Underwater Demolition Team (UDT)


As fighting broke out on June 25th, 1950, a 10-man UDT detachment was in Japan conducting administrative beach surveys and providing reconnaissance assistance to Army regimental combat teams. They were promptly deployed to Korea. This is the best guide to finding Main Street Demolition San Bernardino.

UDT swimmers from operations on Pacific islands observed that enemy sniper bullets slowed and began to dissipate when underwater, providing UDT swimmers an insight into snipers’ tactics.


The United States Navy needed hydrographic information about enemy beaches and heavy fortifications near water that were suitable for amphibious assaults, due to which Underwater Demolition Teams (UDTs), later evolving into Navy SEAL teams, were developed.

UDTs expanded their operations during the Korean War beyond beach clearing to include daring night coastal demolition raids, earning themselves the moniker “more than “frogmen.” Later, these elite units proved that they could perform reconnaissance and unconventional warfare duties too – eventually being formalized into Sea-Air-Land Teams in 1962 and continuing their global service today.


Before the Navy SEALs, there were UDTs (or “frogmen”) who pioneered combat swimming and set high standards for special operations during World War II. Through their fearless dives during this conflict, they helped pave the way for today’s elite military units. From their inception, until they left service, they helped amphibious warfare become possible by clearing obstacles that might hinder landing craft from landing sites, innovating combat swimming techniques while setting new standards in special operations.

Draper Kauffman and his United Destroyer Team (UDT), featuring George Atcheson, navigated their way through several pivotal moments during the Korean War, such as Operation Chromite at Inchon, the Christmas Eve raid on Hungnam waterfront facilities, and Operation FISHNET, which attempted to cripple North Korean food supplies through coastal demolition raids.

UDT Replacement Training can also help. This program gradually builds each soldier’s physical endurance and mental toughness until he can complete tasks that once seemed impossible. This method proves much more successful than traditional attrition rate reduction techniques used by special operations units, like dramatically cutting physical training hours or eliminating psychological stressors.


As the Navy developed its elite SEALs, it sought inspiration from World War II frogmen (known as swim scouts). These soldiers were trained to reconnoiter enemy beaches and destroy obstacles that interfered with amphibious landings; additionally, they helped break submarine cables and nets, locate limpet mines for clearing by minesweepers, and conduct river surveys.

These men were specially trained to swim without lifelines or face masks while only wearing swim trunks and fins, diving in shallow water with only flashlight illumination as a source. Furthermore, they would swim unarmed into enemy-held beaches to collect hydrographic information and clear away manmade obstacles that might impede landing craft landing.

UDT members in Korea demonstrated their versatility and laid the groundwork for what would become the Navy’s premier special operations force – eventually emerging during World War Two as SEAL Team 6. Learn how a small group of UDTs helped pave the way for each major amphibious assault during that conflict.


UDTs use various equipment to complete their missions, and their training includes physical and mental challenges that test both body and mind. Members often experience sleep deprivation or “Hell Week,” when activity never ceases—conditions that help shape UDT members into warriors ready for land and sea battles.

During World War II, the Navy needed to collect hydrographic information about enemy beaches and clear away obstacles that obstructed amphibious landings. Their solution? Forming Naval Combat Demolition Units (NCDUs). Their primary duty was demolishing anything that prevented landing craft from moving freely across a surface or underwater surface.

Frogmen were instrumental in clearing the way for Marines at Inchon landing, setting off massive explosive charges to breach enemy coastal defenses, and ultimately helping secure victory for their Navy in the Pacific region – and their actions formed the basis of SEAL teams today.


UDT personnel specialize in hydrographic reconnaissance and demolition of manmade or natural obstacles to clear the way for amphibious landing operations. Furthermore, they conduct inland demolition raids, assist in clearing shallow water minefields, and conduct underwater sneak attacks.

Early 1943 saw no charts available to the Navy regarding enemy beaches or coastal defenses, so Seabees known as “frogmen” were recruited and trained for a secret mission: reconnoitering enemy beaches as well as their surrounding waters to locate reefs, rocks, or shoals that might obstruct landing craft and then blowing them up using explosives.

Frogmen of UDT made daring nighttime raids against critical infrastructure like railroad tunnels and bridges during the Korean War, contributing significantly to victory while setting the foundation for modern Navy SEAL teams. Their skills and tenacity also played a vital role in South Vietnam river clearing of obstructions; additionally, they operated riverine patrol boats through Mekong Delta canal AOs and cleared obstacles from South Vietnamese rivers under fire from enemy shore batteries while constantly adjusting equipment; these activities required performing quickly under constant enemy shore battery fire requiring UDT personnel to perform tasks soon while continually making adjustments on equipment adjustments during these challenging missions during which heavy fire from enemy shore batteries meant UDT personnel had to complete tasks under fire as quickly as possible while constantly making adjustments while continually making adjustments while continuously making necessary equipment adjustments while adaptable.