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Ducimus · 12-17-11, 06:10 PM

Ok, not sure where to post this, but this thread seems as good a spot as any since my brain has just turned to mush.

-------------------------------------
Regarding Point A to point B distances:
-------------------------------------

Real World Navigation
From the mouth of Pearl Harbor, to the mouth of Tokyo bay, the distance, in the real spherical world is 3,346 NM.

Game World Navigation
From the mouth of Pearl Harbor, to the mouth of Tokyo bay, the distance, in the virtual flat world is 4,129 NM.

The difference from Real to Game:
If you multiply the real world point A to point B distance of 3346 by 23% (0.234 to be exact), you get the result of 4128.964, which very closely match's the distance measured from the exact same two points in game.

Therefore, the game world is 23% larger then in real life.

-----------------
Regarding Fuel:
-----------------

Using the Gato class as a benchmark, the following is my best extrapolation based on all resources available to me. (meaning a whole lot of web and forum searching)

Standard Fuel Capacity:
Reputable sources agree that the original design for the Gato Class Submarine carried 94,400 gallons of fuel oil in it's oil tanks. The oft cited and accepted statistic for the resulting range of said 94,400 gallons of fuel oil is 11,000 NM @ 10 knots.

Extended Fuel Capacity:
Later on at a date i was unable to find, the original design of the Gato class was modified. Several ballast tanks were modified so they could be used to carry fuel, further extending the fuel capacity of the Submarine. Sources agree to total fuel capacity being 116,000 gallons with fuel ballast tanks. (Henceforth referred to as "FBT")

Reiteration of Fuel capacity:
Nominal fuel carried: 94,400 gallons
Maximum fuel carried via FBT: 116,000 gallons

Total fuel extension over original design: 21,600 gallons.

Extrapolation:

- Of standard fuel capacity
If

commonly accepted figure of 11,000 NM @ 10 knots is accurate

Then

94,400 gallons divided by 11,000 NM = 8.58 gallons of fuel used per mile.

- Of Extended fuel capacity
Then if

8.58 Gallons of fuel is used per mile

8.58 divided by 21,600 gallon contained in the FBT = 2,541 NM

- Therefore:

11,000 NM + 2,541 NM = 13,541 NM. Or in other words, our Gato, could, in a real spherical world, travel a distance of 13,541 NM @ 10 knots

New Translation of Real world into Game world:

Increasing endurance, within scale of the game world.

If

Real world endurance 13,541 NM, multiplied by 23% map sized increase for flat map projection in game.

13,541 * 0.234 = 3,158.59

Or in other words, our gato's endurance with extended fuel should be 3,158.59 NM more to account for the flat map.

Then

Real world range with FBT ( 13,541 NM ) plus the 23% increase of distances (3,158.59), equals 16699.59.
or simply put, in game, a Gato should have 16,700 NM @ 10 knots.

-----------------------------------------------------
Problems with the game Engine and Historical accuracy
-----------------------------------------------------

Problem with Game Engine

Problem No1:
Diesel engine fuel efficiency is not modeled correctly, nor is it possible to alter it.

Problem No 2:
The game is hardcoded on how it handles fuel usage. Regardless of what you enter speed and range. It is, at it's heart, a Uboat sim. Certain aspects continue to reflect this. As fuel usage goes, this means:

a.) Going slower then 9 to 10 knots is always fuel inefficient.

b.)Going 9 to 10 knots is always, (approximately) 2.12 times more fuel efficient regardless of what specify, if above 10 knots.

Historical Problems when applied to the game engine:

- The game does not provide a method of putting X number of engines on battery recharge or propulsion.

- Fleet type submarines, were originally designed to run with the surface fleet. They were capable of cruising at speeds greater then 10 knots when surfaced. Various patrol reports and non fictional books and/or first hand accounts would collaborate this. Most patrol reports will cite entries such as "two engine speed" or "three engine speed".

A little known fact as it pertains to battery charging in game:

Battery recharge times will vary according to your surface speed. While the game provides no direct method of putting X number engines on the battery charge, it is implied.

Assuming the telegraph settings are modified as thus:
* Ahead 1/3rd is 25% of your engines
* Ahead 2/3rds is 50% of your engines
* Ahead standard is 75%
* Ahead Full is 90%
* Ahead Flank is 100%

For the purposes of fuel expenditure, surface cruising, and battery recharging, this means:

- at 1/3, you have 3 engines on the charge, and 1 on propulsion. This could be called, "one engine speed". Assuming a top speed of 20 knots, one engine speed is 5 knots.

