Underwater Demolition Team - After World War II

After World War II

Two half-strength UDTs were retained, one on each coast. Though no combat operations seemed likely, 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 LCDR Kauffman, but was told there was no place in current UDT operations for this radically new device.

However, 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 LCDR Francis "Doug" Fane, then a senior UDT commander.

LCDR 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 it was too dangerous. Nonetheless, 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 Navy divers. Following this training, Fane and Lambertsen demonstrated new UDT capabilities with a successful lock-out and re-entry from USS Grouper (SS-214), an underway submarine, to show the Navy's need for this capability. LCDR Fane then started the classified “Submersible Operations” or SUBOPS platoon with men drawn from UDT 2 and 4 under the direction of LTJG Bruce Dunning.

LCDR 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 Lambertsen.

It was at this time that the UDT (led by Fane) established training facilities at Saint Thomas in the Virgin Islands.

The UDT also began developing weapons skills and procedures for commando operations on land in coastal regions. The UDT 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. This technique was discontinued for training purposes after the death of a SEAL at NAB Coronado on a training lift. The teams still utilize the Fulton Skyhook for equipment extraction and retain the capability for war if an extreme situation requires it.