Underwater Demolition Team

The United States Navy studied the problems encountered by the disastrous Allied amphibious landings during the Gallipoli Campaign of World War I. This contributed to the development and experimentation of new landing techniques in the mid-1930s. In August 1941, landing trials were performed and one hazardous operation led to Army Second Lieutenant Lloyd E. Peddicord being assigned the task of analyzing the need for a human intelligence (HUMINT) capability. at Waipio Amphibious Operating Base on Oahu to form the nucleus of a reconnaissance and demolition training program. It is here that the UDTs of the Pacific were born. Later in war, the Army Engineers passed down demolition jobs to the U.S. Navy. It then became the Navy's responsibility to clear any obstacles and defenses in the near shore area. A memorial to the founding of the UDT has been built at Bellows Air Force Station near the original Amphibious Training Base (ATB) in Oahu. ==Naval Combat Demolition Units==

In early May 1943, a two-phase "Naval Demolition Project" was ordered by the chief of naval operations (CNO) "to meet a present and urgent requirement". The first phase began at Amphibious Training Base (ATB) Solomons, Maryland, with the establishment of Operational Naval Demolition Unit No. 1. Six officers and eighteen enlisted men reported from the Seabees dynamiting and demolition school at Camp Peary for a four-week course. Those Seabees were immediately sent to participate in the invasion of Sicily, where they were divided in three groups that landed on the beaches near Licata, Gela and Scoglitti. Also in May, the Navy created Naval Combat Demolition Units (NCDUs) tasked with eliminating beach obstructions in advance of amphibious assaults, going ashore in an LCRS inflatable boat. Each NCDU consisted of five enlisted men led by a single, junior (CEC) officer. In early May, Chief of Naval Operations Admiral Ernest J. King picked Lieutenant Commander Draper L. Kauffman to lead the training. The first six classes graduated from "Area E" at the Seabee's Camp Peary between May and mid-July. Training was moved to Fort Pierce, Florida, where the first class began mid-July 1943. Despite the move and having the Scouts Raiders base close by, Camp Peary was Kauffman's primary source of recruits. "He would go up to Camp Peary's Dynamite School and assemble the Seabees in the auditorium saying: I need volunteers for hazardous, prolonged and distant duty." Kauffman's other volunteers came from the U.S. Marines and U.S. Army combat engineers. Training commenced with one grueling week designed to "separate the men from the boys". Some said that "the men had sense enough to quit, leaving Kauffman with the boys." It was and is still considered the first "Hell Week". Normandy In early November 1943, NCDU-11 was assigned as the advance NCDU party for Operation Overlord. They would be joined in England by 33 more NCDUs. They trained with the 146th, 277th, and 299th Combat Engineers to prepare for the landing. As more teams arrived, a NCDU Command was created for NCDUs: 11, 22–30, 41–46, 127–8, and 130–42. & French Croix de Guerre with Palm, while MM2 Meyers received a Silver Star. Two men were wounded and one was killed. The Germans had constructed elaborate defenses on the French coast. These included steel posts driven into the beach and topped with explosive charges. Large 3-ton steel barricades, called Belgian Gates and hedgehogs, were placed throughout the tidal zone. Behind which was a network of reinforced coastal artillery, mortar and machine gun positions. The NCDU teams (designated Demolitions Gap-Assault teams) would come in at low tide to clear the obstacles. Their mission was to open sixteen wide corridors for the landing at each of the U.S. landing zones (Omaha Beach and Utah Beach). Unfortunately, the plans were not executed as laid out. The preparatory air and naval bombardment was ineffective, leaving many German guns to fire on the assault. Also, tidal conditions caused difficulties for the NCDUs. Despite heavy German fire and casualties, the NCDUs charges opened gaps in the defenses. As the infantry came ashore, some used obstacles for cover that had demolition charges on them. The greatest difficulty was on Omaha Beach. By nightfall, thirteen of the planned sixteen gaps were open. Of the 175 NCDU men that landed, 31 were killed, and 60 were wounded. The attack on Utah Beach was better, four dead and eleven wounded. A few were temporarily attached to UDTs. Later, NCDUs 1–10 were combined to form Underwater Demolition Team Able. This team was disbanded with NCDUs 2 and 3, plus three others assigned to MacArthur's 7th Amphibious force, and were the only NCDUs remaining at war's end. The other men from Team Able were assigned to numbered UDTs. == Underwater Demolition Teams During WWII ==

