Wartime hydrophone ranges?

[treblesum81]

Can anyone point me to information about the actual reception ranges for hydrophones during the war?

Thanks

[tomoose]

http://www.fleetsubmarine.com/sonar.html
Mentions U-boats being able to 'hear' up to 50 miles by end of war.

http://www.ibiblio.org/hyperwar/USN/rep/ASW-51/ASW-PART-I.html
more of a history of anti-sub warfare during the war.

http://www.uboataces.com/hydrophones.shtml
This one states U-boat detection ranges as 20km for vessels and up to 100km for convoys.

[treblesum81]

Early war German hydrophones could detect a convoy over 50nm away? I wonder if that applies to US hydrophones as well? Or were the Americans far behind in sub technology at this point in the war?

[tomoose]

They weren't that good at the beginning of the war. I don't think you can rely on specific ranges anyway as there were many variables that affected hydrophones/sonar such as depth, temperature, the weather topside etc.

So while you could state "my hydrophone's range is 25 miles" you wouldn't want to hang your hat on that. You'd have to be fairly flexible on range estimates for passive stuff. Having said that I'm sure a really good experienced hydrophone operator would be able to accurately 'guess' a range.

[Rockin Robbins]

Well, the US subs had two things that the Germans didn't: active sonar and ultrasonic sonar. Both were vitally important to making the US sub more deadly.

Sonar range is also incredibly dependent on local listening conditions. The same sonar good for 50 miles one day won't be good for 200 yards the next.

I don't know if any direct comparisons between US and German WWII sonar capabilities exist, but I would predict no clear winner, with each better in some categories and worse in others.

[treblesum81]

What I'm trying to get at is whether or not the 15000m max range applied to US hydrophones is at all accurate. Because conditions vary greatly due to surface weather etc., if 15000m is a starting point and then its degraded from there, I'm wondering if this is putting an overly heavy handed limitation on hydrophone detection range?

I guess the best question to ask is whether or not the game simulates hydrophone range degradation in poor weather conditions or not?

[Rockin Robbins]

Well it certainly does for enemy escorts. In TMO if you attack in daylight smooth water you're just serving them dinner. But if you have a nice rough surface it's amazing what you can do!

Since I do very little long-range sonar searching and rely on my radar and 9 knot speed to find targets much more efficiently, I can't really answer your question about sub sonar.