Hedgehogs & Mousetraps & Bears, Oh My - Not RHS

[JWE]

ORIGINAL: AlaskanWarrior
Okay, please define shallow and deep in numbers and not some ephemeral term. I calculated that the hits on the third sub England sank were roughly 140 feet deep (18.5 sec from launch, ~12 sec flight time so 6.5 seconds of sink at 22 fps = ~140 feet).

In game terms, shallow water is evaluated in a couple contexts. If the sub is in a "coastal shallow" hex, then the max bottom is 150'. If the sub is in an offshore 'shallow' hex, then the bottom (CombatDepth) variable ranges from between 100' to 150'. All evaluated against whether combat is in the context of an ASW TF, or the escort of some other TF.

[Andrew Brown]

ORIGINAL: JWE
In game terms, shallow water is evaluated in a couple contexts. If the sub is in a "coastal shallow" hex, then the max bottom is 150'. If the sub is in an offshore 'shallow' hex, then the bottom (CombatDepth) variable ranges from between 100' to 150'. All evaluated against whether combat is in the context of an ASW TF, or the escort of some other TF.

Interesting. Haven't heard this before.

FWIW for the AE map I used the figure of 100m (about 330') as the cutoff point between deep and shallow ocean. Assuming an even slope angle for the continental shelves (I have no idea whether it really is always even) this equates to an average depth of a shallow ocean hex of 50m (about 165'). As far as I can tell the stock map uses a shallow/deep cutoff of 200m.

Andrew

[JWE]

ORIGINAL: Andrew Brown

ORIGINAL: JWE
In game terms, shallow water is evaluated in a couple contexts. If the sub is in a "coastal shallow" hex, then the max bottom is 150'. If the sub is in an offshore 'shallow' hex, then the bottom (CombatDepth) variable ranges from between 100' to 150'. All evaluated against whether combat is in the context of an ASW TF, or the escort of some other TF.

Interesting. Haven't heard this before.

FWIW for the AE map I used the figure of 100m (about 330') as the cutoff point between deep and shallow ocean. Assuming an even slope angle for the continental shelves (I have no idea whether it really is always even) this equates to an average depth of a shallow ocean hex of 50m (about 165'). As far as I can tell the stock map uses a shallow/deep cutoff of 200m.

Andrew

It's just a 'depth' parameter used to compare the "range" of a DC with the "depth" of a sub for combat purposes. It's a way to get better odds in Witp stock.

Pretty sure algorithm hasn't changed a lot for AE. Might be a nice thing to look at, now you brought it up. Ciao, Andrew.

John

[herwin]

ORIGINAL: JWE

ORIGINAL: Andrew Brown

ORIGINAL: JWE
In game terms, shallow water is evaluated in a couple contexts. If the sub is in a "coastal shallow" hex, then the max bottom is 150'. If the sub is in an offshore 'shallow' hex, then the bottom (CombatDepth) variable ranges from between 100' to 150'. All evaluated against whether combat is in the context of an ASW TF, or the escort of some other TF.

Interesting. Haven't heard this before.

FWIW for the AE map I used the figure of 100m (about 330') as the cutoff point between deep and shallow ocean. Assuming an even slope angle for the continental shelves (I have no idea whether it really is always even) this equates to an average depth of a shallow ocean hex of 50m (about 165'). As far as I can tell the stock map uses a shallow/deep cutoff of 200m.

Andrew

It's just a 'depth' parameter used to compare the "range" of a DC with the "depth" of a sub for combat purposes. It's a way to get better odds in Witp stock.

Pretty sure algorithm hasn't changed a lot for AE. Might be a nice thing to look at, now you brought it up. Ciao, Andrew.

John

So the shallow/deep line is at the continental shelf. That does correspond fairly well to the shallow/deep distinction in the sonar literature. In shallow waters, the sonar can 'see' to the bottom. You have larger reverberation levels and propagation loss levels, much greater and more confusing acoustic clutter, and submarines can hide better. Then you also have littoral or coastal waters, and those magnify the difficulties of ASW in shallow waters. So, in shallow or littoral waters, the sub can't evade attack quite as well, but its detect-ability is way down, so it's more, not less, effective. The game has it backwards. That explains why my doctrinal use of subs in the current game has been running into problems.

[el cid again]

ORIGINAL: Andrew Brown

ORIGINAL: JWE
In game terms, shallow water is evaluated in a couple contexts. If the sub is in a "coastal shallow" hex, then the max bottom is 150'. If the sub is in an offshore 'shallow' hex, then the bottom (CombatDepth) variable ranges from between 100' to 150'. All evaluated against whether combat is in the context of an ASW TF, or the escort of some other TF.

Interesting. Haven't heard this before.

FWIW for the AE map I used the figure of 100m (about 330') as the cutoff point between deep and shallow ocean. Assuming an even slope angle for the continental shelves (I have no idea whether it really is always even) this equates to an average depth of a shallow ocean hex of 50m (about 165'). As far as I can tell the stock map uses a shallow/deep cutoff of 200m.

Andrew

Most mapmakers use the 100 fathom curve - more or less 200 meters.

