The Mark 60 CAPTOR (Encapsulated Torpedo) is the United States' only deep-water anti-submarine naval mine.^[4][3][2] It uses a Mark 46 torpedo^[2][3] contained in an aluminum shell that is anchored to the ocean floor.^[2] The mine can be placed by either aircraft, submarine or surface vessel.^[2][3] The torpedo, once placed, can last anywhere from weeks to months underwater.^[3] The original production contract of the CAPTOR mine was awarded to Goodyear Aerospace in 1972, and entered service in 1979.^[3] It was hoped to reduce minefield costs and used in the creation of a barrier of the "Greenland-Iceland-United Kingdom gap to interrupt Soviet submarines in the event that deterrence failed."^[4]

The mine uses Reliable Acoustic Path (RAP)^[2][1] sound propagation to passively identify and track the difference between hostile submarine signatures, surface vessels and friendly submarines.^[3] Once identified, the torpedo leaves its casing to destroy its target.