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Old 03-28-06, 04:19 AM   #1
Suicide Charlie
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What are your strategies for conserving fuel while on patrol?

I've found it quite troublesome to conserve a comfortable amount of fuel for maneuvers and a search grid once I reach my patrol grid. The battery reserve is so small that I can't stay submerged for an entired day's worth of travel. I try to use my electric engines as much as possible in order to conserve fuel, but it almost seems pointless because I still end up using a considerable amount of fuel just trying to continue head way while I recharge.
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Old 03-28-06, 04:47 AM   #2
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Always ahead slow while submerged on batteries. Though I did pretty much the same on the surface also. It just took me a lot longer to get anywhere. There were occasions when I wasnt sure if id make it back on the fuel I had.
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Old 03-28-06, 05:10 AM   #3
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I always travel "ahead slow" on diesel (on electric power only if I'm close to the target ir I might become a prey) . So diesel most of the time and slow... unless I spot a target in range and at that moment will be flank speed.

The fuel is enough to patrol the grid, go to other zones better for fishing and return to the port in the same way "ahead slow" (teleporting is not an option)...

I reckon that my commander most of the times give us excellent medals. Because we save tons of diesel for the war effort
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Old 03-28-06, 05:38 AM   #4
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It has already been stated in many posts that the most fuel efficient engine setting is ahead 1/3, and there is little debate in this issue anymore (some people micro manage their engines into a 9knot speed setting).

There is an open debate as to wether running on electrics for as much as you can extends your range even further. I myself think that this actualy shortens your range, but the debate is still open on this last one.
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Old 03-28-06, 12:29 PM   #5
Sailor Steve
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Quote:
Originally Posted by Dantenoc
It has already been stated in many posts that the most fuel efficient engine setting is ahead 1/3, and there is little debate in this issue anymore (some people micro manage their engines into a 9knot speed setting).

There is an open debate as to wether running on electrics for as much as you can extends your range even further. I myself think that this actualy shortens your range, but the debate is still open on this last one.
Fuel effeciency and fuel consumption are not the same. The truth is, the slower you go the less fuel you use. Ahead 1/3 is the best speed for getting anywhere, but once you are at your patrol zone Ahead Slow is best. You won't get anywhere fast, but your time in zone will be doubled. Also, as said, your batteries will also last longer at Ahead Slow.
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Old 03-28-06, 12:55 PM   #6
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Quote:
Originally Posted by Sailor Steve
Quote:
Originally Posted by Dantenoc
It has already been stated in many posts that the most fuel efficient engine setting is ahead 1/3, and there is little debate in this issue anymore (some people micro manage their engines into a 9knot speed setting).

There is an open debate as to wether running on electrics for as much as you can extends your range even further. I myself think that this actualy shortens your range, but the debate is still open on this last one.
Fuel effeciency and fuel consumption are not the same. The truth is, the slower you go the less fuel you use. Ahead 1/3 is the best speed for getting anywhere, but once you are at your patrol zone Ahead Slow is best. You won't get anywhere fast, but your time in zone will be doubled. Also, as said, your batteries will also last longer at Ahead Slow.
You are so correct Sailor Steve.
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Old 03-28-06, 03:04 PM   #7
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Ah, thank you very much. I'm used to having a bit more to work with as I've used a Type IIV more.
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Old 03-28-06, 03:37 PM   #8
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submerge in stormy weather or rough seas. never travel on surface unless its calm....the rougher the seas the more your boat has to fight to compensate.....this is modeled in the game.....there aren't actual current flow models but, there are simulated currents that are randomized and relative to wave height...you will see these effects if you try to manuever your boat manually with rudder instead of using a navigator....its like a random force that is applied to the ship in different directions much like the wind as you travel....when you submerge this effect is minimized ....so its better to run electric until the seas calm down....if you are in a bad season...just write off the fuel or stay idle at sea until you come across better weather....you don't need to worry about food reserves...time is on your side
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Old 03-28-06, 04:45 PM   #9
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Quote:
Originally Posted by Sailor Steve
Fuel effeciency and fuel consumption are not the same. The truth is, the slower you go the less fuel you use. [i]Ahead 1/3 is the best speed for getting anywhere,[i] but once you are at your patrol zone Ahead Slow is best. You won't get anywhere fast, but your time in zone will be doubled. Also, as said, your batteries will also last longer at Ahead Slow.

