[John Rogers]

The Russian and Chinese subs are noisy, even if running on batteries as their electric motors are not quiet. Their reactors are noisy even though the Russians tried pressurized water systems with natural circulation which had issues with the water cavitating at speeds over 2 or 3 knots!

Back in 1978 I was on the CGN25, USS Bainbridge, over in Hawaii with "war games" with Japanese, Australian, and Singapore Navies. Sooooooo we loaded up a test ASROC to show all those guys how to "kill" a submarine. There were 9 of us "good guys" going to get the "bad guys" on the boat. So we all sailed around for about 4 hours in the box are that the sub was supposed to be in, no luck at all by any of us! So after time ran out the sub surfaced about 1/2 mile away and actually flashed the signal lamp to us of all things. They started to dive and we ran the ASROC torpedo out on the forward launcher and a count down started and boom away the ASROC went. About the time the missile left the rail that sub went to silent running. Down goes the ASROC at what looked like right on top where the sub had been, but noooooo they weren't there. The ASROC looked around like they really do and guess what, even though we were doing only 5 knots our screws made so much noise that thing ran right under our stern!!!! If it had been live....KABOOM for us. Those were older boats too.
John