Depth charts??

[BitznBites]

Howdy....
Is there a mod that would show the sea depth, especially the shallow depth around the coasts of England, the Channel, and Spain? People have been sailing there for centuries and I know they had accurate data during WW 2 and surely the sub drivers would have had this info. It would be nice to be able to know where deeper water is so if I need to dive deeper I can turn in that direction or set up my patrol so I am near deeper water.
Thanks.....

[Johnfb]

Originally Posted by BitznBites

Howdy....
Is there a mod that would show the sea depth, especially the shallow depth around the coasts of England, the Channel, and Spain? People have been sailing there for centuries and I know they had accurate data during WW 2 and surely the sub drivers would have had this info. It would be nice to be able to know where deeper water is so if I need to dive deeper I can turn in that direction or set up my patrol so I am near deeper water.
Thanks.....

Your officer can give you depth readings as you sail in real time.
The MaGiu has a depth "ruler" in it with different colours showing different depths

[BigWalleye]

When operating in open sea areas, it was not practical to use small-scale hydrographic features tactically. Only harbors, bays, and shorelines were charted with sufficient accuracy to show features smaller than a km or so. Even inshore, the problem was knowing your own position precisely enough, especially when submerged. You could, and can, distinguish trends - head toward the river mouth, then turn seaward. And you could distinguish the 10- and 30-fathom curves and use them constructively. But you couldn't drop the sub into a "deep hole" to hide. Not only were you unlikely to know the existence of the hole (except in shallow water) but you were even less likely to know where your boat was in relation to the hole.

One difficulty was that a submerged sub moves so slowly. At 5 kt, pretty good submerged speed, the sub will cover 1 km in about 11 minutes. That's time for two depth change runs by a DD that has you located, more if there are more DDs. That doesn't give you a lot of opportunity to use hydrographic features for evasion. All you can do is use the bottom contours as shown on the nav chart, and try to make use of the trends. From what I have read, that was pretty much all they actually did, and you can do the same thing in the game.

[Kielhauler1961]

Funny this topic should come up. I stumbled across this website the other day while looking for something else:

http://www.kartengruppe.it/

Probably too detailed for tactical use as BigWalleye mentions, but interesting to look at nevertheless.

KH

[Aras]

Another thing about realism :

If you use active sonar (depth under keel) while a DD is using passive sonar, they couldn’t pin point your location however there will be aware of your existence. This is not simulated in the game.

[BigWalleye]

Neat maps, Kielhauler. I am not able to read the soundings on the copy I downloaded. Is it possible to downlaod a higher-res version?

The soundings appear to be about a couple of km apart even in the shallowest areas. Harbor charts would have even denser depth information, but it is difficult to use effectively. And it is not clear how fine the mesh is that is used to represent the bottom in the game. A cool-looking chart like these wouldn't be much use oif the game doesn't model any of the detail.

Aras, you bring up another good point. As Rockin' Robbins said: "Realism isn't about game settings. It's about how you play." Depth sounding is one of those areas where you have to decide on your own level of realism.

[Paulebaer1979]

Originally Posted by Aras

Another thing about realism :

If you use active sonar (depth under keel) while a DD is using passive sonar, they couldn’t pin point your location however there will be aware of your existence. This is not simulated in the game.

A ship near your sub is only able to hear your active-sonar (depth under keel) if it has a passive sonar for the frequence of your active sonar. If not, it can´t find you, because the frequence of the echolot is in frequence which humans can´t hear - dogs perhaps, but they do not sit at an sonar operator desk.

[GJO]

When I started playing SH3 - I often lost my career early on because I had tried to dive too deep in shallow water. These days I tend to plan attacks on escorted convoys where I know I have at least 200 Metres under the keel and always ping the depth before diving. If I have a criticism of the game it is that it doesnt allow a submarine to settle onto the bottom or dock against land without incurring serious damage. In real life there must be many locations where it is possible to do this provided the approach is gently and slow.

[BitznBites]

I guess what I was hoping for would be a more detailed in game map that had the depth gradients more plainly marked. Perhaps actual depth numbers or clear topographic lines. I know they could not be real accurate but a general indication that it is deeper over there and about this deep, and shallower over there about that deep. I know that if there is some hump or hole there you would not know and might run into it and damage the sub, but if you knew that a river channel ran from about here to about there, you could get into it and get deeper. The in game map is a little too vague for my liking, I think the sub navigators would have a little better info....Maybe not.
Thanks...

