Naval Combat Demolitions Units
The history of the US Navy SEALs dates back to World War II and the various special operations units that were created to fill specific needs. Amphibious landings were still a new operation and new tactics were written with every operation. New vehicles were developed to get soldiers to shore quickly and efficiently, but there were still obstacles that could cause failure of a landing. Defenders could fortify a beach with obstacles which could tear out the hull of an approaching boat and sink it, drowning it's men and blocking the approach for other boats. Underwater obstacles could also be natural, such as coral or sandbars, completely uncharted, and change daily. To ensure the successfulness of landing operations the armed forces, and the US Navy in particular, began creating new units that could handle specific dangerous tasks that no one else could complete.
A few Naval officers had recognized the need for permanent specialized units that would clear beaches for landings, but initially reception to this idea was cool. Lieutenant Commander Draper Kauffman had been ordered to form a secret unit whose job was to clear beaches of obstacles. Created in May of 1943, the unit's mission was to clear beaches of obstacles. There was a lot of initial wrangling with the US Army over who had what responsibility. Initially it was decided that the Navy had responsibility for clearling obstacles to the waterline and the Army everything above the water, but this caused confusion; with a rising and falling tide who was to say what the waterline really was? Eventually it was decided that some overlap was fine but that the Navy's primary responsibility was from the high-tide mark down. Initial work blowing obstacles under water was not encouraging so the early training focused on operating from boats that would deliver the demolitioneers to the beach.
The most well known of the WWII Naval special operations units were the UDT's or Underwater Demolitions Units, but the first operational Naval demolitioneers was NDU 1 ( Naval Demolitions Unit ). NDU 1 was very much an ad-hoc unit; the men who staffed it had been experienced blasters in civilian life but were all very new to the US Navy. Thrown together with little training, they were immediately sent to Africa to take part in Operation Husky, the Invasion of Sicily. Despite the urgency of their formation and deployment there was not much for them to do and they did not take part in any of the landings. Afterwards they were sent back to the states, where many of them were sent to a new school in Fort Pierce, Florida, and placed under the command of Lieutenant Commander Kauffman, who was forming the Navy's first combat demolitions units. Kauffman was uniquely qualified for the position; before the war had started he had been a volunteer ambulance driver in combat conditions and then a mine disposal volunteer with the British Royal Navy before being tapped to create the US Navy's Bomb disposal school.
Kauffman's school began training what were called NCDU or Naval Combat Demolitions Units. Because they were to operate from boats and not as swimmers the term frogman was not used until later in the war. The early Combat Demolitions units called themselves "Demolitioneers" due to the primary focus on demolishing obstacles and were often known as "Demos" to sailors in the fleet. Before the NCDU's could operate, however, they needed to be formed and trained. The US had never had a unit like this before, and Kauffman had to start from the ground up. The first Teams' members were recruited from the US Navy "SeaBee" Construction Battalions and Army/Navy Scout & Raider groups. Training was done originally at "Area E" located at Camp Perry in Williamsburg, Virginia in but quikly outgrew it. Fort Pierce in Florida was selected for a number of reasons including relatively warm water, privacy, and it's presence as an amphibious base where they had ready access to boats, demolitions, and Seabee naval engineers who would make the obstacles that they would learn to demolish. Training was also near a unit of Scouts and Raiders who could teach them some of their combat skills; in fact, the first NCDU classes were trained by Army Scout & Raider Sergeants who had completed the British Commando course. Camp Perry was only used by Kauffman's group for a short while; only six classes had been run there by the time it was shut down in the spring of 1944.
Kauffman had been given an important mission and not a lot of time to complete it. Seeking to train his soldiers in the skills and toughness that would be required for the rough duty of disarming mines or clearing beaches, Kauffman had his demolitioneers, as they were calling themselves, put through a intense training regiment. Seeking to quickly cut out those not qualified to serve in this new unit, a particularly grueling first week regiment was developed to test not only physical ability, but mental toughness and motivation. Thus began Hell Week and its traditional ending with "So Solly Day." As with later classes and current BUD/S classes, a large portion of those who started did not finish; 40 percent of the initial class ( of 35 enlisted and 5 commissioned ) had either quit or was in the hospital by the end of the first week. After Hell Week, potential frogmen had four more weeks of training; three weeks of demolition training and the fifth and last week called "Payoff Week" where all their skills were put together and they proved what they had learned.
Today's training at BUD/S mirrors much of what was developed and used then; loads of stress, PT, and teamwork in all weather and conditions. The goal, then and now, was to create teams of highly able and motivated men who would complete the mission regardless of the effort required. The original concept varied much from today's however. The first classes through the NCDU program wore heavy clothing, helmets, and life jackets and were not trained to get out of their boats; in fact they were tethered to them in case they fell out in heavy surf.
