Feasibility Study - Fuel based Upkeep

[Nobody]

In its most basic form a fuel based upkeep requires only 3 numbers to be copied from SpringSharp: cruise speed, range and maximum bunker size. The basic formula then is
   max_bunker_size / range * cruise_speed
which is fuel consumption per hour. All that's left would be scaling that to our need.

Due to their high fuel consumption, special destroyer rules would be unnecessary.



In N3 ships were in 1 of 3 states of readiness, explained (from memory) as:

• mobilized: a ship in active service which spends almost 100% of its time at sea
  
• active: a ship in service spending about 40% of its time at sea - mostly training. Can react to emergencies within a days
  
• reserve: a ship which is kept in working oder, but takes weeks (months) to be ready for action
  This definition could act as a nice multiplier to upkeep cost.
  
  Now assuming ship also have a constant cost (based on size or crew) I propose:
  
• mob: full or slightly(10-25%) increased crew cost, full fuel cost
  
• active: full crew cost, 40% fuel cost
  
• reserve: ~30% crew cost, 5% fuel cost (heating)
  
  
  
  Especially in war times ships will often go much faster than cruise speed. Therefore I propose to add a ships maximum speed into the equation. Fuel consumption at full speed is increased by a factor of   (v_max/v_cruise)^3   over cruise speed.
  My proposal would be to use a different "speed mix" whether you're at war or not, e.g.:
     peace: 90% cruise and 10% top speed
     war: 60% cruise and 40% top speed
  
  
  Examples
  Except for the first one, I borrowed KWorld's most recent USN designs
  NOTE: this table contains a lot more information than needed for my proposal!
  
  

  	displacement									Fuel consumption			speed mix
  	light	standard	normal	full load	max speed	cruise speed	range	max bunker size		cruise speed	v_max		peacetime	wartime
  battleship	16631	17383	18434	19275	22	12	4000	1892	per hour	5,68	34,98		8,61	17,4
  									per day	136,2	839,4		207	418
  									per month	4087	25183		6196	12525
  									per quarter	12439	76649		18860	38123
  									per term	16585	102199		25147	50831
  USS Smith	617	640	742	823	29,5	15	2000	183	per hour	1,37	10,44		2,28	5
  									per day	32,9	250,6		55	120
  									per month	988	7517		1641	3600
  									per quarter	3008	22879		4995	10956
  									per term	4010	30506		6660	14609
  USS Arkansas	2676	2852	3074	3251	12,5	10	3000	400	per hour	1,33	2,6		1,46	1,84
  									per day	32	62,5		35,1	44,2
  									per month	960	1875		1052	1326
  									per quarter	2922	5707		3201	4036
  									per term	3896	7609		4267	5381
  USS Omaha	3971	4132	4837	5400	27	12	6000	1269	per hour	2,54	28,91		5,18	13,09
  									per day	60,9	693,8		124,2	314,1
  									per month	1827	20815		3726	9422
  									per quarter	5562	63355		11341	28679
  									per term	7416	84473		15122	38239
  USS Montana	14811	15544	17198	18521	25	12	6500	2977	per hour	5,5	49,7		9,92	23,18
  									per day	131,9	1192,7		238	556
  									per month	3957	35781		7140	16687
  									per quarter	12044	108909		21731	50790
  									per term	16059	145212		28975	67720
  USS Connecticutt	12819	13588	14695	15580	18	10	6600	1993	per hour	3,02	17,61		4,48	8,86
  									per day	72,5	422,7		107,5	213
  									per month	2174	12680		3225	6376
  									per quarter	6618	38594		9815	19408
  									per term	8824	51459		13087	25878

  Now please take a look at the table and notice that (for larger ships) displacement and (term/quarter speed mix) fuel consumptions are int the same order of magnitude.
  
