Strange Behaviour
 

Alright, so I thought I might have some fun with some neutral merchants by sneaking my boat under their keel and hopefully catching the shot on free-cam. So I dived to 25 meters, retracted all my periscopes and watched...

Here's when the strange thing happened, as the U-boat was about to go under the ship's keel, I see the merchant stopping and backing away! What gives? A surface scan showed no German aircraft in the vicinity nor any AI U-boats...

Here's my theory, since I'm playing GWX, the UMark indicator (little orange icon above the sub) was removed by the mod. However, I had downloaded and enabled Venatore's UMark mod shortly after. Could the merchants have somehow seen the indicator on floating on the surface and the game's sensors interpreted this as part of my U-boat, and therefore causing them to back away?

I don't think the AI's sensors should ever detect the U-Mark symbol whether original, modded or removed. :hmmm:

That's what I thought too. But you see, in stock SH3, the UMark stays on the surface no matter what depth the U-boat is at. However, now whenever the boat goes below 90m or so, the icon simply disappears... it reappears again after the sub rises to about 30m.:hmmm:

I think it only dissappears if you press CTRL+Num_Period or have a diving/surfacing angle great enough to rotate it under the water.

That's right, they can't.

What I think has happened here is the boats have detected you in some way (not sure without a video sequence) and have gone into 'anti collision' mode.

Offtopic: Anti collision mode? I thought ships wanted to ram uboats.
I read somewhere that there was some kind of reward if a merchant ship sank a uboat.

Ramming a uboat would have been an act of war, or interperted as such, so a neutral ship would try to avoid that I should think. On top of that he said it was a merchant ship and those were considerably thiner skined than the war ships that were biult for raming to some degree. If a merchant ramed a u boat it was likely that the ensuing damage would have killed both ships and that just wouldn't do. At least that is how I understand things.

The game probly "cheeted" and senced your u boat in some way other than realistic sensors and moved to avoid you just like it would any other object in the game. Perhaps the ship interpeted you as land or a sinking ship or some thing like that; I have seen merchants back up during convoy attacks to avoid raming into a sinking hull that I torpidod

Nope...not in SH3 I'm afraid :nope:

Here's something that happened to me a few patrols ago. It's late 1944 and I came across a lone, slow-moving C2 Cargo ship north of Ireland. I was at 25 m depth and decided to speed ahead of him for a torpedo attack.

Instantly my little detection symbol in form of a U-Boot (I'm playing SH3 1.4b) goes from green to red - the merchant had detected me apparently. I was like "Huh?"

Just to be sure, I checked with my hydrophone man and consulted my map (F5). No warships in the vicinity. So how did this merchant detect me when I went to full underwater speed!? A game bug? :hmmm:

Do late war merchants have hydrophones?
I don't know myself. Just an idea.

Your noise meter is simply an indication you are making noise. It is not an indicator of you being detected or otherwise.

Late war merchants are not fitted with hydrophones. Remember, hydrophones are useless on the surface.

Nor do thay have Asdic fitted.

well in a ramming match between a 6000 ton cargo ship and a considerably smaller u boat, i think there's no question who would come out victorious.

i think i read something that says merchants may try to ram you in the sh3 manual, actually.

Hu, that is intresting. I figured they didn't biuld them for that kind of action and they would likely spring a leek like the Titanic or some thing. But now that I think about it I guess they would have to biuld them strong enuf to take some form of navigational colitions and given the size diferental between soem of the larger ships and the u boat it could work out.

Merchants were not designed or built for ramming (unlike icebreakers) but the sheer mass of a vessel when compared to that of a U-boat is huge.

Both vessels would receive an element of damage (escorts have been known to be totally disabled after such an action) but I'm in noe doubt the U-boat would come of far worse.

Remember, once the pressure hull of a U-boat is torn/holed, it is no longer capable of submerging.

Once, when attacking a convoy, a merchant almost rammed me. It would have succeeded if it wasn't for the fact that I spotted it by pure luck and dived the hell out of its path. I don't know whether it had been intentional, but he sure didn't make any attempts to avoid me.
I posted about it in a novel-like boring thread I opened long time ago.
BTW... Hello again fellow Kaleuns!