How do they know where I am?

9emini · 03-05-12, 05:23 PM

I'm 90m under the surface of the Strait of Gibraltar on 13/3/1940. I'm being pursued by 4 vessels who thankfully have exhausted their supply of depth charges. Battery level < 12.5%. I've made a course change since last exceeding 75rpm and am not being pinged. How do my pursuers know where I am? It's almost 1700 hrs - can they see me or something? In a VIIB... please help!

VonApist · 03-05-12, 05:28 PM

Probably, you are too shallow. You need to dive below 150-200m for the thermal layers to protect you. Speed 1 knot silent running, keep helm at 5 degrees to port

Gargamel · 03-05-12, 06:00 PM

Afaik thermal layers are not modeled in sh3. But the action is still good. Dive deeper.

But it's a small place, not many places you can be going there. They're probably guessing well.

krashkart · 03-05-12, 06:05 PM

As above, and keep moving away. Destroyers will hunt around for awhile after they've expended their DC's. Seems to take an eternity, but eventually they get bored and leave.

Your battery charge is pretty low. Stay deep and maintain those low revs as long as batteries permit, then get up above 100m when they drain down to critical level. If your batteries peeter out below 100m depth you have no way to maintain depth, and stand a good chance of sinking below your crush depth. So keep an eye on it.

If all else fails, scuttle the boat and start a new career.

(Come to think of it, in all my experience below the 110m mark I had to maintain 2 knots to keep the boat from sinking. Use your best judgement.)

EDIT: OTOH if you're sure they've dumped every last ashcan on you, you could just cut engines at shallow depth and see what happens. Stay still and the buggers might just give up anyway, and you'll still have some battery charge left. *shrug*

Quote:

Originally Posted by Gargamel

Afaik thermal layers are not modeled in sh3.

That's what I remember reading around here somewhere. I have noticed that I could get away with higher revolutions at deeper depths (or so it seemed), but if I went too high they would detect me. I'll have to try again one of these days, after the skeeters have caught my scent. It's probably just wishful thinking.

Raticon · 03-05-12, 07:11 PM

IIRC SH3 Commander mimics thermal layer-effects on detection equipment. I decided to look it up and found this in the manual:

Quote:

Originally Posted by SH3Cmdr Manual

Simulated thermal layers - by Hemisent.
Randomly adjusts active/passive listening device values to simulate the impact of thermal layers. Editable through 'Randomised events.cfg' located in your SH3 Commander\Cfg folder.

Unsure if it gives you any help at 90m though. But as some people have posted in other threads concerning thermal layers and detectability it greatly helps to dive deep and just run real quiet.

Why the 5-degree rudder adjustment btw? I always thought hard 35-degree knuckles from time to time, altering your course significantly in an erratic way would confuse anyone that's looking for you. All at "Schleichfahrt" of course.

9emini · 03-05-12, 07:17 PM

Wow thanks for all the advice. Is it safe to spend time below 100m in a boat that's been damaged (and then repaired)? Oh yeah - silent running. There's a good idea! I usually only bother to maintain sub-75rpm speeds without also running silent. Might explain some other odd detection behaviour I've noticed...

krashkart · 03-05-12, 07:48 PM

Quote:

Originally Posted by 9emini

Is it safe to spend time below 100m in a boat that's been damaged (and then repaired)? Oh yeah - silent running. There's a good idea! I usually only bother to maintain sub-75rpm speeds without also running silent. Might explain some other odd detection behaviour I've noticed...

Just make sure you have any flooding under control and you should be good to go for the dive. Not sure that hull damage will increase the likelihood of an implosion when you go deep... but I could be wrong. Never gave me any trouble that I remember, anyway.

Silent running does seem to help your stealth. In some cases your throttles will go automatically to Ahead 1/3 when you order silence, so keep an eye out for that just in case and re-adjust your speed as necessary to keep the props quiet.

Quote:

Wow thanks for all the advice.

That's what we're here for.

9emini · 03-05-12, 07:55 PM

Yep silent running AND <75rpm was the key - I'm leaving the four behind. Now to haul my 62kt booty back to Kiel!

