When she was finally decommissioned in 2004, after 31 years and 19 deployments, USS Parche was the most decorated submarine in US Navy history.
SSN-683 Parche was built as a Sturgeon Class attack submarine but was modified over the years, becoming a spy-submarine par-excellence. Despite details still being classified, it is treated as fact that Parche conducted covert intelligence operations in the proximity of the Soviet Union during the Cold War, and other countries of interest in the years since.
After a brief career as a regular attack submarine based on the East Coast, Parche was transferred to the West Coast and went in for an extensive refit at Mare Island. The refit enabled her to perform ‘special missions’.
Most of the modifications were hidden below the waterline but the diver’s chamber, taken from the retired USS Halibut, was attached over the aft escape trunk. Known as ‘the can’ this was disguised as a DSRV (deep sea rescue vehicle) simulator exactly as on Halibut.
Below the waterline a skirt was added with retractable skegs per USS Seawolf. Side thusters were added in the lower ballast tanks to enable her to hover and position herself exactly on the seafloor. Small ‘Sonar fish’ could be deployed through the torpedo tubes, and there was possibly an external locker for submarine communications cable (SCC) taps. This was most likely Parche’s primary espionage mission, laying and retrieving wire taps on Soviet communications cables in the Sea of Okhotsk in the Pacific and Barents Sea and White Sea on the Atlantic side.

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