303 models. The Sd.Kfz. 302 was powered by two Bosch 2.5 kw electric motors, and weighed 370 kg (815 lbs). This gave it a top speed of about 10 kph on solid ground. The batteries were stored in compartments along the hull sides.

A top-down view showing the internal components. of a Goliath.

The Sd.Kfz.303 came in two sub-variants: the Sd.Kfz. 303a and the Sd.Kfz. 303b. The Sd.Kfz. 303a featured a 12.5 hp, 703 cc Zündapp motorcycle engine, while the Sd.Kfz. 303b had a slightly larger 804cc engine. These types weighed 430 kg (950 lbs).

These powerplants enabled the Goliath to move towards its target with reasonable speed and agility, although it was still relatively slow compared to other military vehicles. They were slightly faster than the electric versions, with a top speed of 12 kph on solid ground. Interestingly, only the electric version was capable of reversing. If you wanted to reverse directions with the gasoline versions, you’d need to turn around!

The gasoline and electric versions can be easily identified by their top plates. The electric version has a flat top plate, while the gasoline versions have an air intake on top.

This Goliath at the Musée des Blindés in Saumur, France, is an Sd.Kfz. 303, indicated by the air intake on top.

One of the most critical aspects of the Goliath’s design was its payload capacity. The electric version could carry up to 60 kg (130 lbs) of explosives, while the Sd.Kfz. 303a could carry 75 kg (165 lbs), and the Sd.Kfz. 303b could carry 100 kg (220 lbs).

This payload was housed at the front of the vehicle. The substantial amount of explosives meant the Goliath was no joke – 100 kg of explosives are plenty for demolition tasks, destroying fortifications, clearing obstacles, and disabling tanks and other armored vehicles.

Of course, the explosives had to actually arrive at the target first, so the Goliath received some very light armor, consisting of thin steel plating ranging from 5 to 10 millimeters thick. This armor was intended to protect the vehicle’s internal components, including the explosive payload, control systems, and drive mechanisms, from small arms fire and shrapnel.

A top down view showing the internal components. of a Goliath.

However, it was not designed to withstand direct hits from heavier weapons, such as anti-tank guns or artillery shells. The light armor contributed to the Goliath’s overall lightweight design, facilitating easier transportation and deployment. Any thicker and it would have been very difficult to move and required more power.

All versions of the Goliath were controlled remotely via a long, spooled cable that connected the vehicle to the operator’s control unit. This cable transmitted electrical signals that allowed the operator to steer the vehicle and control its movements. The reel of cable was stored in a compartment at the rear of the vehicle.

Remote Control System

The remote control mechanism of the Goliath enabled operators to maneuver the Goliath towards its target and detonate its explosive payload from a safe distance, significantly reducing the risk to personnel. The design and functionality of this remote control mechanism were central to the Goliath’s success (or failure).

At the heart of the Goliath’s remote control system was the control box, operated by a soldier from a protected position. This control unit was connected to the Goliath via a long cable, typically several hundred meters in length, with some models featuring cables up to 650 meters long.

The cable comprised three strands: one for detonating the explosives, and two for controlling the vehicle’s movements. Its length allowed operators to remain at a safe distance from the vehicle, minimizing their exposure to enemy fire and the explosion resulting from the detonation of the Goliath’s payload.

The strands connected to a corresponding switch on the controller.

The cable transmitted electrical signals from the control unit to the Goliath’s motors and steering mechanisms. These signals enabled the operator to direct the vehicle’s movements with a high degree of precision. The control box featured three switches which the operator used to send commands to the Goliath. By manipulating these controls, the operator could move the Goliath forward, backward, and execute turns, guiding it through obstacles and towards its designated target.

The Goliath’s internal control mechanisms converted the electrical signals received via the cable into mechanical actions. These actions were carried out by the vehicle’s drive system, which adjusted the speed and direction of the tracks by increasing or decreasing the voltage sent to the motors. Each switch on the controller had three positions for different voltage amounts.

