Escort vessels equipped with ASDIC and hydrophones always had those stations "full up" because contact with U-boats can happen at any moment. Not everybody makes night attacks as the manual says. The limiting factors with the efficiency of passive sonar and active sonar arrays in WWII were primarily hardware-based, you could only generate so much power and transmit it effectively, and you could only amplify sound so much because of the technology limitations of the time.

Flow-noise blankets the sensor and you have to be running below a certain speed to make use of your sonar systems. I haven't seen a convoy with merchantmen running too fast to be unprotected by ASDIC/hydrophone, but I have seen taskforces of RN and USN vessels moving so fast that I should have been able to sprint into a close range firing position, empty my tubes, and dive away without them knowing anything until my targets turned into raging infernos of suck. This was not the case, sadly.

You should be able to hear a torpedo launch (compressed air ejection) even if your sensor is mostly turned away from the launch point, because water doesn't compress and therefore carries sound energy (essentially miniature shockwaves) very well. You won't get a bearing, and you won't get any sort of reasonable range information (hard to estimate from passive plots anyways), and by the time you hear it the launch will have been long since completed and the boat will likely have repositioned itself. But you should be able to hear it.

Small mechanical noises like the torpedo doors opening you should be able to hear when you're monitoring a contact directly and the sonar conditions are favourable.

Sidenote: What depth does the game model the thermocline at? I hear things like 200-250m.

IIRC the game itself doesnt model them, but sh3 commander does make random asdic max depth detection in order to simulate the thermal layers.(if that is what you mean?)

That is what I mean. Thanks! Or Благодарности!, if I remember my very basic Bulgarian correctly. :DL

How nice of you and yes you are correct.

Благодарю more likely :)

It is Благодаря actually but the word he used is just as right, may be not so much in use in daily conversations nowdays.

Yeah, the Bulgarian I know is Yes/No/Thanks/Please/"No, sorry, I'm not interested in invading Romania today" and I'm joking about that last one. It was brought up in Russian class where we were discussing the differences between Tsarist-era Russian and Communist-era Russian, so if my Bulgarian is out of date I wouldn't be surprised.

Would one, when speaking Bulgarian, conjugate the word to match the Slavic "I/We/Them/Us/It/He/She" ending? "I thank you" (Ya "blagadarnostyu") or "We thank you" (Miy "blagadarnostyom") for example, or is it simply that the word has evolved with the language?

Well it is like this about the word thank you (it is hard to translate in such manner)

I thank you - Благодаря ти or (Аз ти благодаря - but that sounds a bit odd and i think is gramaticly incorect)
We thank you - Благодарим ти

thats it for first person.In this case "I" (аз) in the beggining shouldnt be said.
It is a bit hard to explane since this is my native language and i understand it because this is how always was (to my perspective).

Howeever i think we are getting a bit offtopic here :)

<A voice from the distance> Hiiiiijackers! :haha:

Bulsoldier: Not too dissimilar to Russian then. I understand. Thanks.

Contact: Well, at least you didn't say "pirates". I don't want to be shot by the US Navy in the Gulf of Aden in the middle of the night. (Booyeah. Recent events reference +10).

In Real Life how did a usual U-Boat execute its patrol ?

For example, did they submerge every 20km to perform a hydrophone sweep to see what's in the area ? Or did they mainly run on the surface at 2/3rds speed and only submerge when forced to ?

I ask because there are scenes in Das Boot when the U-Boat is toughing it out in a storm when its obviously better to be 60m down in calmer water and where you'd have more chance of detecting something using the Hydrophones than eyes.

Yet in books i've read there is no mention of submerging every 20km to make optimum use of the Hydrophone, the lasting impression is that they only submerged when they had too aside from the daily dives to fine tune the trim.

My ultimate goal is to employ the same patrol procedures as in they did in Real Life (in between contacts) so any help here would be greatly appreciated.

Mucho Cheerso...:hmmm:

Usually u-boats dived if they spoted an aircraft or DD approaching. You can put this to forced dive if you want.

U-boats also used a bad weather to cover themselves from patroling aircrafts and on purpose remained on surface to jump to another area more quickly. But of course if seas were rough, remaining on surface had caused larger fuel consumption. So it was up to captain to decide what to do depending on circumstances.

Thanks for the reply Contact....continuing in the same vein, how many times would they have submerged to perform a Hydrophone sweep of the area during the day ?

I imagine they only dived once a day (the trim dive) and then only when it was necessary, i.e. forced to by plane or very bad weather.

I imagine they only used Hydrosweeps when they were in the vicinity of a possible contact, e.g. another u-boat beacon or radio report of possible contact in area such and such.

But then again, I could simpy be imagining things.

Cheers....

I think it also was due to where the u-boat was patroling. If it was the heavy naval traffic area divings were more often to search for potencial targets. However I'm not sure was it as a rule on how often dive procedures had to be made.

More chances to spot a target was submerged since as you know hydrophones could pick up screw noises from much greater distance then eyes of watch crew did.