After shakedown in the Caribbean and along the Latin American coast to the Canal Zone, Ecuador, and Colombia, Halfbeak spent the next 3 years in training operations and fleet exercises out of New London, Conn., where she was part of SubRon 8.

Fitted with a snorkel to enable her to stay submerged for long periods of time and distinguished by a greatly streamlined superstructure, Halfbeak left Portsmouth 13 January 1950 to work with the Research and Development Group at New London.

A similar cruise in 1956 was punctuated by the Suez Crisis, and Halfbeak remained in the eastern Med operating with the 6th Fleet until January 1957 helping to maintain the peace in that crucial region.

Her duties took another turn as 28 July 1958 she departed for the Arctic, where with the nuclear submarine Skate she operated under and around the polar ice pack to gather information in connection with the International Geophysical Year.

During these operations, Skate sailed under the Arctic ice pack to reach the North Pole 11 August and continued to cruise freely there repeating the visit 6 days later.