local-area underwater navigation system

local-area underwater navigation system

[′lō·kəl ¦er·ē·ə ¦ən·dər¦wȯd·ər ‚nav·ə′gā·shən ‚sis·təm] (navigation) A system applied chiefly in the inspection and maintenance of offshore structures, in which time differences between the reception of acoustic signals from a chain of transmitters are used to determine the positions of divers and of crewed and uncrewed underwater vehicles. Abbreviated LAUNS.