Ship Class Design

[Erik2]

ORIGINAL: sapper32

Hi was just reading through this and noticed under battlecruisers you have UK Roberts is there a reason for this as if im correct ?? Roberts is a monitor regards Ian

'Roberts' is from Robert's (Bob's) AKA Curtis' original Excel sheet.
Hope that was clear [:)]

[rhinobones]

If you haven’t seen it already, there is a ship modeling site named Steelnavy.com

http://steelnavy.com/

The site is loaded with a lot of very good and knowledgeable people who eat and breathe everything to do with ships . . . especially warships. I’m sure there are people there who would gladly review your spreadsheet and offer suggestions for adjusting the relative strengths and weakness of the various ships and ship classes. Sure that they would also offer suggestions for ships you do not have on the spreadsheet.

One thing I have noticed is the lack of upgrading of AA defense for the WWII ships. There is a big difference in the capabilities of 1940 AA defense as compared to 1943 and 1945. The people at Steelnavy can help you with that.

Regards RhinoBones

[larryfulkerson]

ORIGINAL: rhinobones

If you haven’t seen it already, there is a ship modeling site named Steelnavy.com

http://steelnavy.com/

The site is loaded with a lot of very good and knowledgeable people who eat and breathe everything to do with ships . . . especially warships. I’m sure there are people there who would gladly review your spreadsheet and offer suggestions for adjusting the relative strengths and weakness of the various ships and ship classes. Sure that they would also offer suggestions for ships you do not have on the spreadsheet.

One thing I have noticed is the lack of upgrading of AA defense for the WWII ships. There is a big difference in the capabilities of 1940 AA defense as compared to 1943 and 1945. The people at Steelnavy can help you with that.

Regards RhinoBones

Here's what Rhino said: (I think....)

Si no lo has visto ya, hay una nave que modela Steelnavy.com nombrado sitio
http://steelnavy.com/
El sitio se carga con muchos de la gente muy buena y bien informada que come y respira todo para hacer con las naves. especialmente buques de guerra. Soy seguro que hay gente allí quién repasaría alegre tu hoja de balance y ofrecería las sugerencias para ajustar las fuerzas y la debilidad relativas de las varias naves y clases de la nave. Seguro que también ofrecerían las sugerencias para las naves no tienes en la hoja de balance. Una cosa que he notado es la carencia del aumento de la defensa del AA para las naves de WWII. Hay una diferencia grande en las capacidades de la defensa 1940 del AA con respecto a 1943 y a 1945. La gente en Steelnavy puede ayudarte con eso.

but here's what Google says that translates into English:

If you have not seen it already, is a ship that Steelnavy.com models named http://steelnavy.com/ site the site load with many of well informed very good people and that it eats and it breathes everything to do with the ships. specially ships military. I am safe that there is people there who would review cheers your leaf of balance and would offer the suggestions to fit to the relative forces and the weakness of the several ships and classes of the ship. Surely that also would offer the suggestions for the ships you do not have in the balance leaf. A thing that I have noticed is the deficiency of the increase of the defense of the AA for the WWII ships. There is one differentiates great in the capacities from defense 1940 of the AA with respect to 1943 and to 1945. People in Steelnavy can ayudarte with that

Yeah....I know, I have too much free time for my own good.

[Curtis Lemay]

ORIGINAL: Erik Nygaard

Here's a zipped Excel-5 sheet with a bunch of additional ship classes.
I've used Bob's original with a few slight changes.
There are a lot of ship classes not classified in WITP
so I've used the various 'All the World's Fighting Ships' books published by Conway as my main source.
The WITP 'duration' classification is a subjective one, I've taken the normal displacement/280 for other ships,
this to make Warspite the default as Bob did.

Great job, Erik!

By the way, it's "Durability", not "Duration". It certainly does seem subjective. And wherever I didn't have a WitP value (any German, Italian, or Soviet vessel), I just took a blind guess. If there is a systematic way to calculate it, the WitP board would be the place to find out. I may post a question there about it.

Users should note that they still might like to get both my and Erik's spreadsheets to have all the posted class designs, since his lacks several that were on mine, and even where they overlap, we've often reached slightly different results.

