68 Year Ago, the USS COCHINO (SS 343) Was Lost While Attempting to Snorkel in State 4 Seas
We know exactly why the USS COCHINO was lost because the entire crew – less one – survived; saved by the accompanying USS TUSK (SS 426), which lost six men in the rescue effort.
On 25 August 1949, the COCHINO was snorkeling in the Barents Sea in a state 4 sea. Washover intermittently closed the snorkel mast head-valve interrupting ventilation of the boat needed to keep hydrogen generated during a battery charge from reaching the explosive level of four-percent which it did with disastrous results. Multiple explosions with resulting fires occurred, initially at 0801Z with a ”massive explosion” at 0836Z. See link for details.
As previously discussed in several postings on this site – most recently on 3 Aug 17 – the GOLF II Class Soviet SSB K-129 was lost under identical circumstances – attempting to snorkel in massive seas - for the same reason: battery (hydrogen) explosions that occurred at 11:58:58Z, 11:59:43Z and 11:59:47Z on 11 March 1968 with the second event massive.
Although how the battery events were involved in the following ignition of two R21/D4 missiles - which burned to fuel exhaustion within the pressure-hull - cannot be determined from the acoustic data, we do know the initiating events that caused the loss of the K-129 were hydrogen (battery) explosions. The amplitude of the second event – detected at ranges in excess of 1000 nautical mies - indicates the K-129 would have been lost even if the missiles had not ignited.