In addition to steering the vehicle, the cable also included a detonator wire. Once the Goliath reached its target, the operator could trigger the explosive payload remotely by turning a key on his controller. This sent a detonation signal through the cable. This capability allowed the operator to control the exact timing of the explosion, ensuring that the Goliath was in the optimal position to achieve maximum destructive effect against the target, whether it be a fortification, a minefield, or an enemy vehicle.

US troops inspecting Goliaths. They were known as “Beetles” and “Doodlebugs”.

Despite the useful nature of the remote control mechanism, it also introduced certain vulnerabilities. The reliance on a physical cable for signal transmission meant that the Goliath was susceptible to being rendered inoperative if the cable was severed or damaged. This could happen due to enemy fire, sharp terrain features, or obstacles on the battlefield. If the cable was cut, the operator would lose control of the vehicle, potentially leaving it stranded and unable to complete its mission.

The cable, being a physical connection, also limited the vehicle’s operational range to the length of the cable itself, restricting its deployment to scenarios where the target was within this range. Understandably for the period, the Goliath lacked an onboard vision system, so the operator had to rely on a line of sight to guide the vehicle to its target. Across a shell-torn, rubble-filled battlefield, it was probably quite easy to lose track of your robot.

They make for fun toys, however!

Operational Use

The Goliath was employed in several key combat environments, including urban warfare, beach landings, and assaults on heavily fortified positions. One of the most notable uses of the Goliath was during the Normandy invasion in 1944, with a number of photos and videos showing US servicemen playing with the little robots on the beaches after they had been captured.

In urban settings, such as during the Warsaw Uprising in 1944, the Goliath was used to target and demolish barricades erected by resistance fighters. The vehicle’s small size and tracked mobility allowed it to navigate through the narrow streets and debris-filled environments of a city under siege. By remotely guiding the Goliath to resistance strongholds, German forces could deliver explosives with precision.

Goliaths were also used for mine-clearing operations during the Battle of Kursk, in which German armored units had to battle through multi-layered Soviet defenses that were saturated with mines.

US Navy personnel inspect captured Goliaths on Utah Beach after the invasion.

However as mentioned, the Goliath faced several significant challenges that limited its overall effectiveness, like its reliance on a control cable. While this cable allowed for precise remote control, it was also a critical vulnerability. The cable could be easily severed on the battlefield. Once cut, the Goliath would become inoperative, stranded on the battlefield and unable to complete its mission. This vulnerability was particularly problematic in intense combat situations where the likelihood of the cable being damaged was high.

A severed cable also meant there was 100 kg of high explosives sitting somewhere on the battlefield – which isn’t very convenient for anyone.

The Goliath’s relatively slow speed was an issue too. While its tracked design enabled it to traverse various terrains, its maximum speed was insufficient to evade enemy fire effectively. This made the Goliath an easy target for enemy soldiers who could disable it before it reached its intended target. The slow speed also limited its ability to react quickly to dynamic battlefield conditions.

Many Goliaths were simply never used. Here is a huge pile of captured vehicles.

Another set of challenges pertained to the logistical and mechanical aspects of deploying the Goliath. The initial Sd.Kfz. 302 model, powered by electric batteries, had a limited operational range of about 1.5 kilometers, restricting its use to relatively close targets. The batteries required frequent recharging, which posed difficulties in maintaining multiple units in combat-ready condition. Although the later Sd.Kfz. 303 models with gasoline engines offered an improved range of up to 12 kilometers, they required additional maintenance and had to sip from Germany’s already constrained fuel supplies.

Mechanical reliability was another concern. The complexity of the remote control and propulsion systems meant that the Goliath required careful handling and regular maintenance to function properly. Any malfunction in the control system, drive mechanism, or explosive payload delivery could render the vehicle ineffective, potentially wasting valuable resources.

Due to these operational challenges, the Goliath was not deployed as widely as initially envisioned, despite thousands being built. Its use was often limited to specific, high-risk scenarios where its remote-controlled capabilities could be most effectively utilized.