[Curtis Lemay]

ORIGINAL: rhinobones
One thing I have noticed is the lack of upgrading of AA defense for the WWII ships. There is a big difference in the capabilities of 1940 AA defense as compared to 1943 and 1945.

Absolutely, which is why I had dates for each class (columns M & N). I built the US & Japanese classes, especially, with their latest WitP dates, since they were for my Okinawa scenario.

[Curtis Lemay]

ORIGINAL: Curtis Lemay
By the way, it's "Durability", not "Duration". It certainly does seem subjective. And wherever I didn't have a WitP value (any German, Italian, or Soviet vessel), I just took a blind guess. If there is a systematic way to calculate it, the WitP board would be the place to find out. I may post a question there about it.

I'm afraid that posting on the WitP board didn't help much. I'd hoped that the original designers would chip in, but all I got was more speculation from other guessers.

Best guesses were that it depends upon things like:

1. Displacement
2. Damage Control teams
3. Pumps
4. Water-tight compartments.

[Erik2]

ORIGINAL: Curtis Lemay
....I'm afraid that posting on the WitP board didn't help much. I'd hoped that the original designers would chip in, but all I got was more speculation from other guessers.

Best guesses were that it depends upon things like:

1. Displacement
2. Damage Control teams
3. Pumps
4. Water-tight compartments.

At least I wasn't too far off using displacement. The other info is a bit harder to find...

[Curtis Lemay]

ORIGINAL: Erik Nygaard

ORIGINAL: Curtis Lemay
....I'm afraid that posting on the WitP board didn't help much. I'd hoped that the original designers would chip in, but all I got was more speculation from other guessers.

Best guesses were that it depends upon things like:

1. Displacement
2. Damage Control teams
3. Pumps
4. Water-tight compartments.

At least I wasn't too far off using displacement. The other info is a bit harder to find...

Yes, most of the other factors would tend to be proportional to displacement, after all. There are exceptions, though, so, when I had a WitP durability figure, I prefered that over any displacement-based value.

[Erik2]

Some more ships, mainly Italian and French.

[akdreemer]

Just some observations and possible corrections

ORIGINAL: Curtis Lemay

Now that we have an equipment editor, we don't have to restrict ourselves to the generic ship classes that come with TOAW. We can create our own. Those of you that read my "How
To..." article on the BioEd may have noticed that I've created a suite of ship classes for my coming update to my Okinawa 1945 scenario. (I've also detailed ship classes for updates to CFNA, France 1944, and Soviet Union 1941, as well).

I thought I would share my method for this (not that it is necessarily the optimum method - that can be a discussion issue here). I've attached the spreadsheet I used to calculate the various parameters.

Note that the data (whenever possible) came from WitP. If you've got WitP, just open the editor and search the classes therein. In some cases, I had to find data on the web.

The formulas I used were as follow:

AP_main = (Relative rate of fire X # main guns X Effect) for the main armament.
AP_secondary = (Relative rate of fire X # secondary guns X Effect) for the secondary armament.
AP_tertiary = (Relative rate of fire X # teritary guns X Effect) for the tertiary armament.

AP_total = (AP_main + (range of secondary)**2/(range of main)**2 X AP_secondary + (range of tertiary)**2/(range of main)**2 X AP_tertiary)/22.67.

Note that secondary and tertiary batteries were only counted if they were not pure AAA guns. Also note the 22.67 scale factor. That was used to make the AP of the Warspite match the generic battleship AP - I arbitrarily set the Warspite as the base standard.

The AP*8 value is necessary for BioEd.

DF = 1.53*(2XDurability + (0.25XDeck Armor + 0.5XBelt Armor + 0.1XTower Armor + 0.15XTurret Armor))

Note that the 1.53 scale factor was again selected to make the Warspite DF match the genereic battleship.

Additonally, DF is also multiplied by an additional factor for ship size/agility.
For BBs/BCs/Monitors, it's 1.
For CAs it's 1.25.
For CLs/CLAAs it's 1.5.
For DDs/DEs it's 3.0

AAA factors are just the sum of AAA ratings (from TOAW) of the AAA or DP guns.

