Like her sisters in the USN submarine fleet, USS Burrfish continued to seek out the enemy in the far-flung reaches of the Pacific. Her third war patrol was a historic one, commencing on 11th of July and continuing until he 27th of August, 1944.
Sailing from Pearl Harbour in the Hawaiian Islands, the boat had on board five members of Underwater Demolition Team 10 as well as a chief petty officer and a lieutenant from the UDT training staff. The UDT had with them inflatable rubber boats which were carried in free-flooding tanks on Burrfish's after deck.
On the 9th of August two teams of two men each swam ashore and gathered intelligence on the beach of Peleliu. The four swimmers plus their fifth member who had stood by in the inflated boat returned safely to Burrfish, waiting in deep water.
A second beach reconnaissance was carried out on August 18th, but was ill-fated. One team of two did not return to the waiting inflatable, and one of their mates swam in to try to assist. The men were not seen again. Burrfish searched for the three men until the night of August 20th to no avail, and was forced to leave the area. All three were captured by the Japanese and reportedly tortured and executed.
The Burrfish had carried out the only USN submarine-launched Underwater Demolition Team beach reconnaissance of the Second World War.