Heard Submarine While Diving?

[smudge13]

I just retired form the Navy in 2014. I was a sonar technician and spent my career tracking submarines. I can tell you that low frequency sound can travel enormous distances underwater. It's though that humpback whales communicate at transoceanic distances.

Diving La Jolla Canyon you can also experience a phenomenon called "upslope enhancement" where the contour of the sea floor will enhance sounds of certain wavelengths as they propagate towards shallower water.

That being said, what you heard with your human ears was not likely a military submarine especially if you're describing it as a high pitched whine. More likely a boat whose noise was trapped in a surface layer propagation path and was therefor well with in hearing range underwater but beyond your visual horizon on the surface. Also, because of the tremendous difference in the speed of sound in water vs the speed of sound in air, your ears are not calibrated to pick out the direction that a sound is coming from in water. You cannot accurately tell which direction a noise is coming from underwater.

 

[flyboy08]

He could tell you, but then he'd have to kill you.

Lol, no....I had dealings with RCA Govt skunk works and GE....got to fly a Soviet Hind Mi24 Heicopter too, but that's another story

 

[Steelyeyes]

I was on a couple of subs. Our sonar techs claimed that some of our newer (back then) boats made less sound than the ocean around them. Having been on two that were actively hunted by a pretty large ASW effort and not found I'd lend some credence to that.

I do know that a Washington State Ferry makes a hell of a racket going by at cruising speed. It's so loud you can feel it from 800 yards away.

The tourist subs like the those they have in Maui, Cozumel, etc. make enough sound you can hear them standing in a boat above them. We got to the Carthaginian wreck just as they were leaving and I knew what that sound was as soon as I heard it.

 

[Killercavecow]

The tourist sub that goes through Saipan harbor is loud as hell. Clicks, whines, banging, you know it's there.

 

[hroark2112]

I was on several nuclear submarines. My last boat was fresh out of new construction. We did sound testing on the boat with another submarine less than 100 yards away, and they could not register us on their sonar, even when we directly shorted motors to the deck and slammed hatches intentionally. The only way they heard us was the underwater phone communication.

 

[Dave Bevan]

I had a rather interesting dive the other day. There was a survey boat towing some sort of array and it was making allsorts of noises. Pulses clicks and pings. Was more than 200m away and it was loud as anything.

 

[JBFG]

I've seen one in Hawaii. We were diving between 2 wrecks in Ohau and there was a submarine that took tourists to see those wrecks. I waived at it as they were waiving at me. We were about 100' deep. you can definitely hear it before you see it.