Shell(weight) is derived from Effect (pounds to Kgs).

Km (Range) is a conversion of the WitP "Range" parameter from thousands of yards to km.

Relative rate of fire is relative to the rate of fire of the Warspite. Note that for naval guns, the WitP Accuracy parameter actually is rate of fire.

Note that, since these values will primarily be used for shore bombardment rather than ship to ship combat, I didn't include AP values for torpedos, just guns.

Edit: deleted the attachment to avoid confusion with a subsequent version posted below.

For Gun ranges simply multiply by .91 to convert yards to meters (36in/39.4in).

For final range value for TOAW data multiply primary fun range x 2 then divide x 3. Ensure that extended range is enabled. This change will attenuate the effects of the secondary/tertiary AP values by halving the AP value at longer ranges (last 1/3 range) where these guns cannot fire, thus their AP factors should not be counted at these reanges.

[vahauser]

Rating naval units can get extremely complicated very quickly.  So many variables, so many factors to consider.
 
Let's take one example.  Gun power.  To calculate gun power you need:  rounds of ammo carried per gun, shell penetration data (both horizontal and vertical) for a spectrum of combat ranges, rate of fire (not at important as you might think), type of fire control (centralized? non-centralized? etc.), type of range finding (radar? stereoscopic? etc.), shell weight, crew training and experience, firing arcs (mounted on centerline? other?), and probably some other data that I can't think of off the top of my head.
 
Then, once you have gathered the data you need, you then must create formulae that work.  This is very difficult.  For instance, I mentioned above that rate of fire isn't as important as you might think.  Why not?  Because it takes a certain amount of time for a shell to travel to its target (a shell that has an initial muzzle velocity of 2500mps might take nearly a minute, or more, to travel 30,000m due to the ballistic curve it follows to get to the target (it's not traveling in a straight line at a constant speed)).  Then it takes time to analyze the results of the salvo.  Then it takes time to make corrections for the next salvo.  Then, depending on the type of fire control used, it takes time to order and execute the next salvo.  Thus, for example, even if a big gun has a rate of fire of, say, 2 rounds per minute, that rate of fire is never practically achieved in combat.  Indeed, a well-trained and experienced crew might be doing good to get off a salvo every 90 seconds (at 30,000m) instead of the 30 seconds (2 rounds per minute) that the gun is theoretically capable of.  And this means that simply taking 2 rounds per minute and applying that to a gun-power formula without any modifications (as described above) is going to produce gun-power ratings far greater than what the gun could effectively achieve in actual combat.  And this is just one relatively simple example.
 
I'm not saying that naval units can't be rated, but I am saying that rating naval units is not simple and involves many variables (some of which are highly inter-related).

[Curtis Lemay]

ORIGINAL: AlaskanWarrior

Just some observations and possible corrections

For Gun ranges simply multiply by .91 to convert yards to meters (36in/39.4in).

My figures had the yards corrected to meters (and the pounds corrected to kilograms, etc.).

For final range value for TOAW data multiply primary fun range x 2 then divide x 3. Ensure that extended range is enabled. This change will attenuate the effects of the secondary/tertiary AP values by halving the AP value at longer ranges (last 1/3 range) where these guns cannot fire, thus their AP factors should not be counted at these reanges.

My judgement was that halving the AP at full range was too much. Far more than half the AP strength was usually in the main battery. Instead, the way I modeled it was to calculate average performance. The secondary battery only added a fraction of its strength relative to its area of coverage vs. the area of coverage of the main battery. On average, with the ship operating at random ranges, this gives a reasonable average strength value.

[Curtis Lemay]

ORIGINAL: vahauser

Rating naval units can get extremely complicated very quickly.  So many variables, so many factors to consider.

Let's take one example.  Gun power.  To calculate gun power you need:  rounds of ammo carried per gun, shell penetration data (both horizontal and vertical) for a spectrum of combat ranges, rate of fire (not at important as you might think), type of fire control (centralized? non-centralized? etc.), type of range finding (radar? stereoscopic? etc.), shell weight, crew training and experience, firing arcs (mounted on centerline? other?), and probably some other data that I can't think of off the top of my head.