- At 2/3rd, you have 2 engines on the charge, and 2 on propulsion. This could be called, "two engine speed". Assuming a top speed of 20 knots, two engine speed is 10 knots.

- at Standard, you have 1 engine on the charge, and 3 on propulsion. This could be called, "three engine speed". Assuming a top speed of 20 knots, three engine speed is 15 knots.

In the game, you will notice a direct correlation between, how long the battery takes to charge, and how fast your going on the surface.

-------------------------------------------
TMO Specific: New fuel settings in TMO 2.5:
------------------------------------------

Long story short, A picture is worth a 1000 words:

The above picture, i feel is the best balance between how the game engine behaves, and historical concerns.

Explanation using Gato as an example.
Gato at 75% throttle (ahead standard) is 15 knots. For a Gato, this is 3 engine speed.

In the submarines .sim file, I will have specified 8700 NM @ 15 knots. If you examine that figure, that means you have 4,000 NM range. (round trip 8,000) If you leave pearl harbor at ahead standard, you'll get about as far as Lots wife and back, with a remaining 700 NM @ 15 knots for patrolling.

- If while on patrol, you reduce your speed to two engine speed, (2/3rds or 10 knots), that 700 NM distance becomes 1470 NM that you can allot to patrolling your general area. Now assuming you were to travel in a straight line, that distance is enough to get you from Lots wife, to the NW corner of Luzon.

OR,

- if your insistent on doing 2/3rds the whole way (Would you think outside the Uboat box already!

), you'll be getting about 18,400 NM range, which is a fudging of 1700 NM. Far from perfect, but far closer to the more realistic 16,700 NM then the current 29,000 NM your getting now im TMO 2.2

In TMO 2.2 I had adjusted the speed on the assumption of a standard cruising speed of 15 knots. Since actual cruising speeds varied, while cruising at 15 knots is realistic, cruising at 15 knots ALL THE TIME, is not realistic. Furthermore, expecting the player to cruise at Ahead standard all the time, knowing full well they can exploit the games hardcoded design, is also quite unrealistc. Those of you who are playing TMO 2.2 and cruising at two engine speed are quite familiar with the range boost I discussed earlier.

