[REL] Depth charge water disturbances

CCIP · 03-19-11, 12:25 PM

This is gonna make IRAI very, very interesting indeed. Great work, looking forward to having a go at this soon!

TheDarkWraith · 03-19-11, 12:34 PM

Quote:

Originally Posted by CCIP

This is gonna make IRAI very, very interesting indeed. Great work, looking forward to having a go at this soon!

I figure that once we get it 'tweaked' to where it needs to be this can be added into IRAI

. Currently there are some values in it that I'm not very sure what they do or how they impact the game.

The mod works like this:
I hook the events for the depth charge explosions and create a virtual bold decoy for each explosion event. Simple and elegant

Bilge_Rat · 03-19-11, 02:12 PM

very nice. Tested it in the PQ-17 mission, still got killed, but I could tell the escorts lost me a few time and had trouble regaining contact.

As to how long the disturbance should last. I never found any solid info on that, but in the sonalyst sims (688i/SC/DW) where that effect is modeled, the effect of an underwater explosion can last from 30-60 seconds which seems about right to me. It's not just the initial explosion that masks the noise, but also the fact that the water molecules are all scrambled and mask the noise, much like a dust cloud that remains after an explosion.

Anyhow, I want to congratulate TDW on solving a major problem in the SH series.

btw, how do I edit the file if I want to try out some personal changes?

stoianm · 03-19-11, 02:16 PM

Quote:

Originally Posted by Bilge_Rat

very nice. Tested it in the PQ-17 mission, still got killed, but I could tell the escorts lost me a few time and had trouble regaining contact.

As to how long the disturbance should last. I never found any solid info on that, but in the sonalyst sims (688i/SC/DW) where that effect is modeled, the effect of an underwater explosion can last from 30-60 seconds which seems about right to me. It's not just the initial explosion that masks the noise, but also the fact that the water molecules are all scrambled and mask the noise, much like a dust cloud that remains after an explosion.

Anyhow, I want to congratulate TDW on solving a major problem in the SH series.

btw, how do I edit the file if I want to try out some personal changes?

With S3D... se here:

regards

TheDarkWraith · 03-19-11, 05:19 PM

Quote:

Originally Posted by Bilge_Rat

As to how long the disturbance should last. I never found any solid info on that, but in the sonalyst sims (688i/SC/DW) where that effect is modeled, the effect of an underwater explosion can last from 30-60 seconds which seems about right to me. It's not just the initial explosion that masks the noise, but also the fact that the water molecules are all scrambled and mask the noise, much like a dust cloud that remains after an explosion.

that's more solid concrete info than me pulling numbers out of the air

Should I update the mod to use a lifetime of 30 seconds then for each DC explosion

Feedback please. As much as I love to add randomness to things like this I cannot on this one. I have to set an exact time.

charognard · 03-20-11, 01:44 AM

http://en.wikipedia.org/wiki/Hedgehog_(weapon)

An unsuccessful attack does not hide the submarine from sonar.
When a depth charge explodes it can take 15 minutes before the disturbance can settle down enough that sonar becomes effective. Many submarines escaped during the time after an unsuccessful depth charge attack. Since Hedgehog charges only explode on contact, if they miss, the submarine can still be tracked by sonar.

Well a DC make 15min maximum disturbance time.

Didd · 03-20-11, 04:02 AM

I don't know if it's relevant, but in my fishing boat, if I pass astern of something like a ferry, then the depth sounder goes all screwy for a good distance behind the ferry, presumably due to aeration and/or turbulance. I would hazard a guess that this would persist for at least a good 60s after the ferry passes.

Bilge_Rat · 03-20-11, 08:54 AM

Surprisingly there seems to be little written on this. I checked my copy of S.E. Morison's "history of U.S. naval operations in WW2" which has 2 volumes on the battle of the atlantic. He has a whole chapter on ASW doctrines and problems, but never discusses this issue.

However, based on the various comments. I changed my copy to a 5 minute delay and tested it on the PQ-17 mission again.

Unfortunately, I wound up sneaking through the escort screen undetected:

...then torpedoed 2 freighters...

...then snuck away without getting detected...which I guess was not the point..

I will retest..

03-19-11, 12:25 PM	#1
CCIP Navy Seal Join Date: Apr 2005 Location: Waterloo, Canada Posts: 8,700 Downloads: 29 Uploads: 2	This is gonna make IRAI very, very interesting indeed. Great work, looking forward to having a go at this soon! __________________ There are only forty people in the world and five of them are hamburgers. -Don Van Vliet (aka Captain Beefheart)

03-19-11, 02:12 PM	#3
Bilge_Rat Silent Hunter Join Date: Apr 2002 Location: standing watch... Posts: 3,855 Downloads: 344 Uploads: 0	very nice. Tested it in the PQ-17 mission, still got killed, but I could tell the escorts lost me a few time and had trouble regaining contact. As to how long the disturbance should last. I never found any solid info on that, but in the sonalyst sims (688i/SC/DW) where that effect is modeled, the effect of an underwater explosion can last from 30-60 seconds which seems about right to me. It's not just the initial explosion that masks the noise, but also the fact that the water molecules are all scrambled and mask the noise, much like a dust cloud that remains after an explosion. Anyhow, I want to congratulate TDW on solving a major problem in the SH series. btw, how do I edit the file if I want to try out some personal changes? __________________

03-20-11, 01:44 AM	#6
charognard Navy Dude Join Date: Feb 2009 Posts: 171 Downloads: 201 Uploads: 0	http://en.wikipedia.org/wiki/Hedgehog_(weapon) An unsuccessful attack does not hide the submarine from sonar. When a depth charge explodes it can take 15 minutes before the disturbance can settle down enough that sonar becomes effective. Many submarines escaped during the time after an unsuccessful depth charge attack. Since Hedgehog charges only explode on contact, if they miss, the submarine can still be tracked by sonar. Well a DC make 15min maximum disturbance time. __________________ Gwx 3.0 / Rbs1_SH4_Effects_GWX_30_71 / Water Stream for Uboats / REAL U-505 item graphics for slide-out compass / SH3 Commander 3.2 /SH3 Commander Config files for GWX 3.0

03-20-11, 08:54 AM	#8
Bilge_Rat Silent Hunter Join Date: Apr 2002 Location: standing watch... Posts: 3,855 Downloads: 344 Uploads: 0	Surprisingly there seems to be little written on this. I checked my copy of S.E. Morison's "history of U.S. naval operations in WW2" which has 2 volumes on the battle of the atlantic. He has a whole chapter on ASW doctrines and problems, but never discusses this issue. However, based on the various comments. I changed my copy to a 5 minute delay and tested it on the PQ-17 mission again. Unfortunately, I wound up sneaking through the escort screen undetected: ...then torpedoed 2 freighters... ...then snuck away without getting detected...which I guess was not the point.. I will retest.. __________________

03-20-11, 04:02 AM	#7
Didd Seaman Join Date: Dec 2009 Location: Orkney Posts: 33 Downloads: 90 Uploads: 0	I don't know if it's relevant, but in my fishing boat, if I pass astern of something like a ferry, then the depth sounder goes all screwy for a good distance behind the ferry, presumably due to aeration and/or turbulance. I would hazard a guess that this would persist for at least a good 60s after the ferry passes.