  Conclusion
  I think a fuel based upkeep is possible, interesting and worth the effort. I think the follwing numbers would work (assuming money is scaled up accordingly):
  
• Base or Crew cost: 1$ per 1000 tons of a ship normal or maximum displacement
  
• Fuel cost: 1$ per 1000 tons of fuel a ship need per term/quarter. Adjusted for readiness and wartime usage.
  
• (Ammo cost? War-time only. Mainly steel.)
  
• (Build cost: $ on normal, steel on standard)

[Jefgte]

Interresting work Nobody.

Are you going to made an excel board calculator for speed/fuel/range ?

Actualy, I use directly SS to calculate the possible range.
I note the bunkerage in ton & change the cruise speed.

I know that with 5000nm@ 12kts, the range is more than 7500nm@ 10kts.
Interresting for the transfer of ships to the colonies...

Jef  ;)

[snip]

My first thoughts:

Conclusion
I think a fuel based upkeep is possible, interesting and worth the effort. I think the follwing numbers would work (assuming money is scaled up accordingly):

• Base or Crew cost: 1$ per 1000 tons of a ship normal or maximum displacement
  
• Fuel cost: 1$ per 1000 tons of fuel a ship need per term/quarter. Adjusted for readiness and wartime usage.
  
• (Ammo cost? War-time only. Mainly steel.)
  
• (Build cost: $ on normal, steel on standard)
  

I like the manor in which this is presented.  I feel that upkeep and all constructions costs should be calculated from Normal tonnage, no more no less. However, adding on a upkeep cost on fuel is something the community could look at. It is consisse enough that I don't feel it would add to much complexity to the naval side of the rules. Naval rules are the one place that I feel we can safely abandon some aspects of simplicity for the sake of a more realistic system. I do not however want to add ammo upkeep. With regards to construction costs, I would like normal displacment to be the defining factor for both the $ cost and industrial cost. What thoughts do others have?

[Jefgte]

Attention to the complexity of the rules!

How do you calculate the cost of moving a squadron of 5000km.
Fuel, refueling, food (.. & wine for French)

Keep it simple, if you add a cost of movement apply just a draft ratio proportional to the size of the vessel.


;)

[KWorld]

Myself, I think the construction cost of a ship should either be the SS3 $ cost of the ship OR (if we're using a tonnage-based system) something based on the ship's light displacement..  Why light displacement vs normal displacement?  Because light displacement is the tonnage of the ship itself, the other displacements that SS3 calculates include consumables, which will be paid for as part of the ships maintenance.

[Nobody]

How do you calculate the cost of moving a squadron of 5000km.
Fuel, refueling, food (.. & wine for French)

I would switch them to mobilized for the turn of moving. Or longer if necessary.

[Delta Force]

My first thoughts:

Conclusion
I think a fuel based upkeep is possible, interesting and worth the effort. I think the follwing numbers would work (assuming money is scaled up accordingly):

• Base or Crew cost: 1$ per 1000 tons of a ship normal or maximum displacement
  
• Fuel cost: 1$ per 1000 tons of fuel a ship need per term/quarter. Adjusted for readiness and wartime usage.
  
• (Ammo cost? War-time only. Mainly steel.)
  
• (Build cost: $ on normal, steel on standard)
  

I like the manor in which this is presented.  I feel that upkeep and all constructions costs should be calculated from Normal tonnage, no more no less. However, adding on a upkeep cost on fuel is something the community could look at. It is consisse enough that I don't feel it would add to much complexity to the naval side of the rules. Naval rules are the one place that I feel we can safely abandon some aspects of simplicity for the sake of a more realistic system. I do not however want to add ammo upkeep. With regards to construction costs, I would like normal displacment to be the defining factor for both the $ cost and industrial cost. What thoughts do others have?

I think construction costs should be calculated using light tonnage, as it includes all of the equipment needed to have a functional ship. If you want the ship to go into duty you should have to purchase the ship's first ammunition load (using industrial output) and fuel (using cash), but if it is going straight into the reserves you don't really need that. Upkeep should be a mix of industrial output for the ammunition and cash for the fuel, with additional industrial output upkeep related to light tonnage (hull upkeep) and cash related to crew size (for crew pay).

