1964, she conducted Bering Sea Patrol, resupplied Nome station and carried out oceanographic experiments in the Bering Strait and Chukchi Sea. The cutter's crew installed an unmanned oceanographic station in Fairway Rock, Alaska to measure currents in the Bering Strait. She also escorted ships re-supplying the Distant Early Warning Line and laid cables. In July 1965, Northwind, under the command of Captain Kingdrel N. Ayers, conducted an oceanographic survey between Greenland, Iceland, and Scotland and was the first western vessel to operate in the Kara Sea of the Soviet Union, for which she received the Coast Guard Unit Commendation with Operational Distinguishing Device. The (then) classified mission of Northwind was to attempt a transit of the Northeast Passage. This voyage involved transiting the Panama Canal. The effort was not successful and caused a diplomatic incident between the Soviet Union and the United States. In mid-October 1965 Northwind escorted the disabled Swedish MV Orion in the North Atlantic, while in seas, to the Gulf of Saint Lawrence, Canada. In 1966 Northwind returned to Fairway Rock and the crew helped install a Strontium-90 Radioisotope thermoelectric generator (RTG) and additional oceanographic sensors. Northwind then cruised the Laptev Sea and East Siberian Sea doing oceanographic surveys. From July through August 1967, Northwind conducted a current and hydrographic survey in the Bering Strait and resupplied Fairway Rock. During this Bering Sea Patrol, on 23 July 1967, Northwind diverted to respond to the distress call of Canadian Survey Ship (CSS) Richardson of the Canadian Hydrographic Service and was assisted by CCGS Camsell. Richardson was beset in ice northwest of Point Barrow, Alaska; heavily damaged and in imminent danger of loss. As Northwind broke out Richardson, Camsell took the tow and she was taken to Tuktoyaktuk, Northwest Territories for repair. From September to November 1967, Northwind was beset by ice north-northwest of Point Barrow, Alaska. She was freed by , , and . During this cruise Northwind made the northernmost penetration into Arctic pack ice by any surface vessel in history at the time. This mission was the last attempt to resupply T-3, also known as Fletcher's Ice Island station by Northwind with Glacier, John A. Macdonald and Staten Island. Between March and September 1968, she provided ice escort for the National Science Foundation research vessel RV Alpha Helix, then operated by the Scripps Institute of Oceanography at La Jolla, California. This operation was conducted in the