The first units designated as Underwater Demolition Teams were formed in the Pacific Theater. Rear Admiral Turner, the Navy's amphibious expert, ordered the formation of Underwater Demolition Teams in response to the assault debacle experienced at Tarawa. Turner recognized that amphibious operations required intelligence of underwater obstacles. They were deployed in every major amphibious landing after Tarawa with 34 teams eventually being commissioned. Teams 1–21 were the teams that had deployed operationally, with slightly over half of the officers and enlisted coming from the Seabees in those teams. The remaining teams were not deployed due to the war ending. Tarawa and the formation of UDTs Prior to Tarawa, both Naval and Marine Corps planners had identified coral as an issue for amphibious operations. At Tarawa the neap tide created draft issues for the Higgins boats (LCVPs) clearing the reef. The Amtracs carrying the first wave crossed the reef successfully. The LCVPs carrying the second wave ran aground, disembarking their Marines several hundred yards to shore in full combat gear, under heavy fire. Many drowned or were killed before making the beach, forced to wade across treacherously uneven coral. The first wave was left fighting without reinforcements and took heavy casualties on the beach. This disaster made it clear to Admiral Turner that pre-assault intelligence was needed to avoid similar difficulties in future operations. To that end, Turner ordered the formation of underwater demolition teams to do reconnaissance of beach conditions and do removal of submerged obstructions for Amphibious operations. Lt. Crist started by recruiting others he had blasted coral with in CB 10 and by the end November 1943 he had assembled close to 30 officers and 150 enlisted men from the 7th Naval Construction Regiment, UDT 1 was tasked with two daylight recons. The men were to follow Marine Corps Recon procedure with each two-man team getting close to the beach in an inflatable boat to make their observations wearing fatigues, boots, d helmets, and life-lined to their boats. Team 1 found that the reef kept them from ascertaining conditions both in the water and on the beach as had been anticipated. In keeping with the Seabee traditions of: (1) doing whatever it takes to accomplish the job and (2) not always following military rules to get it done, UDT 1 did both: the fatigues and boots came off. Ensign Lewis F. Luehrs and Seabee Chief Bill Acheson had anticipated that they would not be able to get the intel Admiral Turner wanted following USMC Recon protocol and had worn swim trunks beneath their fatigues. (Seabees). UDT 2 was sent to Roi-Namur where Lt. Crist earned a Silver Star. UDTs 1 and 2 were decommissioned upon return to Hawaii with most of the men transferred to UDTs 3, 4, 5, and 6. Admiral Turner ordered the formation of nine teams, three for III Amphibious Corps and six for V Amphibious Corps (in all Teams 3–11). As more NCDUs arrived in the Pacific they were used to form even more teams. UDT 15 was an all-NCDU team. To implement these changes and grow the UDTs, Koehler was made the commanding officer of the Naval Combat Demolition Training and Experimental Base on Maui. Admiral Turner also brought on LCDR Draper Kaufmann as a combat officer. That was unprecedented in U.S. Naval/Marine Corps history. For UDTs 3 and 4 all officers received a silver stars and all the enlisted received bronze stars with Vs for Operation Forager (Guam). assignment while UDT 8 went to Angaur. The officers were almost all CEC and the enlisted were Seabees. At formation UDT 10 was assigned 5 officers and 24 enlisted that had trained as OSS Operational Swimmers (Maritime Unit: Operational Swimmer Group II). They were led by a Lt. A.O. Chote Jr., who became UDT 10's commanding officer. The men were multi-service: Army, Coast Guard, Marine Corps and Navy but the OSS was not allowed to operate in the Pacific Theater. Admiral Nimitz needed swimmers and did approve their transfer from the OSS to his operational and administrative control. Most of their OSS gear was stored as it was not applicable to UDT work however, their swimfins came with them. The other UDTs quickly adopted them. UDT 14 was the first all-Navy team (one of three from the Pacific fleet) even though its CO and XO were CEC and some of Team Able was incorporated. In the Philippines Leyte Gulf UDTs 10 & 15 reconnoitered beaches at Luzon, teams 3, 4, 5, & 8 were sent to Dulag and teams 6, 9, & 10 went to Tacloban. When UDT 3 returned to Maui the team was made the instructors of the school. Lt Crist was again made Training Officer. Under his direction training was broken into four 2-week blocks with an emphasis on swimming and reconnaissance. Lt Cmdr. Vincent Moranz of UDT 13 was "reluctant, and radioed that his men ... were not salvage-men. During WWII the Navy did not have a rating for the UDTs nor did they have an insignia. Those men with the CB rating on their uniforms considered themselves Seabees that were doing underwater demolition. They did not call themselves "UDTs" or "Frogmen" but rather "Demolitioneers" which had carried over from the NCDUs and LtCdr Kauffmans recruiting them from the Seabee dynamiting and demolition school. UDTs had to meet the military's standard age guidelines, Seabees older could not volunteer. In preparation for the invasion of Japan the UDTs created a cold water training center and mid-1945 UDTs had to meet a "new physical standard". UDT 9 lost 70% of the team to this change. The last UDT demolition operation of the war was on 4 July 1945 at Balikpapan, Borneo. The UDTs continued to prepare for the invasion of Japan until VJ Day when the need for their services ceased. With the draw-down from the war two half-strength UDTs were retained, one on each coast: UDT Baker and UDT Easy. However, the UDTs were the only special troops that avoided complete disbandment after the war, unlike the OSS Maritime Unit, the VAC Recon Battalion, and several Marine recon missions. In 1942 the Seabees became a completely new branch of the United States War Department. The Marine Corps provided both training and an organizational model. Something that either was not shared or the Seabees chose to ignore or considered not important was the keeping of logs, journals and records. The Seabees brought this record keeping approach with to the NCDUs and UDTs. ==After World War II==

