RRS Shackleton undertook one of the longest voyages of her career between October 1974 and July 1976. After leaving England, she worked in the equatorial and south Atlantic, prior to rounding the Cape of Good Hope into the Indian Ocean, and then went down to work in the Antarctic. Finally, she undertook some work in the eastern Pacific, before returning home through the Panama Canal. These cruises were not without their moments of excitement, such as the attempted arrest off the Falkland Islands by an Argentinian destroyer. Most of the time, however, Shackleton carried out routine work and collected a great deal of valuable material which is being worked on at various centres throughout the country.
The largest single part of Shackleton’s voyage was spent in the western Indian Ocean, where she undertook a number of 20-26 day cruises. This region is one which has been visited in the past by British research vessels, most notably by RRS Discovery in 1963 and 1967. Some of the work planned for Shackleton was to follow up studies made on these two cruises, but the greater part of her work was on the investigation of new problems.
After working with Dr Calvert’s group off SW Africa, Shackleton sailed for the Gulf of Aden, where the first of the Indian Ocean geophysical cruises, that with Dr Girdler’s group, was undertaken. This was followed by geophysical work in the Gulf of Oman, with Dr Matthews’ group, and in the northern Arabian Sea, with Dr Whitmarsh’s