launch transients, torpedo sounds, and realism

[Keelbuster]

Originally Posted by Alain-James

Hum there was nothing such as an active sonar/ranging ping available on a U-Boot, maybe except for a very few number of them who may have been fitted with some active equipment... right?
I guess the presence of such gear in SH3 is somewhat fictionnal (the same with the ingame early availability of the type XXI boats).

But in the eventuality such equipement was available, yes technically speaking a ping would be heard by anyone in range with hydrophones, or even without them.

Yep, but Dangerous Waters/Contemporary sonar assets are omnidirectionnal, while a lot of WW2 hydrophones were often directionnal (aka you have to turn the wheel/the switch to listen in a given direction) (btw please tell me if Im wrong...). I suppose anyway that monitoring primitive omni-directional equipement, such as the first sonoboys, must have been quite a pain in the **s without an electric screen...

I guess I'm just wondering - if you can't detect a launched/running torpedo with passive sonar, what are your chances of detecting a sub set for silent running on passive sonar? In game, if an escort comes close enough to you, it will detect you on passive sonar. However, if you fire an electric torpedo, even right beside an escort, unless the torpedo hits something, it's as if it was never there. I've taken long shots with T2s, and had them drift on through the convoy and out the other side. It's as if nothing happened - the escorts are oblivious to it. In real life I imagine that one of the 8 or 9 escorts would happen to pass his hydrophone over a bearing with a torpedo in it, and would recognize it. If you can't hear a torpedo, how are you going to hear a sub....

[Amiral Crapaud]

Originally Posted by Keelbuster

I guess I'm just wondering - if you can't detect a launched/running torpedo with passive sonar, what are your chances of detecting a sub set for silent running on passive sonar? In game, if an escort comes close enough to you, it will detect you on passive sonar. However, if you fire an electric torpedo, even right beside an escort, unless the torpedo hits something, it's as if it was never there.

That's a good point!

[Subnuts]

Originally Posted by Keelbuster

I'm sure this topic has been beaten to death over the years, but it still bugs me. I'm not sure what the advantage was of an electric torp over a steam torp in real life, because I imagine that a torpedo launch (and it's entire subsequent run) would be such a noisy event that escorts would most certainly hear it, and hence get a good bearing to the attacker from it. Like - in real life, at torpedo launch, I imagine that ships would start evasion right away following a 'Torpedo in the water' report. I wonder if there's some way to mod this into SH3??

During the Second World War, escort sonar could only hear down a narrow cone, normally about ten degrees across. The operator could rotate the sonar apparatus to listen in different directions, but he couldn't listen to the entire ocean at once. This isn't the case now, since modern sonars use hundreds of fixed hydrophones in large arrays, and display screens can depict incoming data in realtime, but in WWII, this limitation was a huge issue.

The main advantage of an electric torpedo is that they didn't leave a foamy wake which basically said "go down the bearing this wake and you'll find me soon enough!"