Japan occupation should receive the first surrendered sword. On 20 August 1945 embarked UDT 21 at Guam as a component of the U.S. occupation force heading for Japan. Orders arrived for Begor to return the team to San Diego on 27 September. China With the war over thousands of Japanese troops remained in China. The issue was given to the Marine's III Marine Amphibious Corps. UDT 9 was assigned to Operation Beleaguer to recon the landings of the 1st Marine Division at Taku and Qingdao the first two weeks of October 1945. On their way to China the Navy had UDT 8 carry out a mission at Jinaen, Korea 8–27 September 1945. Operation Crossroads Bikini Atoll was chosen for the site of the nuclear tests of Operation Crossroads."In March 1946, Project Y scientists from Los Alamos decided that the analysis of a sample of water from the immediate vicinity of the nuclear detonation was essential if the tests were to be properly evaluated. After consideration of several proposals to accomplish this, it was finally decided to employ drone boats of the type used by Naval Combat Demolition Units in France during the war". UDT Easy, later named UDT 3, was given the designation TU 1.1.3 for the Operation and was assigned the control and maintenance of the drone boats. On 27 April, 7 officers and 51 enlisted men embarked the at the Seabee base Port Hueneme, CA, Begor came to have the reputation as the most contaminated boat in the fleet. Submersible Operations Post WWII the UDTs continued to research new techniques for underwater and shallow-water operations. One area was the use of SCUBA equipment. Dr. Chris Lambertsen had developed the Lambertsen Amphibious Respiratory Unit (LARU), an oxygen rebreather, which was used by the Maritime Unit of the OSS. In October 1943, he demonstrated it to LtCmdr. Kauffman, but was told the device was not applicable to current UDT operations. Dr. Lambertsen and the OSS continued to work on closed-circuit oxygen diving and combat swimming. When the OSS was dissolved in 1945, Lambertsen retained the LARU inventory. He later demonstrated the LARU to Army Engineers, the Coast Guard, and the UDTs. In 1947, he demonstrated the LARU to LtCmdr. Francis "Doug" Fane, then a senior UDT commander. LtCmdr. Fane was enthusiastic for new diving techniques. He pushed for the adoption of rebreathers and SCUBA gear for future operations, but the Navy Experimental Diving Unit and the Navy Dive School, which used the old "hard-hat" diving apparatus, declared the new equipment be too dangerous. Nonetheless, LtCmdr. Fane invited Dr. Lambertsen to NAB Little Creek, Virginia in January 1948 to demonstrate and train UDT personnel in SCUBA operations. This was the first-ever SCUBA training for USN divers. Following this training, Lcdr. Fane and Dr. Lambertsen demonstrated new UDT capabilities with a successful lock-out and re-entry from , an underway submarine, to show the Navy's need for this capability. LtCmdr. Fane then started the classified "Submersible Operations" or SUBOPS platoon with men drawn from UDT 2 and 4 under the direction of Lieutenant (junior grade) Bruce Dunning. LtCmdr. Fane also brought the conventional "Aqua-lung" open-circuit SCUBA system into use by the UDTs. Open-circuit SCUBA is less useful to combat divers, as the exhausted air produces a tell-tale trail of bubbles. However, in the early 1950s, the UDTs decided they preferred open-circuit SCUBA, and converted entirely to it. The remaining stock of LARUs was supposedly destroyed in a beach-party bonfire. Later on, the UDT reverted to closed-circuit SCUBA, using improved rebreathers developed by Dr. Lambertsen. It was at this time that the UDTs, led by LtCmdr. Fane, established training facilities at Saint Thomas in the Virgin Islands. The UDTs also began developing weapons skills and procedures for commando operations on land in coastal regions. The UDTs started experiments with insertion/extraction by helicopter, jumping from a moving helicopter into the water or rappelling like mountain climbers to the ground. Experimentation developed a system for emergency extraction by plane called "Skyhook". Skyhook utilized a large helium balloon and cable rig with harness. A special grabbing device on the nose of a C-130 enabled a pilot to snatch the cable tethered to the balloon and lift a person off the ground. Once airborne, the crew would winch the cable in and retrieve the personnel though the back of the aircraft. Training this technique was discontinued following the death of a SEAL at NAB Coronado during a training exercise. Teams still utilize the Skyhook for equipment extraction and retain the combat capability for personnel if needed. == Korean War ==