Crew training and experience would be modeled by the unit proficiency. For the other factors, remember that TOAW doesn't actually simulate the launch of shells, their flight to the target, and their impact on the target. It just has an AP value. That's going to be more or less relative.

Then, once you have gathered the data you need, you then must create formulae that work.  This is very difficult.  For instance, I mentioned above that rate of fire isn't as important as you might think.  Why not?  Because it takes a certain amount of time for a shell to travel to its target (a shell that has an initial muzzle velocity of 2500mps might take nearly a minute, or more, to travel 30,000m due to the ballistic curve it follows to get to the target (it's not traveling in a straight line at a constant speed)).  Then it takes time to analyze the results of the salvo.  Then it takes time to make corrections for the next salvo. 

All that is done with multiple shells in the air. They don't just fire one shell, wait for it to land, calculate the corrections, and only then launch the next shell. They fire more or less as fast as they can and keep track of all the shells - many of which are from different guns and even different ordinances.

Then, depending on the type of fire control used, it takes time to order and execute the next salvo.  Thus, for example, even if a big gun has a rate of fire of, say, 2 rounds per minute, that rate of fire is never practically achieved in combat.  Indeed, a well-trained and experienced crew might be doing good to get off a salvo every 90 seconds (at 30,000m) instead of the 30 seconds (2 rounds per minute) that the gun is theoretically capable of.  And this means that simply taking 2 rounds per minute and applying that to a gun-power formula without any modifications (as described above) is going to produce gun-power ratings far greater than what the gun could effectively achieve in actual combat.  And this is just one relatively simple example.

I expect that the values in WitP were effective rates, not some theoretical maximum. Regardless it would be true for all guns, so the relative values will be more or less right. Again, TOAW isn't simulating shell flight & etc.

[vahauser]

Curtis Lemay[/b],
 
All I am saying is that there are factors and variables that need to be accounted for correctly if the final rating is going to be an accurate reflection of that naval unit's historical combat capabilities in terms of TOAW.
 
You state that ships fired while they still had shells in the air.  In some cases I agree (antiaircraft, for instance), but in other cases I disagree.  For example, the Yamato had an orange-red die in their shells to mark the shell splashes.  There is no point in having colored die in the shells unless the shells are being spotted and corrected for before the next salvo is fired. 
 
But even if you want to argue this fact, there is an absolute limit to gun performance and that limit is ammo supply.  The Yamato carried somewhere around 80-120 shells per gun (and not all of those rounds would be armor piercing).  Let’s say that the Yamato carries 100 rounds per gun and 75 of those are armor piercing.  Now, in a game turn that lasts anywhere from several hours to several days, the Yamato can easily fire all of its armor piercing ammo in a single turn.  So, once again, the theoretical rate of fire of the Yamato’s guns is basically insignificant since ammo supply is limited.  Therefore, any formula that puts a lot of emphasis on rate of fire is going to produce results that are out of calibration with TOAW’s game scale (i.e., inaccurate and unrealistic).  Instead, given TOAW’s game scale, ammo supply is WAY more important than rate of fire (in terms of being useful for TOAW).  And I don’t know how WitP handled RoF vs. ammo supply in its calculations.  But the ratings you posted earlier in this thread seemed “off” in this regard.
 
Anyway, I believe that in terms of TOAW’s game scale, the most important factors that matter for gun performance ratings (and not counting antiaircraft since that should be calculated differently, only talking surface to surface gunfire here) are:
 
Crew training and experience (already taken care of by TOAW’s proficiency ratings)
Fire control and rangefinding (i.e., accuracy)
Ammo supply
Shell weight (weight of AP round)
Shell penetration (horizontal and vertical)
Effective range (and not maximum range)
 
Additional modifiers that could be applied:
A “scaled down” modifier for rate of fire
A modifier for firing arcs
[font="times new roman"] [/font]

[Curtis Lemay]

ORIGINAL: vahauser
You state that ships fired while they still had shells in the air.  In some cases I agree (antiaircraft, for instance), but in other cases I disagree.  For example, the Yamato had an orange-red die in their shells to mark the shell splashes.  There is no point in having colored die in the shells unless the shells are being spotted and corrected for before the next salvo is fired. 

