Underwater Demolition Teams
Shoulder sleeve patch of the Underwater Demolition Teams
Active	August 15, 1942 - January 1, 1962
Branch	United States Navy
Type	SOF
Role	reconnaissance, infiltrating and exfiltrating by sea, underwater demolition, intelligence gathering
Garrison/HQ	Fort Pierce Maui
Nickname	UDT
Battles/wars	Operation Overlord Korean War Battle of Iwo Jima Battle of Okinawa Operation Torch Borneo campaign (1945) Battle of Peleliu Battle of Saipan Battle of Tinian Battle of Guam Battle of Leyte Gulf Invasion of Lingayen Gulf

Underwater Demolition Teams (UDT) were a precursor to the current United States Navy SEALs. The first group of volunteers selected from the Naval Construction Battalions (Seabees) in the spring of 1943. These volunteers were organized into special teams called "Navy Combat Demolition Units" (NCDUs). The units were tasked with reconnoitering and clearing beach obstacles for troops going ashore during amphibious landings, and evolved into Combat Swimmer Reconnaissance Units; this is a type of frogman operation. Their first issue breathing set was this type of rebreather designed by Christian J. Lambertsen. Image File history File links Underwater_Demolition_Teams_shoulder_sleeve_patch. ... August 15 is the 227th day of the year in the Gregorian Calendar (228th in leap years), with 138 days remaining. ... 1942 (MCMXLII) was a common year starting on Thursday (the link is to a full 1942 calendar). ... January 1 is the first day of the calendar year in both the Julian and Gregorian calendars. ... 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar). ... USN redirects here. ... The United States Special Operations Forces is the official category where the U.S. Department of Defense lists the U.S. military units that have a training specialization in unconventional warfare and special operations. ... Mixed reconnaissance patrol of the Polish Home Army and the Soviet Red Army during Operation Tempest, 1944 Reconnaissance is the military term for the active gathering of information about an enemy, or other conditions, by physical observation. ... Underwater demolition refers to the destruction or neutralization of man-made or natural underwater obstacles. ... Fort Pierce is a city located in St. ... Maui is the second-largest of the Hawaiian Islands at 727 square miles (1883 km²). Native Hawaiian tradition gives the origin of the islands name in the legend of Hawaiiloa, the Polynesian navigator attributed with discovery of the Hawaiian Islands. ... The Battle of Normandy was fought in 1944 between the German forces occupying Western Europe and the invading Allies. ... Combatants United Nations: Republic of Korea United States United Kingdom Canada Australia The Netherlands France Philippines Turkey Ethiopia Communist states: Democratic People’s Republic of Korea People’s Republic of China Soviet Union Commanders Syngman Rhee Chung Il Kwon Douglas MacArthur Mark W. Clark Matthew Ridgway Kim Il-sung Choi... Combatants United States Empire of Japan Commanders Holland Smith Tadamichi Kuribayashi † Strength 77,000 marines 100,000 total 20,700 infantry Casualties 6,821 dead 20,000 wounded 18,000 dead 1,083 survived The Battle of Iwo Jima (Operation Detachment) was fought between the United States of America and... Combatants United States United Kingdom (naval involvement only) Empire of Japan Commanders Simon Bolivar Buckner† Joseph Stilwell Mitsuru Ushijima† Strength 548,000 marines 107,000 regulars 24,000 militia Casualties 12,500 killed or missing 38,000 wounded 33,096 non-combat wounded 38 ships lost 763 aircraft lost 110... Combatants United States United Kingdom Free French Forces Germany Vichy France Commanders Dwight Eisenhower Andrew Cunningham Erwin Rommel François Darlan Strength 73,500 - Casualties 479+ dead 720 wounded 1346+ dead 1997 wounded Operation TORCH (initially called Operation GYMNAST) was the British-American invasion of French North Africa in World... The Borneo campaign of 1945 was the last major Allied campaign in the South West Pacific Area, during World War II. In a series of amphibious assaults between May 1 and July 21, the Australian I Corps, under General Leslie Morshead, attacked Japanese forces occupying the island. ... Like the bloody World War II island campaigns before it, the battle of Peleliu was a fight to capture an airstrip on a speck of coral in the western Pacific. ... Combatants United States Japan Commanders Richmond K. Turner, Holland Smith Yoshitsugu Saito Strength 71,000 31,000 Casualties 3,426 killed; 13,160 wounded 24,000 KIA and 5,000 suicides; 921 prisoners The battle of Saipan was a battle of the Pacific campaign of World War II, fought on... The battle of Tinian was a battle of the Pacific campaign of World War II, fought on the island of Tinian in the Mariana Islands from 24 July 1944 to 1 August 1944. ... The battle of Guam was a battle of the Pacific campaign of World War II, fought on the island of Guam in the Mariana Islands from 21 July 1944 to 10 August 1944. ... Combatants United States British Empire Australia various others Empire of Japan Commanders William Halsey, Jr Jisaburo Ozawa Strength 17 aircraft carriers 18 escort carriers 12 battleships 24 cruisers 141 destroyers and destroyer escorts Many PT boats, submarines and fleet auxiliaries About 1,500 planes 4 aircraft carriers 9 battleships 19... Combatants United States Empire of Japan Commanders Walter Krueger Tadamichi Kuribayashi Strength 68,000 unknown Casualties none none The Invasion of Lingayen Gulf was an American amphibious operation of WWII carried out in the Phillipines. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... The official motto of the Seabees, the United States Navy Construction Battalions, is Construimus, Batuimus—We Build, We Fight. ... The Seabees are the Construction Battalions of the United States Navy. ... 1943 (MCMXLIII) was a common year starting on Friday (the link is to a full 1943 calendar). ... Mixed reconnaissance patrol of the Polish Home Army and the Soviet Red Army during Operation Tempest, 1944 Reconnaissance is the military term for the active gathering of information about an enemy, or other conditions, by physical observation. ... This article is about a military strategy involving land troops dispatched from naval ships. ... // This page describes a type of scuba diver. ... Inspiration closed circuit diving rebreather A rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycles exhaled gas. ... Dr. Christian J. Lambertsen developed US Navy frogmens rebreathers in the early 1940s for underwater warfare. ...

