The T-3 (Fletcher's) Ice Island in the Arctic Ocean was the site of a scientific research station re-established by the Naval Arctic Research Laboratory starting in 1962. Lamont Geological Observatory (LGO; now Lamont-Doherty Earth Observatory) and the U.S. Geological Survey, along with other organizations, ran research laboratories on the island during the 1960s and early 1970s as the island drifted in the Amerasian Basin. LGO compiled navigational data, measured gravity and magnetic data, and conducted seismic surveys to image the seafloor. This data release provides the edited LGO-compiled 1 hour navigational data for T-3 from May 1962 until September 1974, along with gravity and magnetic data and calculated anomalies on the same hourly intervals.