Disagree all you want. You'll still be wrong. They kept track of multiple shells in the air. They had to. Otherwise, only one gun on one ship could be fired per 2-3 minutes. Admittedly, things could get really complicated if you've got several ships with multiple guns of different sizes firing. But that's war. The spotting and correcting was still done, but the waiting was omitted. So, maybe shell number 5 was corrected for the results of shell number 1, etc.

Think of a garden hose. Can you keep the garden hose on your dog as he runs around? Or do you have to fire off a drop at a time, then wait for each drop to hit before launching another?

But even if you want to argue this fact, there is an absolute limit to gun performance and that limit is ammo supply.  The Yamato carried somewhere around 80-120 shells per gun (and not all of those rounds would be armor piercing).  Let’s say that the Yamato carries 100 rounds per gun and 75 of those are armor piercing.  Now, in a game turn that lasts anywhere from several hours to several days, the Yamato can easily fire all of its armor piercing ammo in a single turn.  So, once again, the theoretical rate of fire of the Yamato’s guns is basically insignificant since ammo supply is limited.  Therefore, any formula that puts a lot of emphasis on rate of fire is going to produce results that are out of calibration with TOAW’s game scale (i.e., inaccurate and unrealistic).  Instead, given TOAW’s game scale, ammo supply is WAY more important than rate of fire (in terms of being useful for TOAW).  And I don’t know how WitP handled RoF vs. ammo supply in its calculations.  But the ratings you posted earlier in this thread seemed “off” in this regard.

TOAW handles supply issues. This is no different than for any other piece of artillery. Ship-to-ship engagements don't last too long. Long term ground support would see the ships being resupplied at sea, but TOAW models their lower fire rates as ammo gets scarce (their combat strength drops with supply level).

Anyway, I believe that in terms of TOAW’s game scale, the most important factors that matter for gun performance ratings (and not counting antiaircraft since that should be calculated differently, only talking surface to surface gunfire here) are:

Crew training and experience (already taken care of by TOAW’s proficiency ratings)
Fire control and rangefinding (i.e., accuracy)

Also handled by proficiency ratings.

Ammo supply

Handled by TOAW's supply system.

Shell weight (weight of AP round)
Shell penetration (horizontal and vertical)
Effective range (and not maximum range)

I used those, or similar. Shell weight and shell penetration tend to be proportional.

Additional modifiers that could be applied:
A “scaled down” modifier for rate of fire

And rate of fire. No scaling down.

A modifier for firing arcs

How? All we can end up with (at this time) is a single AP value.

[vahauser]

Curtis Lemay[/b],
 
35 years ago, around the time I first started to play naval minatures, the first naval wargame I played was called "Fletcher Pratt's Naval Rules" (or something like that).  You might want to see if you can find that game since it gave 'aggregate total' ship ratings for defense and offense very similar to what you are trying to achieve.
 
25 years ago, I started playing a newer set of naval miniatures called “Seapower”.  This was a more detailed and accurate modeling of naval warfare.  Seapower gave more complete naval ratings compared to Fletcher Pratt.
 
15 years ago, I worked for GR/D as a designer/developer for their Europa boardgame series (mainly air system, but kept my fingers in the naval pie too, so to speak).  After my time at GR/D, I worked for Pacifica Games as the primary developer, and not only shaped the naval system, but rated the naval units as well.  The past several posts I have been drawing from memory.  But I think I have a box or two of data and calculations regarding naval units and naval ratings gathering dust in the garage or attic or somewhere.  I will try to find those boxes and dig through them to see if I can help you.
 
P.S.  So sorry if you want to believe that the Bismark or Hood or Yamato (etc.) fired salvos while previous salvos were still in the air.  No ship commander I’ve ever heard of would ever order such a thing except under one condition:  if they had a helpless sitting-duck target that they had already zeroed, then they might, maybe, conceivably order such a thing.  But in actual combat under variable sea and weather conditions against an enemy who is still maneuvering and fighting back?  So sorry.  Anyway, I’ll try to find those boxes of data. . .