Raticon · 03-05-12, 07:55 PM

Silent running also stops all activities on the boat that makes noises, so when running on "Silent running"-mode, no flooding will be pumped away from flooding compartments in the U-boat, no torpedo-reloading is taking place, no repairs and no schnorkelling. All these activities were more or less noisy and i have experienced enemy DD's having an easy time finding me if they have caused flooding in some compartment for me. A couple of pumps running like crazy to eject all the flooding water must have made a lot of ruckus i think...

I have caught myself forgetting to "shut off" silent running sometimes, even after i have gotten rid of the enemies following me and i have surfaced and steamed away. "Enemy merchant spotted!" - SWEET!... But alas, i forgot to switch to "normal propulsion" and so, no torpedoes have been loaded on the entire day! Yet still the crew in the torpedo-room are utterly exhausted even though they haven't loaded any torpedoes. Guess the thought of reloading 4 torpedoes is enough to make you almost faint of exhaustion eh?

Pisces · 03-05-12, 08:20 PM

Quote:

Originally Posted by Raticon

...

Why the 5-degree rudder adjustment btw? I always thought hard 35-degree knuckles from time to time, altering your course significantly in an erratic way would confuse anyone that's looking for you. All at "Schleichfahrt" of course.

Have you noticed how your speed drops when you make those 35 degree turns. 75 rpm is allready really slow. The last thing you want to do when being prosecuted by destroyers is staying in the same place. So making gentle turns keeps your speed up and still alow you to change course to be somewhere else at their next attack run.

Gargamel · 03-05-12, 08:59 PM

Not being in silent running is how they are tracking you.

Hinrich Schwab · 03-05-12, 09:14 PM

Quote:

Originally Posted by 9emini

I'm 90m under the surface of the Strait of Gibraltar on 13/3/1940. I'm being pursued by 4 vessels who thankfully have exhausted their supply of depth charges. Battery level < 12.5%. I've made a course change since last exceeding 75rpm and am not being pinged. How do my pursuers know where I am? It's almost 1700 hrs - can they see me or something? In a VIIB... please help!

Looking at your battery charge, they are almost exhausted. Silent speed is all you will be able to do with such depletion. Also, you must be below the thermal layer to really lose escorts. 150 meters is a good reference. Depending how much more of the strait you have to traverse, you may be forced to surface due to battery exhaustion. If you can wait until after dark, that may help if you must surface. With such low batteries, even if all goes well, a successful crossing will be challenging.

VonApist · 03-06-12, 03:25 AM

Quote:

Originally Posted by Raticon

IIRC SH3 Commander mimics thermal layer-effects on detection equipment. I decided to look it up and found this in the manual:

Unsure if it gives you any help at 90m though. But as some people have posted in other threads concerning thermal layers and detectability it greatly helps to dive deep and just run real quiet.

Why the 5-degree rudder adjustment btw? I always thought hard 35-degree knuckles from time to time, altering your course significantly in an erratic way would confuse anyone that's looking for you. All at "Schleichfahrt" of course.

At 35 degrees your turn/speed ratio is bad. At 5 degrees you gently turn, keeping your speed, being silent and quietly alter course without problems. Hard turns and increase of speed only for 1-2 minutes after being depth charged, and that is only if you are hunted by 1 destroyer. If its 2 or more wont help much, unless its last resort, if you feel that the depth charges are coming right on you.

My view anyways
Best

Harald_Lange · 03-06-12, 03:46 AM

Personally I would have blown ballast, ahead flank and manned the deck guns and flak guns and given them everything I had

On second thoughts, I suppose the object of the game is to achieve more than one patrol...

VonApist · 03-06-12, 04:12 AM

Quote:

Originally Posted by Harald_Lange

Personally I would have blown ballast, ahead flank and manned the deck guns and flak guns and given them everything I had

On second thoughts, I suppose the object of the game is to achieve more than one patrol...

