Silent running, Stealth vs Detection

Shadowblade · 05-05-09, 02:59 PM

Hi,

I am on harbour raid mission, target location: Southend, Oct 28, 1939. When I am approaching to Southend, my VIIB is always detected by patrolling ASW trawler and bombed with its ash cans. VIIB is submerged and speed is decreased to slow before entering range of enemy's hydrophones. VIIB was detected when moving submerged with speed of 2 knots (default slow speed), course: NW, so I've decreased speed to 1 knot, course: W (greater distance from patrolling ship) and made new test. No change - I was detected again. ASW trawler always changed its course from its patrol trace on south-west, turned to my position on north-east and started its bombing run, so I was forced to start evasive maneuvres.

Is silent running too loud here? What is causing my detection ?

Secondary question: when is speed 2 knots safe and when is needed to cut speed to 1 knot ?

My SH3 is GWX 2.1, during approaching I was also using time compression (speed 1-2 knots takes pretty much time)

Paul Riley · 05-05-09, 03:23 PM

I don't use GWX (at the moment that is) and i'm not sure exactly what tweaks are in it and how powerful them tweaks are,but from various sources I have read,about the conductivity of certain bodies of water in the world,affects how good electrical equipment like ASDIC would work.I may be wrong,but if salt water INCREASES conductivity and the seas around Britain typically the North Sea are high in salt content,this may explain their higher performance when detecting you?

Again,I am not sure if GWX etc implements different types of water,and differing water levels/layers.

And lastly,tactically speaking,you could present the smallest silhouette of your UBoat towards or away from the pursuer,as just when on the surface you are harder to spot face on/away,the same goes for ASDIC,it is harder to detect submerged objects that are face on/away.If your broadside is viewable by his ASDIC that may explain why you are constantly being aqquired.I always try to face him bow first (if he is persistent) and run under him,fooling him hopefully as his DC run will fall away from me as I am going in the opposite direction,then as the DCs detonate you have a few seconds to increase speed as he goes deaf momentarily.If you keep managing to creep away in this way you might get enough distance to increase speed a little,and finally break away.

This is in the stock game mind you,and GWX settings are going to be a lot more stricter

Coyote88 · 05-05-09, 03:41 PM

Are you getting pinged? Running slowly won't protect you against ASDIC detection; it's only a defense against passive (hydrophone) listening devices. If you are getting pinged, then it may be that you're getting too close and/or presenting too large a silhouette.

Shadowblade · 05-05-09, 04:05 PM

Quote:

Originally Posted by Coyote88

Are you getting pinged?

no, this ASW trawler isn't equiped with ASDIC

Pisces · 05-05-09, 04:24 PM

never mind, I was talking gibberish

sharkbit · 05-06-09, 09:18 AM

How deep is the water?
I'll bet he's hearing you because it is pretty shallow where you're at. I'd try to go as deep as the bottom allows you.
Or just give up harbor raiding.

Plus, it's been my experience that ASW Trawlers are in actuality ASW GODS that are all seeing, very persistent, very good at what they do, and very dangerous!

mookiemookie · 05-06-09, 10:14 AM

Go to the 3D view of your conning tower and set the telegraphs on your engines to no more than 100 rpms. That is true silent running speed.

And what sharkbit said....I've found that those stupid little trawlers are damn good at finding you.

Jimbuna · 05-06-09, 12:49 PM

If your harbour raiding, the chances are that you are in very shallow water (10-25 metres on average). How can you expect an ASW not to detect you? Even at silent running it is odds on you will be detected.

Try the Scneider cloaking device

Shadowblade · 05-08-09, 10:50 AM

yes, I was in shallow waters, but I didnt know that I am automatically detected by ASW ships there, because that ASW trawler was far from my sub so I've thought that I was quite safe from the enemy hydrophones...

Was it acoustic or visual (automatic) detection ? What about night harbour raiding, are my chances to be stealthy better in night ?

How deep sea needs sub to be really stealthy in silent runnning mode ? I understand - no shallow waters , but what about open sea ?

Jaman · 05-08-09, 11:16 AM

GWX manual has a secction at the end of it about harbor attacks, but i think this line sums it all pretty well

"The GWX Team recommends players stay out of enemy harbors"

05-05-09, 02:59 PM	#1
Shadowblade Seasoned Skipper Join Date: Jul 2008 Posts: 691 Downloads: 13 Uploads: 0	Silent running, Stealth vs Detection Hi, I am on harbour raid mission, target location: Southend, Oct 28, 1939. When I am approaching to Southend, my VIIB is always detected by patrolling ASW trawler and bombed with its ash cans. VIIB is submerged and speed is decreased to slow before entering range of enemy's hydrophones. VIIB was detected when moving submerged with speed of 2 knots (default slow speed), course: NW, so I've decreased speed to 1 knot, course: W (greater distance from patrolling ship) and made new test. No change - I was detected again. ASW trawler always changed its course from its patrol trace on south-west, turned to my position on north-east and started its bombing run, so I was forced to start evasive maneuvres. Is silent running too loud here? What is causing my detection ? Secondary question: when is speed 2 knots safe and when is needed to cut speed to 1 knot ? My SH3 is GWX 2.1, during approaching I was also using time compression (speed 1-2 knots takes pretty much time) __________________ Kapitänleutnant Vlad von Carstein - U-Flotilla Saltzwedel - U-123, Type IXB SH3 GWX 3.0

