How did they detect me?

[mightymightychatham]

Yes, I know there's a million "How did they spot me?" threads, but I read through a heap of them and couldn't find an answer for this situation. I'm sure there's an answer in there somewhere, but help the new kid out, eh?

I came across a seven column convoy in February 1941 guarded by four frigates and a corvette. I've never seen one this big before so I'm rubbing my hands together with glee. My usual tactic for large convoys has been working quite well; get around in front, submerge in a postition which will put me in a position to be amongst the columns when the convoy passes but as far from the path of the escorts as possible. Then when the escorts have passed, pop up the periscope and line up simultaneous shots for front and rear torpedoes, let them loose, dive, evade the angry bees and go my merry way.

This time I misjudged it a bit and one of the frigates passed close by me whilst zagging. I was at 12 metres, silent running, engines off, zero knots. I was not even drifting. Periscope down all the way. Seas were as calm as they come. About 0250, so quite dark. I play with the "stealth bar" on; when it reached about 1000m from my boat (or thereabouts) the stealth bar went yellow-orange-red in about 20-30 seconds. There was no pinging sounds. I was not using time compression. As soon as the stealth meter went red, the frigate changed course and then began pinging me.

Of course, his buddies joined the hunt and I was forced to dive and evade. Eventually I lost them but by the time I was able to resurface, the convoy was close to the continental shelf; I would not be able to catch it in deep water and I didn't fancy trying to lose up to five escorts in shallow water. So the seven column convoy steamed peacefully away into the rising sun as I cursed my luck and continued to my patrol sector.

How did he find me? Some new technology I'm not aware of? Or is there an obligitory minimum detection distance? From memory I've laid doggo that close to a destroyer once before and he just cruised past, albeit in mid-1940.

I use GWX and a few other graphic type mods. Any help would be appreciated!

[Captain Nemo]

As the war progresses escorts become more efficient at detecting you whether submerged or surfaced. Calm seas also improves their ability to detect you. Even though you are running silent there is still a certain amount of noise coming from your boat to enable the escorts to find you. In the situation you describe, personally I would have tried a night surface attack over a submerged approach.

Nemo

[JazzJR]

Originally Posted by Captain Nemo

personally I would have tried a night surface attack over a submerged approach.

Nemo

As long they don't have Radar it is good to try a night attack. But it only works if it is a dark night without a visible moon. I often had, that the Escort spotted me 4000meters away! in a night. And if they light up their beams all ships do the same and you will get be depth charged to the death. I mostly hate these Flower classes. They are really annoying and will destroy your boat to 100% percent chance. I also used silent running and a lot of different stuff to avoid them, but is almost useless in 1941 and upwards.

[Jimbuna]

Try never to leave your cross section side on to the escort, better to be pointed at them.

You may also have come across one of the elite crew status boats which does make them somewhat efficient...even though you were in 1941 there are some scripted in.

[Captain Nemo]

Originally Posted by JazzJR

As long they don't have Radar it is good to try a night attack. But it only works if it is a dark night without a visible moon. I often had, that the Escort spotted me 4000meters away! in a night. And if they light up their beams all ships do the same and you will get be depth charged to the death. I mostly hate these Flower classes. They are really annoying and will destroy your boat to 100% percent chance. I also used silent running and a lot of different stuff to avoid them, but is almost useless in 1941 and upwards.

I have a mod installed that takes away the search beams from merchant ships, which is how I understand it was in real life. This makes moving inside the convoy lanes a little bit easier, but as you point out, once the escorts have radar it is a much more difficult task.

Nemo

[mightymightychatham]

Thanks all for the advice.

Originally Posted by Captain Nemo

Even though you are running silent there is still a certain amount of noise coming from your boat to enable the escorts to find you.
Nemo

Thought it might be something like this. That would be the RL answer anyway, but I wondered whether the game behaved that way as well. Handy to know as I will be ditching the "stealth bar" soon to see how I fare.

Thanks again.

[Fish In The Water]

Originally Posted by mightymightychatham

I play with the "stealth bar" on; when it reached about 1000m from my boat (or thereabouts) the stealth bar went yellow-orange-red in about 20-30 seconds. There was no pinging sounds. I was not using time compression. As soon as the stealth meter went red, the frigate changed course and then began pinging me.

Just so you know, when the stealth bar lights up like a christmas tree, it's an indication that you're in danger of being spotted. Not that you necessarily have been. Hence the pinging after the bar went red.

[JazzJR]

Originally Posted by Fish In The Water

Just so you know, when the stealth bar lights up like a christmas tree, it's an indication that you're in danger of being spotted. Not that you necessarily have been. Hence the pinging after the bar went red.

Well if the bar stays red for more then one second it is too late and the hunt is opened!

[mightymightychatham]

Originally Posted by Fish In The Water

Just so you know, when the stealth bar lights up like a christmas tree, it's an indication that you're in danger of being spotted. Not that you necessarily have been. Hence the pinging after the bar went red.

Right. Didn't know that. I thought once it changed from green, I had been noticed, and the severity of the colour indicated how strong/accurate their reading was. As in; yellow - they know the general area/direction you are from them, red - they know more or less exactly where you are.

Rather, it's "potential" to be spotted. It all makes more sense now. Thanks all for the help!

[yubba]

[mightymightychatham]

I did actually, but since my crew are not a bunch of loveable misfits who somehow are able to work together to defeat a crack squad of a-holes who are using far better equipment, I counted it out.

Plus I never smelled nuthin.

[JazzJR]

and this to escape

[Fish In The Water]

Originally Posted by mightymightychatham

Rather, it's "potential" to be spotted. It all makes more sense now. Thanks all for the help!

You're welcome and good hunting!

[GoDeep]

I don't know how often I have asked myself that question "How did they detect me?" Sometimes it is inexplicable to me, but then again, I am not an expert in the game dynamics.

Often though, it is my own fault. I made too much noise (not saying you did), I stayed on the surface too long, I kept my scope up too long, I raised my scope when I was going too fast...

In your particular situation, could it have been that the top of your conning tower broke the surface? Because you were going dead slow or even at full stop, the boat has a slight positive buoyancy, causing it to run a bit shallower than ordered. If the escort saw your conning tower or any of the equipment on top of it, you'd be found of course. I think this behaviour was added in GWX?

[mightymightychatham]

Originally Posted by GoDeep

In your particular situation, could it have been that the top of your conning tower broke the surface? Because you were going dead slow or even at full stop, the boat has a slight positive buoyancy, causing it to run a bit shallower than ordered.

No, I checked my depth as soon as the stealth bar changed. And seas were flat so I can't have been "bobbing up" in the troughs. I think it was probably, as suggested, a combination of me being too close to start with and an elite crew.