Following graduation, NCDU members were formed into six-man ( one officer and 5 enlisted ) units and sent to either Europe or to the Pacific theatre. The first class graduated was sent to Europe to participate in the 1943 landing at Sicily. They were not needed for the initial landings and spent their time salvaging wrecked landing craft and marking lanes through the sandbars for landing craft. The next seven NCDU's were sent to the Pacific theatre, some serving the next couple of years as NCDU's and others being folded into the new UDT program. NCDU 2, for example, served the Seventh Fleet from September 1943 until August 1945 without relief or rotation to the States for rest.
The NCDU's first blood came at Omaha and Utah beach during Operation Overlord. The NCDU's had been in England practicing for the invasions and developing procedures. One of the biggest problems they faced was a german obstacle called the belgian gate. The belgian gate was three tons of half-inch thick angle iron welded and bolted together into a ten foot wide by ten foot high barricade that would tear the bottom out of landing craft at high tide and block them at low tide. The NCDU's had to develop a fast way to take these gates down in such a way that they didn't send shrapnel from the explosions whizzing around on a beach full of soldiers and demolitioneers.
The solution was created by a member of a NCDU, Lieutenant Carl Hagensen. The Hagensen Sack was a waterproof canvas sack filled with plastique explosives with a length of primacord sticking out. There was a cord on one end of the sack and a hook on the other so that it could be quickly affixed to an obstacle and hooked into other charges for a simultaneous explosion. Sixteen hagensen sacks were required to bring down a Belgian Gate. Ultimately, over 10,000 of these sacks were sewn up and filled in time for the invasion, and each NCDU member carried fifty pounds of explosives into battle.
Another problem was that of manpower. Both the Army and Navy had underestimated the number of beach obstacles that would need to be cleared until just before the invasion. There were not enough NCDU or Army Engineer members to clear all the obstacles that would block allied forces from taking the beaches and pouring soldiers and supplies into France. The Army and Navy joined forces and created Gap Assault Teams, or GATs, to take down the beach obstacles. Each Team was made up of five NCDU members, five Army engineers, and three Navy Enlisted seamen who hadn't gone through NCDU training but were to help with the boats and explosives.
Originally the NCDU were to arrive just behind a wave of Army tanks and infantry who were tasked with clearing the beach of snipers. What actually happened in many cases was that the infantry waves arrived late or at the wrong area of the beaches and the combined Gap Assault Teams were the first to fight. Although they completed their missions successfully, operations did not go well for them. All told, nearly 50% of the NCDU teams members operating at Omaha beach would be casualties. The landings at Utah were much better with only a few NCDU casualties.
Despite being told that they would be the only thing alive on the beaches, the German defenders put up a spirited defense. Allied bombers had dropped their bombs too far inland, fearing friendly casualties, and the battleship bombardments of the fortified positions had not had a chance to completely destroy the armored concrete pillboxes and machine gun nests.
In addition to the fire from German outposts and fortifications, the GAT members had to deal with infantry men taking cover behind the obstacles they were trying to blow and tanks severing primacord lines strung between obstacles with their treads. There were so many American casualties on the beach that the water was red, and one surviving NCDU member stated that "If you fell down you came up with blood on your face." The Gap Assault Teams were no exception, and in many cases took the heaviest casualties due to being first on the beach. Several Landing craft were hit with German 88mm shells before they dropped their ramps and most of the teams came under heavy machine gun and sniper fire. Of the 16 gaps that were planned to be blown in the defenses of Omaha Beach on June 6th only five were successfully created that morning.
But they had performed a crucial task under extremely adverse conditions. What breaches they had managed to make allowed the landing craft to beach and disgorge tanks, troops, and supplies, and steadily the beach was taken and the German forces pushed back beyond the edges of the cliffs so that there was less enemy fire. After regrouping, the Teams went back at the next low tide later that evening and created another eight gaps, bringing the total to 13 and helping the heavier craft to disgorge their cargos. One group of NCDU's on Utah beach managed to capture 15 German soldiers who were hiding in a bunker that had been bypassed and were radioing targeting information. Using captured German explosives, they blew down the bunker door and then talked the Germans out.
NCDU's operated on Utah Beach until June 13th and Omaha on June 27th, 1944. Although they had taken many casualties, the NCDU's work at Normandy was considered a success and efforts began for the expansion of the Underwater Demolitions Team program. With the main landing in the European theatre done, the surviving NCDU personnel were moved to the Pacific theatre and consolidated into what was known as UDT Able.