This mysterious little midget was photographed in the CIA Museum in McLean, Virginia in 2011.
From the official description:
CIA designed and manufactured this two-man semi-submersible in the 1950s. It carried no weapons, was cramped, had limited endurance, and required a “mother ship” for transport and recovery. However, the vessel could approach areas ships could not.
Then there is the rest of the story.
Codenamed the SKIFF, the craft could be towed to a location and cached at a depth of up to 30 feet below the surface if needed.
Designed in the tail-end of WWII as part of the OSS’s Project NAPKO, these craft were to be used to deposit specially trained Korean Americans and Korean prisoners of war for infiltration into Japanese-occupied Korea, and ultimately into Japan itself. Their mission was to collect intelligence and conduct sabotage in advance of Operation Olympic, the planned US invasion of the Japanese home islands in November 1945.
Half the 2-3 man teams would be landed via nylon boat from fleet submarines coming danger close while the other half would infiltrate via our trusty little submarines towed within 30-40 miles of shore. The little semi-submersibles could be cached just offshore on the seabed and used by (surviving) agents to exfiltrate back to sea.
As noted in a great 11-page article from Studies in Intelligence, the agents would go local:
“Typical of NAPKO missions, the teams were to carry minimal equipment and supplies: 100,000 yen, a radio, appropriate clothing for passing as locals, and a Japanese-manufactured shovel for burying the team’s equipment after landing.”
The boats, built by John Trumpy and Sons of Camden, New Jersey, were termed “Gizmos” and never used, though the Navy did keep them around for awhile, one even lasting long enough to be put on display at the USS Massachusetts in Fall River, incorrectly labeled as a Japanese suicide submarine for years.
In 1953, the CIA thought the concept valid enough to commission two more from Trumpy, codename SKIFFs.
“SKIFF also appears to have come close to operational use, but at least two missions for which it was deployed were canceled.”
Some 19-feet long, the craft drew 2’8″ when buoyant and could ride almost four feet low when semi-submerged, leaving just a foot or so of the low-profile hull above surface. Powered by a 25hp “Atomic Four” gasoline engine with 30-gal tank, the craft could putter along at 5-knots when buoyant or 4.1-kts semisubmerged with a combat radius of 110 nm. The craft weighed 3,650-pound sans crew. Without removing the slabs of ballast, the maximum cargo carried including crew was 608-pounds (exclusive of the weight of two submachine guns). If the ballast was scuttled this could be boosted about another 100 pounds.