Last week marked the 74th anniversary of Operation Overlord. Also known as D-Day, Codenamed Operation Overlord saw 156,000 American, British, and Canadian forces land on the northern beaches of France. The invasion, which began on June 6, 1944 and lasted until late August, saw the liberation of Northern France. The landing at Normandy has come to mark the “beginning of the end” of the war in Europe. Many facts about the fateful day are widely known. The Higgins landing craft has become synonymous with the invasion as the boat that won the war. But first-hand reports from the day recount so many different boats waiting to take the beaches. However, one type of vessel that is often forgotten from the narrative is the British midget submarines that played a key role in the landing efforts.
Preparation for D-day had been extensive. Operation Neptune, the codename for cross-channel portion of the invasion, was pushed back 24 hours due to bad weather. But by June 6th, paratroopers and glider troopers were already in position behind enemy lines. U.S. Forces would go in at Utah and Omaha Beach. The British and Canadian forces were to capture Gold, Juno and Sword beaches. Under Neptune was Operation Gambit, the use of two X -class British submarines that would mark the ends of the British and Canadian invasion beaches. The X-craft submarines were built at a secret submarine training base at Lock Erisort on the Isle of Lewis in Scotland. By 1943, the Royal Navy had developed a 52-foot midget submarine they called X-craft. The submarine could carry a four-man crew and remain at sea for days. She could dive up to 300 feet. Due to her small size, the X-craft had only one access hatch and a small periscope that was mostly unreliable. Navigation was done through a Browns A Gyro Compass and Auto Helmsman. The X-craft could either be towed by a conventional submarine or launched from the deck of a submarine to reach its intended target. Two 3,570-lb mines were attached to its sides. A hand crank could release them when they were positioned below the hull of an enemy ship. The small crew consisted of one commanding officer, a first lieutenant, an engineer, and a diver.
In the months leading up to Operation Overlord, it was up to the x-20 to gain as much recognizance as possible to prepare for the mission. During the day the submarine would monitor the beaches using its periscope and at night divers would swim to shore. Echo sounding measurements were taken to find distance and landing positions. Over two nights, the divers surveyed the beaches at Vierville, Moulins, St. Laurent and Colleville- the beaches that made up “Omaha” beach. Plans were to have the divers make a third trip. However, bad weather and lack of food forced the commander to return to the HMS Dolphin where she would be towed to Scotland. Two X-class submarines would return to the beaches of Normandy leading up to the invasion to help aid in what would become the eventual downfall of the German troops. HMS X-23 and HMS X-20 would be the first vessels off the shores of Normandy leading up to the attack. Arriving on June 4, the X-crafts fixed their positions and waited for nightfall to surface to begin their mission. It wasn’t until they surfaced that they received the message that the operation had been postponed due to bad weather. According to the Royal Navy Submarine Museum, “On 6 June at 0445 the submarines surfaced in rough seas. They set up the 18 feet high navigation beacons that each were carrying and switched them on. These shone a green light indicating their position away from the coast, visible up to 5 miles away although undetectable to anyone on land. They used the radio beacon and echo sounder to tap out a message for the minelayers approaching Sword and Juno beaches. The incoming fleet appeared on time and roared past them.” Sailing out of Hayling Island in Hampshire, the two submarines were nervous hearing that the mission had been delayed. The conditions inside were cramped and there was not even enough room to stand. There was fear that their oxygen levels wouldn’t last them another day. The men survived on rations of tea and baked beans as they waited for word. The crew would sleep in four-hour rotations in the battery compartment. Each evening they would surface to receive the secret code worded message on the BBC broadcast that would tell them when it was time. At the darkest of night, they would surface so the men could walk on the deck to get some air. Leading up to June 6th, the crews watched the German troops play football on the shore through the periscope. And then the message came to be ready to surface at 4am on June 6th.
Operation Gambit was a success, the British and Canadian forces were able to land on their respective shores without falling off course or hitting any rocks, thanks to the beacons from the X-crafts. In 2011, the small crews of X-23 and X-20 were honored with a granite memorial donated by Prince Charles on Hayling Island, Hampshire. Today, only one X-craft vessel remains- the X-24 which can be seen at the Royal Navy Submarine Museum. While the X-20 and X-23, served only a minor role in the D-Day invasion, it shows the vital role a submarine can play in a nation’s arsenal.