Yes, thanks. I'd expect something for any routine dive too, like on US boats. It's a fine point I have to say I am not sure what the historical answer is. I must find out!

Just re-installing this after reading through your thread.!
I think it's worth it. When this game released it got a knock as the Sims in subs, but since then the game has taken a slightly different course, and has become more like the other sort of 'sim'. I really like it so far. I've dropped about 30 hours in to it already. There are a few things I don't like or wish to be added or altered, but overall I'm impressed with UBOAT and am having a good time with it.
I talked about how cool it is to have other submarines out there with you. These boats can also send beacon signals, which was the primary method of course that U-Boats used to gather. It works beautifully, homing me in. And now we have two boats working over the convoy, splitting the defenses. No sweeter sound than distant depth charging. The AI boats seem to prioritize escorts too, or maybe it's just worked out that way. In one convoy attack in the North Sea, all that survived were one merchant ship and a lonely corvette, and no warships were sunk by my boat in this encounter. Having AI boats adds so much. Silent Hunter should definitely have this. But we've known this forever.
I am using relaxed targeting, allowing crew members to calculate the solution. But I've fallen in to sort of a hybrid approach. The only difficult thing in torpedo attacks, when having map contacts on, is determining speed. Angle on the bow is easy, and range is too, using the map tools. I have no nomograph in the game here, which is what I use in SH to find the target's speed. The crew are very useful for working out the speed.
Targeting data can be entered manually in the UZO or attack scope screen. Works perfectly as long as I know -- or guess right -- the speed. In convoy attacks this is nice since it speeds everything up, rather than waiting for the crew to do it. It also allows me to be more effective at night. Visual range is short at night, and if a player is not using the 'darker nights' setting, he can see a lot farther than the crew, who are considered to be using the darker nights, reducing their view range so much that surface or periscope attacks at night become very difficult, due to how close you need to be to the target to calculate the solution automatically. I think I'll print out a nomograph.
I was going to comment on the awards system. In my first career I won the Knight's Cross with Oak Leaves too quickly, as I thought and was awarded before the Knight's Cross, which was skipped over. I started a new career when working out achievements, and this time around it has been better paced. I had done Scapa Flow in the first career, and that battleship must have been worth a lot. Because in this new career the Knights Cross was awarded at about the right time, with around 100,000 tons sunk. 200,000 was the threshold for Oak Leaves during the war. I don't see anywhere that the game is keeping a running total of my tonnage, but adding up each patrol so far it is close to 100k, probably a little over. Playing with 'semi-realistic' torpedo reliability means the fish rarely fail, so big bags are easier to get, and my best patrol so far is 43,000, not including warships, which are not tallied for whatever reason, but probably factor in to the awards system.
Aircraft are no joke, as it should be. Planes should be the biggest threat to survival in a U-Boat game. Tempting fate I have yet to be sunk (61% difficulty) but aircraft have been close to pulling it off. It feels really good, and they will get me one of these days.
Destroyers and corvettes I'm still working out. My last patrol in the North Sea (April 1940) I did a couple convoy attacks. Reaching attack position and firing torpedoes has been straightforward. But once the the warships are alerted by the hits they come looking. They found me and hunted pretty relentlessly, for about three hours. I kept feeling like I had given them the slip, but they managed to reacquire my boat. Not that deep here so it was nailbiting and I loved it. Having sound bearings on the map (and improved hydrophones with all-around coverage) allows me to react in real-time, keeping my silhouette narrow. Without this I maybe would have been sunk. I have the AI set to medium difficulty at the moment.
I took a mining mission, which is maybe the first time I've ever laid mines in a sub game? Can't recall it, maybe in SH2 or something? The location was off the island of Portland in the Channel. It all went well, never even saw a warship until I had left the channel. I wonder if those mines can sink a ship later in the career, and if I would get notification?
I've taken some screens which I forgot to attach before leaving for work, and I'll add some more later.
Full release on Friday