During the Korean War, the UDTs operated on the coasts of North Korea, with their efforts initially focused on demolitions and mine disposal. Additionally, the UDT accompanied South Korean commandos on raids in the North to demolish railroad tunnels and bridges. The higher-ranking officers of the UDT frowned upon this activity because it was a non-traditional use of the Naval forces, which took them too far from the water line. Due to the nature of the war, the UDT maintained a low operational profile. Some of the better-known missions include the transport of spies into North Korea, and the destruction of North Korean fishing nets. A more traditional role for the UDT was in support of Operation CHROMITE, the amphibious landing at Inchon. UDT 1 and UDT 3 divers went in ahead of the landing craft, scouting mud flats, marking low points in the channel, clearing fouled propellers, and searching for mines. Four UDT personnel acted as wave-guides for the Marine landing. The UDT assisted in clearing mines in Wonsan harbor, under fire from enemy shore batteries. Two minesweepers were sunk in these operations. A UDT diver dove on the wreck of , the first U.S. combat operation using SCUBA gear. The Korean War was a period of transition for the men of the UDT. They tested their previous limits and defined new parameters for their special style of warfare. These new techniques and expanded horizons positioned the UDT well to assume an even broader role as war began brewing to the south in Vietnam. HS-6 recover operations – S65-33491 == NASA ==

Initially, the splashdown of U.S. crewed space capsules were unassisted. That changed quickly after the second crewed flight; when Mercury 11 hit the water following reentry, the hatch blew and she sank, nearly drowning Gus Grissom. All Mercury, Gemini, and Apollo space capsules were subsequently met by UDTs 11 or 12 upon splashdown. Before the hatch was opened, the UDTs would attach a flotation collar to the capsule and liferaft for the astronauts to safely exit the craft. == Vietnam War ==

The Navy entered the Vietnam War in 1958, when the UDTs delivered a small watercraft far up the Mekong River into Laos. In 1961, naval advisers started training South Vietnamese personnel in South Vietnam. The men were called the Liên Đoàn Người Nhái (LDNN) or Vietnamese Frogmen, which translates as "Frogmen Team". UDT teams carried out hydrographic surveys in South Vietnam's coastal waters and reconnaissance missions of harbors, beaches and rivers often under hazardous conditions and enemy fire. Later, the UDTs supported the Amphibious Ready Groups operating on South Vietnam's rivers. UDTs manned riverine patrol craft and went ashore to demolish obstacles and enemy bunkers. They operated throughout South Vietnam, from the Mekong Delta (Sea Float), the Parrot's Beak and French canal AO's through I Corps and the Song Cui Dai estuary south of Da Nang. == Birth of Navy SEALs ==