And here i use "ahead slow", ALL the time. Well, not all the time, i go to flank when trying to gain a firing position if its within a 4 hours of travel.

Question, is one of the factors effecting fuel consumption the RPM's engines are turning? It would stand to reason an ideling (or near ideling) engine at say 1000 rpm uses less fuel then one thats got the throttle stuck open at say 5000 rpm.
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Old 03-28-06, 06:47 PM   #10
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Quote:
Originally Posted by Sailor Steve
Fuel effeciency and fuel consumption are not the same. The truth is, the slower you go the less fuel you use. Ahead 1/3 is the best speed for getting anywhere, but once you are at your patrol zone Ahead Slow is best.
mmmm... I may have misread the question, I though that by "patrol" he meant from the moment he left port until he returned back home, but if by "patrol" he means staying within his assigned grid looking for prey, then my recomendation would be to stay still, all engines stopped, submerged as much as possible, wating like a spider in it's web for the pray to come within range. That way you don't use any fuel at all.
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Old 03-28-06, 07:11 PM   #11
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In the type II ahead 1/3rd while sufaced, ahead slow submerged. Ahead full surfaced to outflank a target (the extra knot on a type II isn't worth the extra consumption imho) and I only submerge before closing the last short distance perpendicular to my target before taking the shot. Or if I have to because of DDs or aircraft.
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Old 03-28-06, 10:20 PM   #12
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Ive completed 5 patrols in my U-14 IIA.

Never had a real problem with fuel. I always run out of eels before fuel becomes critical.

I always transit to my patrol grid square at 10 knots. Once there, I usually steam at 8 knots. Only using flank or full when necessary.

I also check with the Navigator and try various speeds which give the greatest range. My patrols last about 8 days. Although my first lasted 12 days.

I always return to Wilhelmshaven with ~20% fuel.
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Old 03-29-06, 04:08 AM   #13
blackness
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For best Type II fuel v distance performance..

FIRSTLY: Run on surface at 6 knots. You get 40% more distance than Ahead One Third out of your diesel if you do this.

SECONDLY: DON'T think that running submerged on the batteries saves diesel! It actually uses up more in the long run.
How do you think the batteries are recharged? Via the diesel engines!

You can check this; ask the navigator for the max distance at current speed while you're recharging the batteries. His answer will be a shorter distance than you might expect!

The explanation: recharging the batteries is an additional energy conversion which makes for a less efficient diesel to distance performance.. Diesel -> Electricity -> Moving The Sub is less efficient than Diesel -> Moving The Sub.
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Old 03-29-06, 04:38 AM   #14
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Quote:
Originally Posted by blackness
The explanation: recharging the batteries is an additional energy conversion which makes for a less efficient diesel to distance performance.. Diesel -> Electricity -> Moving The Sub is less efficient than Diesel -> Moving The Sub.
Yes, of course, the laws of thermodynamics.... Even if that wasn't enough, there's still the fact that while submerged ALL of the sub suffers resistance to movement by water, whereas while surfaced only the lower half of the sub suffers resistance from water (the top suffers wind resistance, but this is nothing compared to water). Being how (for the game) surfaced means diesel and submerged means electrics, then you have yet another argument for NOT using the electrics ever.... the thing is that it isn't at all clear if this is modeled in the game or not (It HAS been known to overlook very important details). You can't really trust the navigator's predictions 100% neither, since several people have caught him making idiotic predictions

To put this matter to rest one would need to actualy test it out, by traveling with both methods, following exactly the same course, with exactly the same weather/sea conditions, with exactly the same crew maning the engines in both ocations, and then comparing results.... but I'm to lazy to do this

Besides, to me it's like a matter of principle, to play realisticaly and use the diesels as much as I can, game behaviour not withstanding
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Old 03-29-06, 03:44 PM   #15
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I'm not sure I agree about the surface-versus-submerged resistance. Yes, surfaced there is less area interacting with the water, but the problems of surface tension and wave resistance are immense, especially surfaced wave resistance. The hull creates waves of it's own as it moves through the water, and these waves become hills the boat literally has to climb, which costs both speed and fuel.

I almost always cruise at 1/3 speed, unless it's critical in which case I make my way home at Ahead Slow. Blackness, I'll try running at six knots and see what happens.

mike_espo: U-14's getting a little crowded with two captains...or is it three now?
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