[JWE]

ORIGINAL: Andrew Brown

ORIGINAL: JWE
In game terms, shallow water is evaluated in a couple contexts. If the sub is in a "coastal shallow" hex, then the max bottom is 150'. If the sub is in an offshore 'shallow' hex, then the bottom (CombatDepth) variable ranges from between 100' to 150'. All evaluated against whether combat is in the context of an ASW TF, or the escort of some other TF.

Interesting. Haven't heard this before.

FWIW for the AE map I used the figure of 100m (about 330') as the cutoff point between deep and shallow ocean. Assuming an even slope angle for the continental shelves (I have no idea whether it really is always even) this equates to an average depth of a shallow ocean hex of 50m (about 165'). As far as I can tell the stock map uses a shallow/deep cutoff of 200m.

Andrew

Hi Andrew. BTW, I’ll make you a pdf of the Bowditch section on bottom, along with contour, and pm it to you. Where you pick the shallow/deep contour is your choice. Even today, the only hydrographic definition of shallow is low mean tide water, but the Bowditch I’ll send you will make that clear. So pick your contour & go with it. Glad to talk to you about it if you have questions. Basically, use any of the nominal contours, so long as it’s consistent. Ciao.

John

[witpqs]

ORIGINAL: herwin

So the shallow/deep line is at the continental shelf. That does correspond fairly well to the shallow/deep distinction in the sonar literature. In shallow waters, the sonar can 'see' to the bottom. You have larger reverberation levels and propagation loss levels, much greater and more confusing acoustic clutter, and submarines can hide better. Then you also have littoral or coastal waters, and those magnify the difficulties of ASW in shallow waters. So, in shallow or littoral waters, the sub can't evade attack quite as well, but its detect-ability is way down, so it's more, not less, effective. The game has it backwards. That explains why my doctrinal use of subs in the current game has been running into problems.

Maybe - JWE can you look into this with the team? Certainly subs are more easily attacked in shallow water in WITP, but what about detectability? So subs in shallow water should be:

A) Less detectable

AND

B) Easier to attack

[JWE]

ORIGINAL: witpqs
Maybe - JWE can you look into this with the team? Certainly subs are more easily attacked in shallow water in WITP, but what about detectability? So subs in shallow water should be:

A) Less detectable

AND

B) Easier to attack

I can do this, but you have to understand that Harry is describing what he thinks is IRL. It’s way OT for the thread, which is ‘how does the code work so a modder can understand what to do and why’. The code is. Real life is irrelevant. You have to think relationally. Resistance is futile.

But .. A) subs in shallow water less detectable ??? Sorry Harry, no. The game is good here; and B) easier to attack .. yes, game is good here too.

Game algorithms seem to be reasonable. IRL people can always come up with something, but we live with what we got, and what we got isn’t that bad.

Just what exactly, do you need to know ?? Ciao.

John

[herwin]

ORIGINAL: JWE

ORIGINAL: witpqs
Maybe - JWE can you look into this with the team? Certainly subs are more easily attacked in shallow water in WITP, but what about detectability? So subs in shallow water should be:

A) Less detectable

AND

B) Easier to attack

I can do this, but you have to understand that Harry is describing what he thinks is IRL. It’s way OT for the thread, which is ‘how does the code work so a modder can understand what to do and why’. The code is. Real life is irrelevant. You have to think relationally. Resistance is futile.

But .. A) subs in shallow water less detectable ??? Sorry Harry, no. The game is good here; and B) easier to attack .. yes, game is good here too.

Game algorithms seem to be reasonable. IRL people can always come up with something, but we live with what we got, and what we got isn’t that bad.

Just what exactly, do you need to know ?? Ciao.

John

I'll just point you at a few open-source links:

Sea Technology
Warfare summaries
Commander's academy and dive center
Littoral ASW
French perspective
US Navy budget item

I worked on BSY-2 and NSSN, my PhD is in high frequency airborne biosonar, my lab is working on sonar systems for use in cluttered environments, and I also have a background in underwater biosonar. I'm telling you the detection problem is (much) harder in shallow and littoral water environments.

[JWE]

I'm sure you are very smart. But .. it’s way OT for the thread, which is ‘how does the code work so a modder can understand what to do and why’. The code is. Real life is irrelevant wrt the topic of this thread.

Maybe you could put your thoughts somewhere else. maybe someone would be interested. Otherwise, you are just hijacking. Please go elsewhere. Thank you.

[herwin]

ORIGINAL: JWE

I'm sure you are very smart. But .. it’s way OT for the thread, which is ‘how does the code work so a modder can understand what to do and why’. The code is. Real life is irrelevant wrt the topic of this thread.

Maybe you could put your thoughts somewhere else. maybe someone would be interested. Otherwise, you are just hijacking. Please go elsewhere. Thank you.

You miss my point. You wrote "subs in shallow water less detectable ??? Sorry Harry, no. The game is good here". I was just trying to point out that the game is not good here, and it affects gameplay--people coming in from the real world with a background in ASW get blind-sided, and it makes the game company look like a bunch of fools--sorry about the French--to defend it. I'm not trying to sound smart--I'm trying to give you some advice while staying in the open literature. I know it won't be fixed, but you need to file a problem report.

