7 Clever Inventions That Defined D-Day

6. Tide-prediction machine

North West Europe was a new environment for most of the Allied troops. Invading it required a broad evaluation of all the factors that would affect the effectiveness of the operation. They would use the sea for the landings, so the tide was a major factor. Some troops would land from the air, which would be impacted by the sky conditions. Landing at night would use the moon for light. The actual battle on D-Day would need a conducive weather.

Planners of the June 1944 invasion took all these factors into consideration. One of the solutions hatched out of this rigorous process was the tide-prediction machine. The naval operations needed calm waters. Their ground troops also needed to land at low tide to escape the German beach obstacles. To achieve the best combination of these factors on the D-Day, the planners had to consult widely to get the required best combination of all these factors. They consulted some meteorologists and other experts in the process. Eventually with the help of a British mathematician Arthur Thomas Doodson, the Allies managed to reveal tidal patterns using a specially modified machine. That is how they arrived at the 5th to 7th June window as the exact timeline for the operation.

5. Pluto

PLUTO stands for “Pipeline under the Ocean”. The Allied troops needed sufficient fuel to operate all their equipment. As a solution to this, they made a network of flexible underwater pipes running from the Isle of Wight to Port-en-Bessin, the connection point between the Gold beaches and Omaha.

The pipes drew petrol from Britain and supplied it to the Allies in Europe, giving them access to enough fuel for their naval craft, aircraft, and terrestrial vehicles. There were initially two PLUTO pipelines and another one was added afterward. This ran from Dungeness, Kent coast to Boulogne France. More of these pipes were added as the Allies advanced further across the region. Each underwater pipeline measured 3 inches wide and was attached to huge floating spools referred to as ‘conundrums’.

4. Horsa Gliders

Built by Airspeed Limited, Horsa gliders were central to the Allied airborne assaults in World War II. They were used significantly throughout the latter stage of the war. On D-Day in particular, the Allies used these gliders on an exceptional scale to carry soldiers and supplies to Normandy. Before gliding into the landing zone, these gliders would be towed by bomber or transport aircraft. Gliders were particularly helpful in transporting equipment that could not be dropped by parachutes due to heavier weight, or in places where it was impossible to use bigger transport aircraft. They allowed for easier unloading of cargo given their removable tail and hinged nose. But gliders had a downside, though, their structure was flimsy and would often break apart on landing, not to mention that they were also difficult to operate.

3. Hobart’s Funnies

These were special World War II tanks uniquely modified to carry out tasks that the most standard tanks had difficulty handling. The specially modified Hobart’s Funnies were operated by the 79th Armored Division of the United Kingdom or by experts from the Royal Engineers. The unusual vehicles played a central role throughout the Battle of Normandy and most importantly on D-Day.

The troops needed sufficient armored support to be able to break through Germany’s coastal defenses at Normandy and the rest of Western Europe. They had this lesson from the August 1942 failed raid at Dieppe, which also exposed how challenging it was to land armored vehicles in the course of an amphibious offensive.

The Allies, therefore, designed the reinforced vehicles to perform specialist tasks as well as reinforce their troops on the ground on D-Day. The vehicles were named ‘Hobart’s Funnies’ after their architect, the Major-General Sir Percy Hobart. Hobart’s Funnies included the Crocodile flamethrower tank, the Duplex Drive (DD) swimming tank and the Crab mine-clearing flail tank.

2. Mulberry Harbors

Mulberry harbors were temporary moveable harbors developed by Britain during World War II with the aim of facilitating the rapid offloading of consignment onto beaches during the Allied Normandy landings of June 1944. Their use was not limited to D-Day. The Allies needed to build up their backups and supplies constantly in Normandy to sustain the momentum of the incursion. They had learned earlier on that they needed to secure ports and harbors to provide a platform for men and cargo and protection against inclement weather and rough waters respectively. On that ground, the Allied groups came up with two artificial harbors dubbed ‘Mulberries’. These were made by sinking dated ships and large concrete structures.

1. German Defenses

The highly decorated Field Marshal Erwin Rommel believed that the Allied Normandy landings would take place at high tide. This would be a time when the beachhead would be at its narrowest. So he devised a series of obstacles to be disguised under water. The obstacles were comprised of jagged-edge iron ‘hedgehogs’, explosives and round, flat landmines attached to wooden posts. The iron hogs would tear the bottom of a vessel exposing the Allied troops to German fire during high tide. The explosives and the landmines would explode on impact with the landing craft. Inland, the Field Marshal, also designed a system of large posts vertically fixed into the ground to prevent gliders from landing in open areas. Being Rommel’s idea, these obstacles were codenamed ‘Rommel’s Asparagus’. These turned out to be of less value to the Germans as the Normandy landings occurred at low tide when all the obstacles at the beach were clearly exposed.