The NCDUs distinguished themselves during World War II in both the Atlantic and Pacific theaters. In 1947, the Navy organized its first underwater offensive strike units. During the Korean Conflict, these Underwater Demolition Teams (UDTs) took part in the landing at Inchon as well as other missions including demolition raids on bridges and tunnels accessible from the water. They also conducted limited minesweeping operations in harbors and rivers. Combatants Major Allied powers: United Kingdom Soviet Union United States Republic of China and others Major Axis powers: Nazi Germany Italy Japan and others Commanders Winston Churchill Joseph Stalin Franklin Roosevelt Harry Truman Chiang Kai-Shek Adolf Hitler Benito Mussolini Hideki Tojo Casualties Military dead: 17,000,000 Civilian dead... 1947 (MCMXLVII) was a common year starting on Wednesday (the link is to a full 1947 calendar). ... The Korean War (Korean: 한국전쟁), from June 25, 1950 to July 27, 1953, was a conflict between North Korea and South Korea. ... Incheon Metropolitan City is a metropolitan city and major seaport on the west coast of South Korea, near Seoul. ...

During the 1960s, each branch of the armed forces formed its own counterinsurgency force. The Navy utilized UDT personnel to form separate units called SEAL teams. Concurrently, Naval Operations Support Groups were formed to aid UDTs, SEALs, and two other unique units (Boat Support and Beach Jumpers) in administration, planning, research, and development. During the Vietnam War, UDTs performed reconnaissance missions. The 1960s decade refers to the years from January 1, 1960 to December 31, 1969, inclusive. ... An insurgency is an armed rebellion against a constituted authority, by any irregular armed force that rises up against an enforced or established authority, government, or administration. ... Look up Administration in Wiktionary, the free dictionary. ... Combatants Republic of Vietnam United States Republic of Korea Thailand Australia New Zealand The Philippines National Front for the Liberation of South Vietnam Democratic Republic of Vietnam People’s Republic of China Democratic Peoples Republic of Korea Strength US 1,000,000 South Korea 300,000 Australia 48,000... Mixed reconnaissance patrol of the Polish Home Army and the Soviet Red Army during Operation Tempest, 1944 Reconnaissance is the military term for the active gathering of information about an enemy, or other conditions, by physical observation. ...

In 1967, the Naval Operations Support Groups were renamed "Naval Special Warfare Groups" (NSWGs) as involvement increased in special operations. 1967 (MCMLXVII) was a common year starting on Sunday of the Gregorian calendar (the link is to a full 1967 calendar). ... Special forces or special operations forces is a term used to describe relatively small military units raised and trained for reconnaissance, unconventional warfare and special operations. ...

In 1983, existing UDTs were re-designated as "SEAL teams" or "SEAL Delivery Vehicle Teams" and the requirement for hydrographic reconnaissance and underwater demolition became "SEAL missions". 1983 (MCMLXXXIII) was a common year starting on Saturday of the Gregorian calendar. ... Mixed reconnaissance patrol of the Polish Home Army and the Soviet Red Army during Operation Tempest, 1944 Reconnaissance is the military term for the active gathering of information about an enemy, or other conditions, by physical observation. ...

For those who served in an Underwater Demolition Team, the U.S. Navy authorized a military badge known as the Underwater Demolition Badge. The badge was phased out and eventually replaced by the Special Warfare Badge. In the modern age, the Underwater Demolition Badge is considered obsolete. Military badges of the United States are devices of personal recognition that are granted to service members of the United States armed forces to denote personal accomplishment, qualifications, and participation in designated military campaigns or other activities. ... Underwater Demolition Officer Badge Underwater Demolition Enlisted Badge The Underwater Demolition Badge is an obsolete badge of the United States Navy which was first created during the Second World War. ... SEAL Badge Obsolete Enlisted SEAL Badge The Special Warfare Badge, also known as the “SEAL Trident”, is one of the most recognizable combat badges of the United States Navy. ...

See also

• United States Navy
• United States Special Operations Forces
• Clearance Diving Teams
• Underwater demolition
• United States Navy SEALs

USN redirects here. ... The United States Special Operations Forces is the official category where the United States Department of Defense lists the U.S. military units that have a training specialisation in unconventional warfare and special operations. ... The Clearance Diving Teams are similar to Americas former Underwater Demolition Teams (UDT) teams in terms of function and capabilities. ... Underwater demolition refers to the destruction or neutralization of man-made or natural underwater obstacles. ... This article or section does not cite its references or sources. ...

External links

• Navy UDT-SEAL Museum
• Roll of honour, awards and images.