Damn we're out of fuel

[DavyJonesFootlocker]

Dude, just regulate your boat's speed for fuel efficiency. Go 2/3 speed and don't sail for Buenos Aires next time.

[Kirby_TFS]

I know that going full or flank is a fuel eater, but is going 1/3 also bad? I guess my real question is what is the best surface speed. I make alot of patrols going and returning at 1/3 and I do have fuel problems. Maybe I'm going too slow! Also when you are at all stop we still hear the diesel running. I assume that it is also using fuel when at all stop?

[DavyJonesFootlocker]

That's the sound of deceleration. 1/3 speed is too slow for me. I use 2/3 and only use 25% fuel on a month-long patrol. You can save fuel whenever an air threat is nearby by submerging and switching off for about an hour then surface.

[Torps]

Originally Posted by Kirby_TFS

I know that going full or flank is a fuel eater, but is going 1/3 also bad? I guess my real question is what is the best surface speed. I make alot of patrols going and returning at 1/3 and I do have fuel problems. Maybe I'm going too slow! Also when you are at all stop we still hear the diesel running. I assume that it is also using fuel when at all stop?

Back in HS a long time ago, I interviewed a WWII Submariner. He said
you get the best range in a Gato class sub by traveling between 11.25 knots and 8.0 knots. He mentioned your range depends on the water currents direction and wave height, wind speed and sub displacement. They had figured out how to manipulate/calculate and be able to extend there range by an additional 1500 knotical miles if they had to. Dont ask me about the formula I have no idea. Overall the best speed during calm weather was 9.8 knots to 10.2 depending on the subs displacement at the time.

[seafarer]

Originally Posted by Kirby_TFS

I know that going full or flank is a fuel eater, but is going 1/3 also bad? I guess my real question is what is the best surface speed. I make alot of patrols going and returning at 1/3 and I do have fuel problems. Maybe I'm going too slow! Also when you are at all stop we still hear the diesel running. I assume that it is also using fuel when at all stop?

Depends on what you want to accomplish - covering the maximum distance possible, or maximizing the time at sea. Going very slow will allow you to run the engines longer, so stay at sea much longer. But, you'll be going so slow that you will cover less distance overall. Going at around 9 knots means you will achieve the maximum distance cruised possible, but may need to make a port call sooner then if you went slow.

Look at the fuel stats for the USS Missouri's fuel figures to see what I mean:
http://www.ussmissouri.com/speedVSFuel.aspx

[Snuffy]

Its a long walk home capt'n

[Kirby_TFS]

I tried running at 2/3 or about 8-9 knts last night in a Tambor class boat and I only used about half the fuel it normally takes when running at 1/3. I also tried to limit my submerged times so I wouldn't have to recharge as much. I also turned off the auto-recharge when the batteries got to 100%. By running at 2/3 I now have some fuel to actually chase some targets instead of getting to the patrol area and sitting waiting and praying a ship comes reasonably close so I wouldn't have to chase it far. Thanks for all the help.

[DavyJonesFootlocker]

Good for ya Kirby! Happy sailing.