05-05-09, 03:23 PM	#2
Paul Riley Ocean Warrior Join Date: Aug 2008 Location: Sheffield, England Posts: 2,679 Downloads: 165 Uploads: 0	I don't use GWX (at the moment that is) and i'm not sure exactly what tweaks are in it and how powerful them tweaks are,but from various sources I have read,about the conductivity of certain bodies of water in the world,affects how good electrical equipment like ASDIC would work.I may be wrong,but if salt water INCREASES conductivity and the seas around Britain typically the North Sea are high in salt content,this may explain their higher performance when detecting you? Again,I am not sure if GWX etc implements different types of water,and differing water levels/layers. And lastly,tactically speaking,you could present the smallest silhouette of your UBoat towards or away from the pursuer,as just when on the surface you are harder to spot face on/away,the same goes for ASDIC,it is harder to detect submerged objects that are face on/away.If your broadside is viewable by his ASDIC that may explain why you are constantly being aqquired.I always try to face him bow first (if he is persistent) and run under him,fooling him hopefully as his DC run will fall away from me as I am going in the opposite direction,then as the DCs detonate you have a few seconds to increase speed as he goes deaf momentarily.If you keep managing to creep away in this way you might get enough distance to increase speed a little,and finally break away. This is in the stock game mind you,and GWX settings are going to be a lot more stricter __________________ Best Patrol: 10 merchants + HMS Nelson for 68.056 Tonnes Last edited by Paul Riley; 05-05-09 at 03:54 PM.

05-05-09, 04:24 PM	#5
Pisces Silent Hunter Join Date: Dec 2004 Location: AN9771 Posts: 4,904 Downloads: 304 Uploads: 0	never mind, I was talking gibberish __________________ My site downloads: https://ricojansen.nl/downloads

05-06-09, 09:18 AM	#6
sharkbit The Old Man Join Date: Apr 2008 Location: Denver, CO Posts: 1,529 Downloads: 334 Uploads: 0	How deep is the water? I'll bet he's hearing you because it is pretty shallow where you're at. I'd try to go as deep as the bottom allows you. Or just give up harbor raiding. Plus, it's been my experience that ASW Trawlers are in actuality ASW GODS that are all seeing, very persistent, very good at what they do, and very dangerous! __________________ “Prejudice is blind. There will always be someone who says you aren’t welcome at the table. Stop apologizing for who you are and using all your energy trying to change their minds. Yes, you will lose friends, maybe even family. But you will gain your self-respect. You will know your worth. Once you have that, nothing can stop you.”

05-06-09, 10:14 AM	#7
mookiemookie Navy Seal Join Date: Nov 2005 Location: Houston, TX Posts: 9,404 Downloads: 105 Uploads: 1	Go to the 3D view of your conning tower and set the telegraphs on your engines to no more than 100 rpms. That is true silent running speed. And what sharkbit said....I've found that those stupid little trawlers are damn good at finding you. __________________ They don’t think it be like it is, but it do. Want more U-boat Kaleun portraits for your SH3 Commander Profiles? Download the SH3 Commander Portrait Pack here.

05-05-09, 03:41 PM	#3
Coyote88 Seaman Join Date: Jun 2008 Location: Cruising the Norwegian coastline Posts: 39 Downloads: 7 Uploads: 0	Are you getting pinged? Running slowly won't protect you against ASDIC detection; it's only a defense against passive (hydrophone) listening devices. If you are getting pinged, then it may be that you're getting too close and/or presenting too large a silhouette.

05-06-09, 12:49 PM	#8
Jimbuna Chief of the Boat Join Date: Feb 2006 Location: 250 metres below the surface Posts: 190,500 Downloads: 63 Uploads: 13	If your harbour raiding, the chances are that you are in very shallow water (10-25 metres on average). How can you expect an ASW not to detect you? Even at silent running it is odds on you will be detected. Try the Scneider cloaking device __________________ Wise men speak because they have something to say; Fools because they have to say something. Oh my God, not again!!

05-08-09, 10:50 AM	#9
Shadowblade Seasoned Skipper Join Date: Jul 2008 Posts: 691 Downloads: 13 Uploads: 0	yes, I was in shallow waters, but I didnt know that I am automatically detected by ASW ships there, because that ASW trawler was far from my sub so I've thought that I was quite safe from the enemy hydrophones... Was it acoustic or visual (automatic) detection ? What about night harbour raiding, are my chances to be stealthy better in night ? How deep sea needs sub to be really stealthy in silent runnning mode ? I understand - no shallow waters , but what about open sea ? __________________ Kapitänleutnant Vlad von Carstein - U-Flotilla Saltzwedel - U-123, Type IXB SH3 GWX 3.0

05-08-09, 11:16 AM	#10
Jaman Gunner Join Date: Apr 2009 Location: Spain Posts: 95 Downloads: 37 Uploads: 0	GWX manual has a secction at the end of it about harbor attacks, but i think this line sums it all pretty well "The GWX Team recommends players stay out of enemy harbors"