In the mid-1950s, the Navy saw how the UDT's mission had expanded to a broad range of "unconventional warfare", but also that this clashed with the UDT's traditional focus on maritime operations swimming, boat, and diving operations. It was therefore decided to create a new type of unit that would build on the UDT's elite qualities and water-borne expertise, but would add land combat skills, including parachute training and guerrilla/counterinsurgency operations. These new teams would come to be known as the US Navy SEALs, an acronym for Sea, Air, and Land. Initially there was a lag in the unit's creation until President John F. Kennedy took office. Kennedy recognized the need for unconventional warfare, and supported the use of special operations forces against guerrilla activity. The Navy moved forward to establish its new special operations force and in January 1962 commissioned SEAL Team ONE in NAB Coronado and SEAL Team TWO at NAB Little Creek. In 1964, Boat Support Unit ONE was established, designed to directly support NSW operations, and was initially outfitted primarily by UDTs and newly established SEALs. UDT-11 & 12 were still active on the west coast and UDT-21 & 22 on the east coast. The SEALs quickly earned a reputation for valor and stealth in Vietnam, where they conducted clandestine raids in perilous territory. Reorganization From 1974–1975, UDT 13 was redesignated; some personnel established Underwater Construction Teams, while others joined the special boat detachment. In May 1983, the remaining UDT teams were reorganized as SEAL teams. UDT 11 became SEAL Team Five and UDT 12 became Seal Delivery Vehicle Team One. UDT 21 became SEAL Team Four and UDT 22 became Seal Delivery Vehicle Team Two. A new team, SEAL Team Three was established in October 1983. Since then, teams of SEALs have taken on clandestine missions in war-torn regions around the world, tracking high-profile targets such as Panama's Manuel Noriega and Colombian drug lord Pablo Escobar, and playing integral roles in the wars in Iraq and Afghanistan. Though reorganized as SEAL Teams, the UDT heritage remains. For example, the National Navy UDT-SEAL Museum opened in 1985. The UDT-SEAL Association, chartered as a Veterans Service Organization in 2013, includes Naval Combat Demolition Units, Amphibious Scouts and Raiders, OSS Maritime Units, Underwater Demolition Teams, SEAL Teams, and SEAL Delivery Vehicle Teams as "Combat Swimmer" units, categorizes them as "The Teams", and offers only such personnel regular association membership. The long-term administrative transition is also found between the legacy UDT Navy Enlistment Classification (NEC) and the more modern SEAL NEC. For example, the 1993 DoD Occupational Conversion Index continued to classify SEAL NEC 5326 under the UDT/EOD occupation heading. A 1997 Office of the Secretary of Defense study used the umbrella NEC 532X to refer to Special Warfare Combatant Swimmers, incorporating the defunct UDT NEC of 5321 and SEAL NEC 5326. The 2003 Naval Education and Training publication 14504 stated, "The Navy special warfare community includes enlisted personnel qualified for assigned secondary NECs 5321 [and] 5326...Once qualified, personnel maybe assigned...as underwater demolition/sea-air-land (UDT/SEAL) team operators". In 2005, Navy Milpersman 1220-010 removed the reference to NEC 5321 and explicitly used NEC 532X as the Sea-Air-Land Operators (SEAL) designator. This is consistent with the UDT-SEAL Association charter, which defines the 532X classification as a "SEAL operator NEC". ==Badge==

In October 1969, the U.S. Navy authorized the Underwater Demolition insignia for those who had served in an UDT. However, this UDT badge was phased out in 1971, as was the silver badge for enlisted SEAL and Underwater Demolition Team members. After that, SEAL and UDT operators, both officer and enlisted, were all awarded the same gold Navy Special Warfare Insignia (known as the "SEAL Trident"), as well as gold Navy jump wings. UDT members who had received the legacy insignia were authorized to apply for the superceding Navy Special Warfare device. Although the UDT insignia was short-lived and superseded by the SEAL Trident, its symbolism endured. In 2006, the Navy would create the Special Warfare Operator (SO) rating with a specialty mark identical to the defunct UDT badge. This heraldry directly ties the historic Underwater Demolition Team legacy to modern day Navy SEALs. == Unit awards ==

The UDTs have received several unit citations and commendations. Members who participated in actions that merited the award are authorized to wear the medal or ribbon associated with the award on their uniform. Awards and decorations of the United States Armed Forces have different categories, (i.e. Service, Campaign, Unit, and Personal). Unit Citations are distinct from the other decorations. Naval Combat Demolition Force O (Omaha beach) Normandy •   Presidential Unit Citation Normandy Naval Combat Demolition Force U (Utah beach): Normandy •   Navy Unit Commendation: Normandy UDT 4 •   Navy Unit Commendation: Guam •   Presidential Unit Citation: Bruni Bay, Borneo 1969 • Republic of Vietnam Gallantry Cross with Palm Unit Award •   Navy Meritorious Unit Commendation: Vietnam 1969 • OPNAV NOTICE 1650, MASTER LIST OF UNIT AWARDS AND CAMPAIGN MEDALS ==Fiction==

• The Frogmen (1951), starring Dana Andrews and Richard Widmark. World War II film based on the Underwater Demolition Teams. Contemporary UDT members appear in several sequences. • Underwater Warrior (1958) directed by Andrew Marton is based on the memoirs of Lieutenant-Commander Francis Douglas Fane, Naked Warriors. ==See also==