[BigWalleye]

Originally Posted by Paulebaer1979

A ship near your sub is only able to hear your active-sonar (depth under keel) if it has a passive sonar for the frequence of your active sonar. If not, it can´t find you, because the frequence of the echolot is in frequence which humans can´t hear - dogs perhaps, but they do not sit at an sonar operator desk.

The ASDIC search beam frequency was well above human heaing range. The ping-ping-ping is a Hollywood thing, just as (apparently) is the single ping from the Echolot. So it's hardly a safe bet that the British DDs wouldn't be able to catch the Echolot xmission.

[Paulebaer1979]

Originally Posted by BigWalleye

The ASDIC search beam frequency was well above human heaing range. The ping-ping-ping is a Hollywood thing, just as (apparently) is the single ping from the Echolot. So it's hardly a safe bet that the British DDs wouldn't be able to catch the Echolot xmission.

It´s easy physic: the echolot pings only directly down to the bottom and the beam is very small. So if a DD wishes to be able to listen to the echolot, his sonar receiver has to be under the submarine - the best position for every DD

I learned that facts during my time in the german navy 2001 - 2009. We often used the echolot during exercises with anti-sub-fregattes near us - they didn´t find us.

[Tycho]

Originally Posted by BitznBites

I guess what I was hoping for would be a more detailed in game map that had the depth gradients more plainly marked. Perhaps actual depth numbers or clear topographic lines. I know they could not be real accurate but a general indication that it is deeper over there and about this deep, and shallower over there about that deep.

Try this mod from "verte": http://www.subsim.com/radioroom/showthread.php?t=164173
With only 4 gradient levels:
~0-50m
~50-100m
~100-150m
~>150m
My map look like this:




Gradients are clearly visible and I see where is deeper in shallower water and opposite.


~0-50m



~50-100m

[Kielhauler1961]

Originally Posted by BigWalleye

Neat maps, Kielhauler. I am not able to read the soundings on the copy I downloaded. Is it possible to downlaod a higher-res version?

I downloaded the Kiel Bight map (felt homesick...) and achieved a good resolution when I zoomed in. I have a high definition monitor though. Maybe higher res ones are available for purchase? Contact the website and ask.

On another matter, I have noticed that many kameraden here think that putting their boat on the seabed somehow makes it invisible? My reading of WW2 anti-submarine operations has revealed a number of occasions when surface ships attacked non-sub targets and wasted countless wasserbomben on sunken wrecks.

I was reading only the other day about one RN destroyer that spent most of one day pounding the wreck of a U-Boat sunk in that area the year before and then had the cheek to put in a claim for a fresh one. The Admiralty said no.

Imagine that. Even after the swine have sunk you they won't leave you to rust in peace. Being sunk once is unfortunate. Being sunk twice is just bad manners...

If a poor, innocent non-metallic whale or skeletal hulk from WW1 can attract attention then what makes a U-Boat so special? 750 tons of Krupp steel is going look odd against a background of mud and silt.

I think the only seafloor safe enough to avoid detection is the one over 1000m deep, but that brings it's own problems.

KH

[BigWalleye]

Originally Posted by Kielhauler1961

I downloaded the Kiel Bight map (felt homesick...) and achieved a good resolution when I zoomed in. I have a high definition monitor though.

Oh. snap! 1920 by 1280 not good enough?

But, the map image is only 1200x984.

On another matter, I have noticed that many kameraden here think that putting their boat on the seabed somehow makes it invisible? My reading of WW2 anti-submarine operations has revealed a number of occasions when surface ships attacked non-sub targets and wasted countless wasserbomben on sunken wrecks.

I was reading only the other day about one RN destroyer that spent most of one day pounding the wreck of a U-Boat sunk in that area the year before and then had the cheek to put in a claim for a fresh one. The Admiralty said no.

Imagine that. Even after the swine have sunk you they won't leave you to rust in peace. Being sunk once is unfortunate. Being sunk twice is just bad manners...

If a poor, innocent non-metallic whale or skeletal hulk from WW1 can attract attention then what makes a U-Boat so special? 750 tons of Krupp steel is going look odd against a background of mud and silt.

I think the only seafloor safe enough to avoid detection is the one over 1000m deep, but that brings it's own problems.

KH

Hey, it always seems to work in the movies! (Wish I had a dollar for even post on this forum that cites some movie as a historical reference.)

[maillemaker]

It would have been interesting to see a before/after of that wreck!

Steve