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.