I've used them in SH3, but never in SH4 because it feels ahistorical and out of place with the theater. I believe the common procedure in SH3 is to drop a line of them at intervals to make a big sonar target and then depart the line at a right angle, but against multiple escorts I've never seen it work.

Decoys were available very late war and not used much if at all.

yep, most tactics players use in the game are based on real tactics recorded used in the war and since they didnt have decoys untill the war was almost over they never had much time or oportunity to use them enough to develope standard tactics for them.

i cant disable it because the german side actually used decoys but i believe i will remove the decoys icon in GFO because as stated, its not very realistic to have them on fleet boats.

Oh tactics.

Crashdive at flank. when you get to 40 meters and level drop a decoy and go hard to port or starboard 90 degrees(knuckle). When the turn is almost complete drop your speed to 1/3 and rig for silent running. Dive below the thermal layer when the turn is finished. Once below the layer crawl away at 2 knots. Try to keep your stern pointed to the closest escorts sonar contact.

The thermal layer is your best friend,but I try not to be in need of that friend whenever possible.:cool:

Thanks NEON DEON for the info. You describe pretty much my understanding of the technique... dive, 90 degree turn and simultaneous release... maybe a 3 count then reduce speed and run quiet.

I must confess to not being as knowledgeable of the historical details as some of my fellow forum members... and I am likely mixing in tactics from reading about post world war II submarine activity. To be honest I had not noticed any great benefit from using the decoys... but it certainly did not appear to hurt when mixed with other evasion techniques.

One thing is for sure... with a little practice the "stock" escorts are kinda easy to evade (I had read this previously in the forum and now agree)... so I am really practicing for the improved level of prosecution which I expect to find in the RFB mod. Just trying to hone the details so when my new PC arrives on Wednesday I will be ready.

On another note - sometimes it seems the thermal layer is not there... or I am not getting deep enough... or maybe just not announced? Is there typically not a thermal layer above 165 feet when not in open seas? So many questions...

Thanks for the feedback everyone!
Akula4745

Thermal layers or 'thermoclines' are mostly a matter of luck and happenstance. Most US subs by 1944 had a device called a bathythermograph for detecting them, although the game generously gives you this detection ability through the whole war. If you should find a thermal while diving after an attack or even before one one consider yourself blessed.:ping: Although no guarantee of a successful evasion from escorts they are a sub's natural ally.

Because a thermal layer partially deflects or inhibits surface sonar, right?

yes...it bends and refracts it. Here's a pretty good and brief article on the subject from uboat.net

http://www.uboat.net/articles/index.html?article=45

Thanks Torp!!!

Be aware though that in SH4 the thermal layer works "a little different" than it does in the real world. It's really just a percentage reduction to AI sonar and that depends on how it is set in the config files. Because the thermal layer is always there in game (WWII submariners only wished it would always be there) I've set mine to the lowest factor without turning it off completely. Still--that 20% can come in handy :hmmm:. Fire up RFB and make a scenario with just you and 2 Japanese Elite Matsu Escorts in clear weather (0ms winds) and you'll probably see what I mean. Try it using a pre-Gato Class. I dare ya :O:!

Yep. They depend on a variety of environmental conditions that can vary greatly,even within a short distance. But as Torp says,it's really nice to find one,especially when preparing to attack an escorted convoy!:cool:

Hey Montana did you notice that Akula has been promoted to a full Admiral? (going by his shiny new avatar) Not bad for 93 posts. :D

I noticed that. He must have a pipeline to the High Command.:haha:

Now, now gentlemen... yes I am talking to you two, Torp and Montana... since my real life job is closely linked to politics and government I simply had the good sense to make a small contribution to the SUBSIM political action committee. This small contribution along with my relentless badgering of Neal combined (of course) with stories of the Akula orphanage and homeless refuge (I think I also mentioned my painful tennis elbow) lead Neal to promote me recently after reading the letter from my psychiatrist outlining the identity crisis I was experiencing due to my constantly changing forum persona... and it didn't hurt there had been a few too many sake bombs. But do not jump to conclusions - I have not been promoted to Admiral... while my new avatar may appear to be of significant rank, it is actually Vince Osaka, the doorman at the Ichiro strip club and sushi bar (Tuesday is two-for-one tuna rolls and lap dances!).

Say... did I ever tell you guys about my efforts to save the endangered topless beaches in my area? I am always prepared to stand up and fight for a good breast... er, ah... cause. Feel free to contribute as much as you like to my political action group... the Regional Action Committee for Knockers - also known as RACK. If you need more information just let me know....

Be happy... don't worry.
Akula4745