Best Fuel economy?

[liluoke]

How do you achieve best fuel economy with the sub?

Standard propulsion + what speed? Ahead standard? Ahead flank apparently burns more fuel (just like driving your car too fast.. haha)

Anything else that may conserve fuel for a trip back to port?

Sorry if this is a repost.

[teg916]

The slower you go the less you burn. Try experimenting by setting a speed and asking your navigator for max range at current speed.

[derrinurban]

I just follow the slower is more efficient philosophy. I am sure someone here has some hard numbers. When heading back to port (all torpedo's spent), I normally plot the course, then ask the NO for distance to end of plotted course and maximum distance at current speed. then adjust my speed to get me there the quickest while not running out of fuel.

I did actually have one mission where I was running so low on fuel that I had to run submerged at ahead slow (best use of batteries) till the batteries were drained, surface and run at ahead slow (order the CE not to recharge the batteries) and barely made it.

DU

[FIREWALL]

Weather is an issue too.

[Fishers of Men]

I will set diesel engines to 7 knots, in my type VII boat, for maximum range. But in rough seas, you will need to use more fuel to keep moving ahead at that pace. I will set the telegraph to 8 knots to achieve a 6-7 knot speed. On a smooth ocean, you can save quite a lot of fuel and extend your range.

FoM

[gordonmull]

There is an optimal speed for each u-boat type but I can't remember what they are. Going too slow seems ineffiecient as well as going too fast. Think there's a mod somewhere that sets ahead one-third as your optimal speed for fuel economy for each boat. Anyway, I just use one-third because as far as I can remember its as near as verdamt.

[sharkbit]

Originally Posted by derrinurban

I just follow the slower is more efficient philosophy.

That is not necessarily true. On average, depending on sub type, 7-8 knots is most efficient. The range falls off if you go slower or faster than that.

What I usually do when I get a new type of sub, if the weather is good, I'll check the range settings at each engine telegraph position(along with speeds) and also at various knot settings to find that sweet spot. I have them recorded on a spread sheet for future reference.

[irish1958]

This was a concern in developing GWX. The ranges of the U-boats were tuned to be (on the average) the normal ranges for each boat at ahead standard. Sea state has a major effect on fuel economy. (and in real life, so does wind, ocean streams and circulation, quality of oil, state of the engine, etc.)
Using the battery doesn't help, as recharging requires one engine to run to supply the energy to run the generator. I am not sure of this, but I suspect it would worsen markedly your range as pushing an U-boat against the resistance of sea water as opposed to air should increase the forces necessary to move the boat.

I just follow the uboat commanders handbook which states, the default patrol speed is Slow. Those other speeds are just for certain situations that may arise. It works. The most important thing you can do to keep your range high is NOT upgrade your diesels. The upgrade makes for unrealistic speeds anyway. Try it any way you like. My IXB always makes it back from Capetown, without refueling. Unless I sunk. Don't like those Capetown patrols. IXCs and IXD2s are better suited to that area. Long long ride.

[Commander Gizmo]

Originally Posted by irish1958

This was a concern in developing GWX. The ranges of the U-boats were tuned to be (on the average) the normal ranges for each boat at ahead standard. Sea state has a major effect on fuel economy. (and in real life, so does wind, ocean streams and circulation, quality of oil, state of the engine, etc.)
Using the battery doesn't help, as recharging requires one engine to run to supply the energy to run the generator. I am not sure of this, but I suspect it would worsen markedly your range as pushing an U-boat against the resistance of sea water as opposed to air should increase the forces necessary to move the boat.

I had tested this in GWX2.1 and can definitely say that what you say makes perfect since for real life physics, but isn't modeled in the game. I could not get the range needed to make it back to port no matter the speed setting once and made it there with a quarter tank by running very slowly submerged till 25% battery and then recharging on the surface while running slow. Can't recall the weather at the time, but it was consistent the whole trip home. I remember because I was watching it closely for changes.

I think the main reason for this is that the batteries do not seem to recharge at much of a different rate when the engines are at flank or at slow. Checking the RPM gauges revealed the charging engine to always run at a particular speed I believe, though I can't recall for sure.

[Sailor Steve]

It has long been noted that submerging and recharging is the most effecient method of travel in SH3. Not so in real life, and it was fixed for SH4, but in SH3 it works, cheating though it certainly is.

I always use Ahead 2/3 in GWX, and it feels pretty right to me. Ahead slow will use less fuel, and is great while patrolling, but while transitting to and from the patrol grid it takes forever to get anywhere.

[liluoke]

i see, good points!

i think going TOO slow will also be a waste of fuel, there has to be an optimum speed somewhere in between, i'll figure it out with the range button and let you guys know...

lol i remember in das boot bad weather makes you burn a lot of fuel, should I go to periscope depth and try to ride out the storm like in the movie? =p

[gordonmull]

Save yourself the hassle! Here is a thread which should have what you're looking for.

http://www.subsim.com/radioroom/show...ght=speed+fuel

[Brer Rabbit]

I make frequent use of the resupply ships, ie greenland, Portgual and spain, and plan my routes and patrols accordingly.

Happy Hunting

[Pohl]

aim for 8 knots, in a Type IXD2 I get a fuel economy of 106,XXX km, on the Type XXI I get 55,XXX km