[el cid again]

ORIGINAL: JWE

I'm sure you are very smart. But .. it’s way OT for the thread, which is ‘how does the code work so a modder can understand what to do and why’. The code is. Real life is irrelevant wrt the topic of this thread.

Maybe you could put your thoughts somewhere else. maybe someone would be interested. Otherwise, you are just hijacking. Please go elsewhere. Thank you.

It is curious that JWE started these useful threads and does not understand why and how they are useful? Herwin is correct - we need to know what the target is AS WELL as how code works IF we are to end up with the most realistic possible mods. Can't get there without both - so Herwin is not off topic. It is not the first time JWE said this - nor that somehow comments from all are not welcome - but that is not how a Forum works - either in theory or in practice. JWEs threads are going to have a significant impact - among other things speeding up the game turn processing (indirect effect and unintended) as well as contributing to more survivable submarines - and better relative ratings for AS units - and possibly adding whole new kinds of AS weapons. So we are in his debt - in spite of his confusion and even hostility toward some comments on "his" threads.

[Sardaukar]

Didn't Hedgehog have some problems with reliability, in sense that many bombs failed to detonate, at least earlier ?

[JWE]

ORIGINAL: Sardaukar

Didn't Hedgehog have some problems with reliability, in sense that many bombs failed to detonate, at least earlier ?

That may well be true. Don’t know.

But the code only consults specific ‘device’ variables for each combat routine. It doesn’t consult the ‘dud rate’ variable for ASW combat, so even if you put something into that field, it wouldn’t have any effect.

If this is important to you, what you could do is add additional Hedgehog “devices” to the Device database, with defined upgrade paths, and adjust the “accuracy” parameter, to account for your reliability issues.

Since the code only recognizes ‘hits’ vs ‘not hits’, the reason ‘why’ any particular drop doesn’t do the deed, is irrelevant. You can skew the results by adjusting the accuracy variable.

Ciao. John

[el cid again]

ORIGINAL: Sardaukar

Didn't Hedgehog have some problems with reliability, in sense that many bombs failed to detonate, at least earlier ?

It probably had a problem with blowing up the ship. A DE was lost credited to Mousetrap contact fused projectiles. That means Hedgehog equipped ships were at risk - they used the same projectile.

HH was not effective at first - and it eventually became even more effective than when it did finally start to score. They had to learn how to use it tactically. It normally does not detonate - if it does not hit. It was a British invention - and it is well covered in Secret Weapons of World War Two (one of several books by that title, this one is on Allied weapons - others of the same title are on German weapons. There is good information in Naval Weapons of World War Two in British and American sections.

[Dili]

But the code only consults specific ‘device’ variables for each combat routine. It doesn’t consult the ‘dud rate’ variable for ASW combat, so even if you put something into that field, it wouldn’t have any effect.

 
What are the devices where dud rate works?

[JWE]

ORIGINAL: Dili

But the code only consults specific ‘device’ variables for each combat routine. It doesn’t consult the ‘dud rate’ variable for ASW combat, so even if you put something into that field, it wouldn’t have any effect.

What are the devices where dud rate works?

Well, there's torpedoes,

Maybe couple others, have to look, take a while, there's a lotta lines.

Ciao. John

[JWE]

Yep, just torpedoes. Reason seems to be that the designers established a date dependent set of routines that reduces dud rate in accord with game month/year. It could be they did this to obviate the multiplication of devices, with serial introduction dates and decreasing dud rates, for US torps.

The point for fantasy modders to consider is the “dud rate” is hard coded. If DudRate is > A, and Date > B, then DudRate = C; don’t matter where you put it, if it’s >A, and Date > B, then it is C. You can make them better than they were, but you can’t make them worse, beyond periodicity.

Ciao. John

[chuckwalla]

I'm not sure I completely follow so let's take a concrete example from a widely played mod. The Big-B Mod v1.4 increases the dud rate on the Type 91 18" aerial torpedo from the stock value of 10% to 25%. Does it start out at 25% and decline over time according to hard code or does it simply revert to a hard coded value and the 25% changes nothing.

[JWE]

ORIGINAL: chuckwalla

I'm not sure I completely follow so let's take a concrete example from a widely played mod. The Big-B Mod v1.4 increases the dud rate on the Type 91 18" aerial torpedo from the stock value of 10% to 25%. Does it start out at 25% and decline over time according to hard code or does it simply revert to a hard coded value and the 25% changes nothing.

M’kay. Let’s have device type = 16 (torpedo). Delivery system doesn’t matter, ship or plane (subs treated slightly different).

The game looks at the “game month” and if it is > than month=A (for example) AND dud rate is > 20, then dud rate = 10. If your weapon is < 20, you keep it. If it is > 20, it reduces.

Thing is you can have BIG dud rates, early war, but they will collapse into reasonable limits as time goes on. If you have small dud rates, early war, they will hold up until they collapse into the code values. Everything, over time, collapses into about dud rate = 10.