Depth-charge turbulence

[Floater]

Originally Posted by urseus

Im very suprised that the depth charge blindness isnt modeled. Ive been doing that alot recently, speeding up during a depth charge run.

Do you have any proof that its not in the game?

Not proof as such, just enough evidence for me to be convinced that it's not modelled. I described that evidence up-thread - I've seen this before, but this is the first time I've deliberately tried to test it, and the approaching DD matched my every move almost instantly despite the DCs exploding close by less than a minute previously.

Let's not mix up the turbulence created with depth charges (which isn't working) with the sonar cone and speed blindness of a nearby attacking DD (which is, AFAICT).

[urseus]

Hang on isnt it the same thing?

They drop their charges over you...meaning you can speed up alot for about 30 seconds maybe while the expolsions are going on.

[Kpt. Lehmann]

Would that be the "Speedy Jameson" Irish whiskey maneuver?

[yankee-V]

Jameson?! No, that's the "John Full Power" maneuver.

[FAdmiral]

Floater, I'm not sure that being submerged in the middle of a
convoy will mask your sounds either. I got into one on my last
patrol and the 2 escorts seemed to have me detected almost
immediately as they approached. The only thing that saved me was they had to stop & reverse to keep away from the merchants.


JIM

[big_feef]

I've noticed this too, the 'sonic freedom' window after a dc attack to hit flank speed seems to be more than 30 seconds, but less than a minute. Pushing it past 30 seconds tends to get you re-acquired by the enemy sonar 100% of the time.

I usually play at high realism and without the external camera; but when checking this aspect of the game out, I noticed the enemy destroyers following my course turn for turn right after close proximity dc attacks. That should not be possible.

To counter this, I usually do stern shot on my first few targets when attacking a convoy. That way, I should have one or two stationary ships to hide under when the escorts come calling. They'd run around trying to get at me while I slowly go deep until they eventually lose me on their sonar. Unfortunately, this doesn't work that well in stormy weather for obvious reasons.

This short window of 'sonic freedom' after a dc attack isn't that bad early in the war; but as the ASW technology improves around '42-'43 (hedgehogs especially), you have to be very lucky to escape unscathe from a single destroyer dc run... If you're being attacked by more than three, you can just forget it usually.

[Col7777]

While we are on the subject of DC's and being detected etc, how good are the decoys when activated, as yet I haven't tried that?

[CB..]

Originally Posted by Col7777

While we are on the subject of DC's and being detected etc, how good are the decoys when activated, as yet I haven't tried that?

the decoys seem pretty good to me Col!
(i usually place one in an emergency at around 50 metres depth in a crash dive then immediately go to ahead slow and silent running and head deeper after making a slight turn)

BUT here's the problem...

one decoy is a decoy...two is a trail of bread crumbs!!!

[Floater]

I agree with CB - deploying BOLD decoys has saved my boat on several occasions. When you're detected, sling out a single canister, go silent and deep and turn your rear towards the DD. It works quite impressively, as it did in real life.

I'm not sure about the later years, though - I've never played past mid-'44. Experienced ASDIC operators could tell the difference between bubbles and subs, mainly because the bubbles don't move in the same way and the sound of the returns was slightly different.

Frankly, I've always found it amazing that a cloud of bubbles could give anything like the sonic return of a tube of steel, but apparently they did.

[Floater]

Originally Posted by U-104

I think it is in SH3. Once on a patrol I was under depth charge attack by a DD. As it entered its charge, I hit flank. It came over head and dropped its depth charges. They exploded behind my sub. I went at flank speed for 5 minutes then went ahead slow and it never found me again.

With a lone DD, or with a group of DDs that are not communicating your position, that's understandable. An attacking DD is blind from the moment he speeds up for the depth-charge run - anything over about eight knots and his sonar gear is useless. Then, after he's passed over you, it takes time to (a) slow down again and (b) turn around to get you out of his baffles. A good DD captain could reacquire a target about two minutes after dropping the DCs, but it often took much longer, particularly with the larger DDs.

It's in areas like that that the corvette really came into its own. Being small, they had a tight turn radius, and were also able to accelerate and decelerate much more quickly than a destroyer.

[Shadow9216]

I recently had an encounter that caused me to rethink the whole AI issue...an armed trawler circled my position for several hours of game time despite me doing 1 knot (!), then going all stop and silent running. I was at PD, then 20m, 30m, 50m...finally at 100m he circled for about an hour, then left.

From this same convoy I had deleted :P two T-2s, a C-3, crippled a C-2, and bagged an aux cruiser. I had been aggressively pinged by the Black Swan and Flower that were guarding it, but managed to slip them by using the tactics above.

So how was the trawler able to keep contact? Maybe he was actually trawling, and I was hooked in a net? Otherwise, how was he able to literally circle me- I used the external cam to confirm this, plus my hydrophones- for hours?

[Col7777]

It MAY have been because you stopped and restarted your engines, I believe the sudden noise from this could give you away again, I'm not sure if it is modelled in the sim though.

[U-104]

Originally Posted by Shadow9216

Maybe he was actually trawling, and I was hooked in a net?

a uboat did do that once.

[Shadow9216]

It MAY have been because you stopped and restarted your engines, I believe the sudden noise from this could give you away again, I'm not sure if it is modelled in the sim though

No, he lost me after I stopped the engines- but not until I had been completely dead in the water for about an hour.

So how was he able to perform complete circles around my boat, despite my slow speed, course changes, etc? If I turned to 090, he followed, turning in a perfect circle with me in the center. Turn to 345, same thing, 209, 014, didn't matter. Finally I figured that, even at 1 knot (I manually set the speed), I must be making enough noise to hear- so I went all quiet. He circled, then went away...

[oRGy]

If the sonar blindness from depth charging *is* modelled *but* set to a too low time, then its value is going to be somewhere. Probably in data/Library. I might have a look for it later - starting to almost enjoy hex editing. However I haven't suffered any dd attacks yet (1940)