[1] Pathfinder was built by the Lake Washington Shipyard of Houghton, Washington with her keel laid 20 February 1941, christened by Eleanor Roosevelt Boettinger, granddaughter of the president, launched 11 January 1942 and completed 31 August 1942 with armament as a request by Navy as the ship's transfer had been approved by Department of Commerce before completion.

[5] A sea-going arm of the U.S. Navy's Hydrographic Office, Pathfinder spent the war years paving the way for amphibious invasion.

At Bougainville, Treasury Island, Green Island, Emirau and Guam, advance Pathfinder parties were sent ashore under the noses of the Japanese to work in close cooperation with Allied amphibious elements in laying out harbor charts or surveying inland channels.

Pathfinder, although nominally a noncombatant, experienced some fifty bombing raids while working close to the front lines.

At the end of September 1944, after some three months of scientific probing around New Guinea, Pathfinder departed for Espiritu Santo, with written commendations from Admirals Nimitz, Kinkaid, and Halsey.

On 6 May 1945 at "Suicide Slot", Sesoko, a Japanese kamikaze plane crash-dived into the veteran survey ship's after gun platform killing one man, starting fires and setting off ready ammunition.