Fuel Consumption and Manual Navigation

[MudMarine]

Skippers,

I am going to practice manual navigation as part of realism. I will be using the Navigation map plot for Noon and midnight Star sightings. Weather permitting. If clear enough skies got to navigation map for longitude and latitude and plot it on a real map. While in patrol areas use area maps.

For this to work I need fuel consumption rates at all speeds for all type boats. I know that fuel is measured from 100%.

I also need to find out what is the best speed to travel on the surface to conserve fuel and have max time on station in patrol areas. This is also by type boat.

I am going to use the max fuel capacity in gallons for each type boat. So does anyone have that data.

I would also like to now how was fuel consumption actual figured in real life and what navigational tool they used to figure this out. I suspect a side ruler. If so what was the formula?

[Convoystalker]

There are several variables that you cant factor into a theoretical range which affect fuel consumption.
1. Damage to motors.
2. Different engine room crews & watches whose skill affects fuel consumption.
3. Stormy weather might ??? not sure.

Easiest way to find out is draw some waypoints from Pearl Harbour or Freemantle towards somewhere that no trouble is expected, note each waypoint distance from start then just do a practice voyage along a straigh line noting how far you get for 25% then 50% fuel in undamaged condition with that crew.

I've noticed that after battle damage there seems to be substantial extra fuel consumption.
For instance from Freemantle to Penang in a Porpoise sailing at 2/3rds = about 11-12knots uses just on 25% but to get back after some damage (that's been repaired) the boat used almost 50% fuel for return voyage !!!!

Overall your most economic cruise setting on any boat is 2/3rds.

[IRONxMortlock]

I quite enjoyed manual nav in the atlantic with SH3 but all the little islands and shallow water parts in the pacific make it a bit too hairy for me in SH4.

Good luck though!

[SteamWake]

I do know that (with the exception of the S class) optimum cruising speed is 10 knots Im not sure what the range. There was a discussion on it wherein someone listed the "expected" range for the different classes.

Try a little searching see if you cant find it.

Also you might try asking in the modding forum. Most likely someone there will have the answer you seek.

There is a very extensive mod in the mod forum of recent day that has vast info on this subject..

[Frederf]

I've found (depite the golden 10kt rule floating around) that 8kts in a Porpoise class sub is significantly longer ranged than 10kts. Around 3x.

[don1reed]

Howdy Mud,

Almost all vessels leaving port ran the "degaussing mile".

First, it degaussed the ship from magnetic influenced weapons. (I don't know off-hand when the procedure began).

Second, it gives the skipper/navigator an idea how many turns his vessel must make in order to maintain x speed. (They could determine how much the marine-growth hindered speed over ground)

The formula was and still is Distance = Speed x Time. Engineering division knows the rate of burn.

It would have been very helpful if the devs would have included a working odometer like the original Silent Hunter. Try to figure
miles per gallon, or miles per ton. Divide total miles by total fuel usage next time out, then apply that to the your future patrol.

Go here : http://en.wikipedia.org/wiki/List_of...ed_States_Navy

to find your class of sub and it's specs.

[Aequitas]

Maybe those numbers would help: they were taken directly from *.sim files from <SH4>\Data\Submarine\<Sub>\*.sim (I've scribed out numbers from files and translated them to understandable form).
[For version 1.3]

Submarine_______|Surfaced_miles_________|knots__________________|Submerged_miles________|knots_______
Balao		|0x466A6000=15000	|0x41200000=10.0	|0x42C00000=96		|0x40000000=2
Gato		|0x466A6000=15000	|0x41200000=10.0	|0x42C00000=96		|0x40000000=2
Porpoise	|0x465F7000=14300	|0x41200000=10.0	|0x42900000=72		|0x40000000=2
S18		|0x45FA0000=8000	|0x41180000=9.5		|0x42C80000=100		|0x40A00000=5
Salmon		|0x466A6000=15000	|0x41200000=10.0	|0x42C00000=96		|0x40000000=2
Sargo		|0x466A6000=15000	|0x41200000=10.0	|0x42C00000=96		|0x40000000=2
Tambor		|0x466A6000=15000	|0x41200000=10.0	|0x42C00000=96		|0x40000000=2

Unfortunately, I can't tell what is the dependence of those "nominal" numbers from named parameters - weather, crew, etc - how much they affect those values.

It seems to me also that all subs of Tambor class and over have too big values of ranges when surfaced - real were around 12000, if I memorize it right.
Also S18 is very surprising after seeing those files - 100 miles at 5 knots submerged... Didn't tested it.