12-17-11, 06:10 PM	#45
Ducimus Rear Admiral Join Date: May 2005 Posts: 12,987 Downloads: 67 Uploads: 2	Ok, not sure where to post this, but this thread seems as good a spot as any since my brain has just turned to mush. ------------------------------------- Regarding Point A to point B distances: ------------------------------------- Real World Navigation From the mouth of Pearl Harbor, to the mouth of Tokyo bay, the distance, in the real spherical world is 3,346 NM. Game World Navigation From the mouth of Pearl Harbor, to the mouth of Tokyo bay, the distance, in the virtual flat world is 4,129 NM. The difference from Real to Game: If you multiply the real world point A to point B distance of 3346 by 23% (0.234 to be exact), you get the result of 4128.964, which very closely match's the distance measured from the exact same two points in game. Therefore, the game world is 23% larger then in real life. ----------------- Regarding Fuel: ----------------- Using the Gato class as a benchmark, the following is my best extrapolation based on all resources available to me. (meaning a whole lot of web and forum searching) Standard Fuel Capacity: Reputable sources agree that the original design for the Gato Class Submarine carried 94,400 gallons of fuel oil in it's oil tanks. The oft cited and accepted statistic for the resulting range of said 94,400 gallons of fuel oil is 11,000 NM @ 10 knots. Extended Fuel Capacity: Later on at a date i was unable to find, the original design of the Gato class was modified. Several ballast tanks were modified so they could be used to carry fuel, further extending the fuel capacity of the Submarine. Sources agree to total fuel capacity being 116,000 gallons with fuel ballast tanks. (Henceforth referred to as "FBT") Reiteration of Fuel capacity: Nominal fuel carried: 94,400 gallons Maximum fuel carried via FBT: 116,000 gallons Total fuel extension over original design: 21,600 gallons. Extrapolation: - Of standard fuel capacity If commonly accepted figure of 11,000 NM @ 10 knots is accurate Then 94,400 gallons divided by 11,000 NM = 8.58 gallons of fuel used per mile. - Of Extended fuel capacity Then if 8.58 Gallons of fuel is used per mile 8.58 divided by 21,600 gallon contained in the FBT = 2,541 NM - Therefore: 11,000 NM + 2,541 NM = 13,541 NM. Or in other words, our Gato, could, in a real spherical world, travel a distance of 13,541 NM @ 10 knots New Translation of Real world into Game world: Increasing endurance, within scale of the game world. If Real world endurance 13,541 NM, multiplied by 23% map sized increase for flat map projection in game. 13,541 * 0.234 = 3,158.59 Or in other words, our gato's endurance with extended fuel should be 3,158.59 NM more to account for the flat map. Then Real world range with FBT ( 13,541 NM ) plus the 23% increase of distances (3,158.59), equals 16699.59. or simply put, in game, a Gato should have 16,700 NM @ 10 knots. ----------------------------------------------------- Problems with the game Engine and Historical accuracy ----------------------------------------------------- Problem with Game Engine Problem No1: Diesel engine fuel efficiency is not modeled correctly, nor is it possible to alter it. Problem No 2: The game is hardcoded on how it handles fuel usage. Regardless of what you enter speed and range. It is, at it's heart, a Uboat sim. Certain aspects continue to reflect this. As fuel usage goes, this means: a.) Going slower then 9 to 10 knots is always fuel inefficient. b.)Going 9 to 10 knots is always, (approximately) 2.12 times more fuel efficient regardless of what specify, if above 10 knots. Historical Problems when applied to the game engine: - The game does not provide a method of putting X number of engines on battery recharge or propulsion. - Fleet type submarines, were originally designed to run with the surface fleet. They were capable of cruising at speeds greater then 10 knots when surfaced. Various patrol reports and non fictional books and/or first hand accounts would collaborate this. Most patrol reports will cite entries such as "two engine speed" or "three engine speed". A little known fact as it pertains to battery charging in game: Battery recharge times will vary according to your surface speed. While the game provides no direct method of putting X number engines on the battery charge, it is implied. Assuming the telegraph settings are modified as thus: * Ahead 1/3rd is 25% of your engines * Ahead 2/3rds is 50% of your engines * Ahead standard is 75% * Ahead Full is 90% * Ahead Flank is 100% For the purposes of fuel expenditure, surface cruising, and battery recharging, this means: - at 1/3, you have 3 engines on the charge, and 1 on propulsion. This could be called, "one engine speed". Assuming a top speed of 20 knots, one engine speed is 5 knots. - At 2/3rd, you have 2 engines on the charge, and 2 on propulsion. This could be called, "two engine speed". Assuming a top speed of 20 knots, two engine speed is 10 knots. - at Standard, you have 1 engine on the charge, and 3 on propulsion. This could be called, "three engine speed". Assuming a top speed of 20 knots, three engine speed is 15 knots. In the game, you will notice a direct correlation between, how long the battery takes to charge, and how fast your going on the surface. ------------------------------------------- TMO Specific: New fuel settings in TMO 2.5: ------------------------------------------ Long story short, A picture is worth a 1000 words: The above picture, i feel is the best balance between how the game engine behaves, and historical concerns. Explanation using Gato as an example. Gato at 75% throttle (ahead standard) is 15 knots. For a Gato, this is 3 engine speed. In the submarines .sim file, I will have specified 8700 NM @ 15 knots. If you examine that figure, that means you have 4,000 NM range. (round trip 8,000) If you leave pearl harbor at ahead standard, you'll get about as far as Lots wife and back, with a remaining 700 NM @ 15 knots for patrolling. - If while on patrol, you reduce your speed to two engine speed, (2/3rds or 10 knots), that 700 NM distance becomes 1470 NM that you can allot to patrolling your general area. Now assuming you were to travel in a straight line, that distance is enough to get you from Lots wife, to the NW corner of Luzon. OR, - if your insistent on doing 2/3rds the whole way (Would you think outside the Uboat box already! ), you'll be getting about 18,400 NM range, which is a fudging of 1700 NM. Far from perfect, but far closer to the more realistic 16,700 NM then the current 29,000 NM your getting now im TMO 2.2 In TMO 2.2 I had adjusted the speed on the assumption of a standard cruising speed of 15 knots. Since actual cruising speeds varied, while cruising at 15 knots is realistic, cruising at 15 knots ALL THE TIME, is not realistic. Furthermore, expecting the player to cruise at Ahead standard all the time, knowing full well they can exploit the games hardcoded design, is also quite unrealistc. Those of you who are playing TMO 2.2 and cruising at two engine speed are quite familiar with the range boost I discussed earlier. Last edited by Ducimus; 12-17-11 at 07:11 PM.