Commander Brad MacKenzie of the U.S. Navy wages an undersea battle-to-the-death with the enemy sub Sea Devil, the most sophisticated, untrackable secret weapon ever designed. Reissue.
This book is based on the technology of the late 80's with plausible threat assessments from IRA offshoots and Russian sub technology. The Soviet Union was about to disintegrate by the time of publication. The US NR1 is a tracked nuclear sub, that may have been acknowledged and publicized at that time.
The good points of the book are the technology, a fast paced plot that has some remote plausibility, characters that fit the roles provided, and jumping story segments that last long enough to fill out a story without leaving the reader constantly text switching.
Some trivial character build up and activity could be eliminated to drop the page fluffing, but still leave the mainline story intact.