5 tanks that changed the course of the First World War

The British Mark I came in two different varieties. The ‘male’ tank was armed with two 6-pounder guns, which were mounted in armoured sponsons [gun platforms] attached to each side of the tank. Each sponson was also fitted with an additional machine gun and a third machine gun was mounted in the driver’s cabin firing forward. The 6-pounder gun was designed to destroy fortified machine gun posts. It was not as good at killing a lot of enemy infantry unlike the female tank. The ‘female’ tank was armed with two machine guns in each sponson and one fitted in the driver’s cabin, making it more useful on the battlefield.

Following the first use of tanks on the battlefield at the battle of Flers-Courcelette in September 1916, the German forces turned their attention on how to defeat them. One new anti-tank measure they introduced was to widen their front-line trenches to prevent the British tanks driving straight across the top of them.

This new defence tactic was discovered by the close analysis of aerial photographs taken by the Royal Flying Corps. A solution was looked for and found in the history books: a ‘fascine’ was a large bundle of branches bound together and used to cross castle moats in medieval times. Fascines were used as a counter measure in First World War. The branches were bound together tightly with chains and strapped to the ‘unditching rails’ on top of the Mark IV tanks.

Three tanks would approach a German trench. The first tank would stop at the edge of the trench and drop its fascine. It would then move left and continue to machine gun the enemy troops in the trench. The second tank would do the same but move right along the edge of the trench. The third tank would drop its fascine into the trench and then continue forward driving over the top of the densely packed bundles of branches to the other side of the enemy trench.

There are a number of First World War British Regimental battle diary entries that report tanks having to return back to the start line because they were low on fuel or had run out of machine gun ammunition. This left the infantry in the front line vulnerable.

It was impractical for an unarmoured, wheeled supply lorry to follow the tanks across no man’s land. The army needed a method of resupplying the tanks on the battlefield and the simplest option was to build new supply tanks or convert old tanks. Their armoured hulls would protect the crew and the stores and, as they were a tracked vehicle, they could cross the same terrain as the battle tanks.

To enable even more stores to be transported to the front, a large metal-and-wood sledge was built. It did not use wheels but had large skids, that looked like giant skis, fixed to its bottom. The sledge was then attached to the back of the supply tanks by chains or strong rope and dragged over the bumpy terrain. In the side sponsons, the holes where the guns would have been mounted were blanked off with metal plates. The use of supply tanks changed the course of the First World War by allowing more gun tanks to remain on the battlefield.

In the middle of the First World War, French industry was finding it difficult to produce their large, heavy tanks with powerful engines, such as the Schneider CA and the Saint Chamond, in the numbers required.

One Colonel Jean-Baptiste Estienne started looking for a solution. He came up with the idea of using a two-man, small, light tank that was cheap to build and armed only with a machine gun, that could be built within the manufacturing restrictions of wartime French industrial capabilities. When Renault began mass-production of its FT light tank, Estienne would be a key advocate. It was the first tank with a turret that traversed 360 degrees in order to see action on the battlefield. The similarities in design can be seen today in modern tanks. Some saw active service in the Second World War.

Five Renault FT tanks could be built for the same cost as one Saint Chamond heavy tank and Colonel Estienne believed in the battlefield tactic of a 'bee swarm' of light tanks: the strategy that fast, multiple targets would be harder for the enemy to deal with than one large, slow-moving tank.

This revolutionised the way battles were fought. Large-scale artillery bombardment no longer preceded an attack, which was usually necessary to minimise the amount of shell holes the tanks would have to negotiate. The tank 'bee swarms' were able to neutralise enemy machine gun posts, allowing the infantry to advance and attack in strength.

The Germans only built 20 of the Sturmpanzerwagen heavy tanks, one of their own tank projects, which were based on the A7V tracked chassis. They did not change the course of the war as there was only a few of them.

However, after the battle of Cambrai in November and December 1917, the Germans actively looked for knocked-out British Mark IV tanks that could be towed off the battlefield. They recovered around 300 damaged tanks and repaired 170 back to fighting condition. The tanks’ machine guns and the 6-pounder guns were replaced with German army weapons.

In the spring of 1918, after they had been painted with German crosses they were sent into battle to fight against the forces which had previous owned them. This came as a shock: all British tanks now had to be painted with large white-red-white stripes on their side and roof, so they could be distinguished from German-operated Mark IV tanks from the air as well as on the ground.

This also meant that British Mark V ‘female’ tanks, armed only with machine guns, were now vulnerable, they could not knock out an enemy tank. A stopgap solution was to add a ‘male’ sponson, armed with a 6-pounder gun, to one side of a ‘female’ tank. This modified tank was given the name Mark V 'composite tank', also known as the 'hermaphrodite' tank.

Craig Moore is the author of Tank Hunter: World War One, a guide to the development and deployment of tanks in the First World War (The History Press, November 2017)