technical research ship

Technical research ships were used by the U.S. Navy during the 1960s to gather intelligence by monitoring the electronic communications of nations in various parts of the world. At the time these ships were active, the mission of the ships was covert and discussion of the true mission was prohibited ("classified information"). The mission of the ships was publicly given as conducting research into atmospheric and communications phenomena. However, the true mission was more or less an open secret and the ships were commonly referred to as "spy ships".
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