[snip]

Construction costs: Normal tonnage is preferable to light due to the manor in which ships of almost identical hulls can have vast differences in construction cost based on range. Normal displacement is consistant between all designs regardless of range. Upkeep will be based on normal displacement and maybe fuel use if we can agree on how to implement it. I dont want to pay seperate upkeep for ammunition and crew salary. That is just to complex IMO.

[KWorld]

Sure, light displacement can vary drastically based on the ships' range, but that's the point of paying LIGHT for construction and NORMAL for maintenance: that the long-ranged ship (a higher-percentage of it's normal displacement is essentially empty fuel tanks or bunkers) doesn't get ripped off in it's construction costs by having to pay a lot for empty space that doesn't cost much to include.

[Delta Force]

Sure, light displacement can vary drastically based on the ships' range, but that's the point of paying LIGHT for construction and NORMAL for maintenance: that the long-ranged ship (a higher-percentage of it's normal displacement is essentially empty fuel tanks or bunkers) doesn't get ripped off in it's construction costs by having to pay a lot for empty space that doesn't cost much to include.

Exactly, otherwise a cruiser and a monitor of the same size cost the same amount to build, even if the cruiser is mostly fuel tanks and the monitor is a massive armored ship.

[snip]

This was a change made for N4 by people with much greater knologe of the program then me. I feel that keeping it accounts for the initial filling out of stores, ammunition and other consumable. Upkeep then covers the replacement and replenishment of these initial stores. Does that make sense?

[Logi]

It was my impression that we made the change for several reasons unrelated. One such reason was that it was easily to set a defined limit to the ship weight (by input) and thus avoid ugly BP spending. Another was that it was felt that using light tonnage allowed gaming the system - that is - you could build a ship and increase various parameters of the ship (like steadiness, etc.) whilst keeping the BP cost down by making the ship larger but using the weight for bunker size.

If we make maintenance normal displacement-based than we eliminate the latter problem but keep the former.

[Delta Force]

This was a change made for N4 by people with much greater knologe of the program then me. I feel that keeping it accounts for the initial filling out of stores, ammunition and other consumable. Upkeep then covers the replacement and replenishment of these initial stores. Does that make sense?

I think we should have heavy industry goods (like artillery shells, armor, ships) use industrial capacity while light industry goods (such as fuel, staterooms on passenger liners) use cash. If you pay for fuel and other light industry goods with industrial capacity (by paying for ships at normal tonnage) it is hurting the ability of long ranged navies (like the French and British) to expand their fleets in the short term while giving the smaller fleets an advantage as they use less fuel. That means the Austro-Hungarians can build a floating fortress bristling with guns and armor and the Italians can build a ship build for longer range and having less armor and they will pay the same (assuming same normal tonnage) even though the Austro-Hungarian ship would be more expensive to build.

If instead you make it more expensive to build those floating fortresses (high short term costs) and make it more expensive to operate the fuel guzzling ships you make it more fair and more interesting. Someone might decide to go the USN route and use triple expansion engines instead of turbines for their long range ships to save on fuel costs, for example. If you pay just based on tonnage (light or normal) there is no reason not to go for turbines because past 1905 the engines and their fuel weigh less than triple expansion engines even though they burn a lot more fuel for a given output.

[snip]

Once again, I think the change to normal displacement for N4 was to minimize gaming of SS in order to gain an advantage. This change was made be people who have much more experience with both SpringSharp and the sim overall then I do. I would like to keep that in mind when deciding what to use.

[KWorld]

Where WesWorld gets in trouble with using light vs normal displacement is that there there's no maintenance costs at all other than refits, which are again based on light displacementl.  So there, there's an incentive to game SS by installing extra-large fuel tanks, which improve the ship but don't cost anything.  If we base maintenance costs  on normal or maximum displacement,  we won't have that problem: if you over-size your ship, you'll get to pay, and pay, and pay, for doing so.