Being so confident re a surface stand off I can only assume that you have converted the Bismarck into a U-Boat

Just kidding

03-05-12, 05:23 PM	#1
9emini Seaman Join Date: Jan 2009 Location: Aboard the Galaga Posts: 37 Downloads: 1 Uploads: 0	How do they know where I am? I'm 90m under the surface of the Strait of Gibraltar on 13/3/1940. I'm being pursued by 4 vessels who thankfully have exhausted their supply of depth charges. Battery level < 12.5%. I've made a course change since last exceeding 75rpm and am not being pinged. How do my pursuers know where I am? It's almost 1700 hrs - can they see me or something? In a VIIB... please help! __________________ SH3 + GWX3.0 + 100% realism + restart patrol if sunk + no TC =

03-05-12, 05:28 PM	#2
VonApist Navy Dude Join Date: Mar 2011 Location: Greece Posts: 175 Downloads: 6 Uploads: 0	Probably, you are too shallow. You need to dive below 150-200m for the thermal layers to protect you. Speed 1 knot silent running, keep helm at 5 degrees to port __________________ "Submariners are a special brotherhood, either all come to the surface or no one does. On a submarine, the phrase all for one and one for all is not just a slogan, but reality.” -- VADM Rudolf Golosov

03-05-12, 06:00 PM	#3
Gargamel Lucky Sailor Join Date: Oct 2010 Location: Rome Posts: 4,273 Downloads: 81 Uploads: 0	Afaik thermal layers are not modeled in sh3. But the action is still good. Dive deeper. But it's a small place, not many places you can be going there. They're probably guessing well. __________________ Luck is a residue of Design.

03-05-12, 07:17 PM	#6
9emini Seaman Join Date: Jan 2009 Location: Aboard the Galaga Posts: 37 Downloads: 1 Uploads: 0	Wow thanks for all the advice. Is it safe to spend time below 100m in a boat that's been damaged (and then repaired)? Oh yeah - silent running. There's a good idea! I usually only bother to maintain sub-75rpm speeds without also running silent. Might explain some other odd detection behaviour I've noticed... __________________ SH3 + GWX3.0 + 100% realism + restart patrol if sunk + no TC =

03-05-12, 07:55 PM	#8
9emini Seaman Join Date: Jan 2009 Location: Aboard the Galaga Posts: 37 Downloads: 1 Uploads: 0	Yep silent running AND <75rpm was the key - I'm leaving the four behind. Now to haul my 62kt booty back to Kiel! __________________ SH3 + GWX3.0 + 100% realism + restart patrol if sunk + no TC =

03-05-12, 07:55 PM	#9
Raticon Seaman Join Date: Oct 2010 Location: The Arctic Posts: 38 Downloads: 4 Uploads: 0	Silent running also stops all activities on the boat that makes noises, so when running on "Silent running"-mode, no flooding will be pumped away from flooding compartments in the U-boat, no torpedo-reloading is taking place, no repairs and no schnorkelling. All these activities were more or less noisy and i have experienced enemy DD's having an easy time finding me if they have caused flooding in some compartment for me. A couple of pumps running like crazy to eject all the flooding water must have made a lot of ruckus i think... I have caught myself forgetting to "shut off" silent running sometimes, even after i have gotten rid of the enemies following me and i have surfaced and steamed away. "Enemy merchant spotted!" - SWEET!... But alas, i forgot to switch to "normal propulsion" and so, no torpedoes have been loaded on the entire day! Yet still the crew in the torpedo-room are utterly exhausted even though they haven't loaded any torpedoes. Guess the thought of reloading 4 torpedoes is enough to make you almost faint of exhaustion eh? __________________ Ping.........Ping......Ping....Ping...Ping..Ping.P ingPingPing KABOOM!

03-05-12, 08:59 PM	#11
Gargamel Lucky Sailor Join Date: Oct 2010 Location: Rome Posts: 4,273 Downloads: 81 Uploads: 0	Not being in silent running is how they are tracking you. __________________ Luck is a residue of Design.

03-06-12, 03:46 AM	#14
Harald_Lange Ensign Join Date: Jan 2012 Location: NY Harbour, Periscope depth. Posts: 235 Downloads: 160 Uploads: 0	Personally I would have blown ballast, ahead flank and manned the deck guns and flak guns and given them everything I had On second thoughts, I suppose the object of the game is to achieve more than one patrol...