[ColinWright]

ORIGINAL: Curtis Lemay
Think of a garden hose. Can you keep the garden hose on your dog as he runs around? Or do you have to fire off a drop at a time, then wait for each drop to hit before launching another?

Hmm. Where do you live? I need to contact your local SPCA about this...

[ColinWright]

TOAW handles supply issues. This is no different than for any other piece of artillery. Ship-to-ship engagements don't last too long. Long term ground support would see the ships being resupplied at sea, but TOAW models their lower fire rates as ammo gets scarce (their combat strength drops with supply level).

Well, let's face it: the TOAW supply model really sucks when it comes to artillery-type weapons -- like ships. Their rate of fire should stay the same until they burn off their shells: then drop abruptly to zero. You don't want this to happen, stop firing.

It's not like infantry, where you can indeed begin conserving ammunition, bring up a few cases of ammo somehow, tell the machine-gunner to fire only if there's a concerted attack, etc. Artillery uses its shells and it should become useless. Might as well have big pieces of agricultural machinery standing around...

[Curtis Lemay]

ORIGINAL: vahauser

Curtis Lemay[/b],

35 years ago, around the time I first started to play naval minatures, the first naval wargame I played was called "Fletcher Pratt's Naval Rules" (or something like that).  You might want to see if you can find that game since it gave 'aggregate total' ship ratings for defense and offense very similar to what you are trying to achieve.

25 years ago, I started playing a newer set of naval miniatures called “Seapower”.  This was a more detailed and accurate modeling of naval warfare.  Seapower gave more complete naval ratings compared to Fletcher Pratt.

15 years ago, I worked for GR/D as a designer/developer for their Europa boardgame series (mainly air system, but kept my fingers in the naval pie too, so to speak).  After my time at GR/D, I worked for Pacifica Games as the primary developer, and not only shaped the naval system, but rated the naval units as well.  The past several posts I have been drawing from memory.  But I think I have a box or two of data and calculations regarding naval units and naval ratings gathering dust in the garage or attic or somewhere.  I will try to find those boxes and dig through them to see if I can help you.

I've got plenty of board naval wargames with agregate ratings of such as well. But I figure the WitP data are better. And it doesn't sound like any of those were simulators.

Have you ever heard of "Task Force 1942"? It was a DOS-based simulator of the Guadalcanal campaign. It actually allowed you to sit in the ships fire control, and fire the guns. (You could also forgo that and just function as the Task Force commander.) The shells' trajectories were then actually simulated all the way to the target. There was a "computer" you could turn on that gave you a recommended transom and elevation. It's accuracy inproved as more and more shells came close to the target. But it would then lower its accuracy as the target changed course, etc. Clearly, the "computer" would represent the end product of trackers following each shell, noting its effect, and figureing a correction accordingly. There were (it was Guadalcanal after all) plenty of other guns and ships firing on both sides. The sky would be full of shell trajectories. Other ships and guns were controlled by the game's AI.

Note that those AI controlled guns didn't wait for the shells to land and corrections to be made before firing again. They fired as fast as possible.

P.S.  So sorry if you want to believe that the Bismark or Hood or Yamato (etc.) fired salvos while previous salvos were still in the air. 

Thanks, I will.

No ship commander I’ve ever heard of would ever order such a thing except under one condition:  if they had a helpless sitting-duck target that they had already zeroed, then they might, maybe, conceivably order such a thing.  But in actual combat under variable sea and weather conditions against an enemy who is still maneuvering and fighting back?  So sorry.  Anyway, I’ll try to find those boxes of data. . .

If so, that could account for why those three ships were all sunk. If you're going to fire one shell for each three your target is firing back at you, you had better prepare to swim! The corrections are transient anyway (as the ships maneuver), and improve with more data.

[Curtis Lemay]

ORIGINAL: ColinWright

ORIGINAL: Curtis Lemay
Think of a garden hose. Can you keep the garden hose on your dog as he runs around? Or do you have to fire off a drop at a time, then wait for each drop to hit before launching another?

Hmm. Where do you live? I need to contact your local SPCA about this...

Alright. Correction: Can you keep the garden hose on your wife as she runs around?