Sorry for the loss of your friend Bic!
The SOSUS system was active in the late 50's and manned by Sonar Techs. In 1969, a small group of ST's were asked to volunteer for a classified rating, Ocean Systems Tech (OT). Sonar guys were the foundation but the differences in how the data was collected prompted a new job classification. Those of us in early to mid 70's went to the same Sonar School facility in Key West. A pretty nice first duty! In late 76, they move the school to Norfolk Naval Shipyard. There were OT's aboard some ships but it was pretty limited to the TASS ships that FBG mentioned. Most of us, including a old mate of mine from Iceland spent their entire Naval careers and never set foot aboard a "floaty thing"! My friend has 34 years, retired as a Captain and he has no sea time at all...