Fuel or Speed

[NZsnowman]

I have always wondered what U-Boat Caption did during the war on the way back to base after a patrol.

a) Travel back to base as fast as they could, base on there able fuel to minmum the turn-a-round between patrols.

or...

b) Travel back at slower speeeds to safe fuel for the war.

Which was more important, saving fuel or a quicker turn-a-round?

[Letum]

Usually fuel.
You would almost always go at the most fuel efficient speed (~7knts) if you are not chasing something or running away from something. This is still the case, even if you have 80% fuel, but no torps. You Still go home at cruising speed.
A) Fuel is expensive.
B) The motors will have a longer life.

Exceptions where made in dangerous waters (Biscay post '42).

[bigboywooly]

Yep fuel efficiency is the most important
Most boats returned home with no fuel but plenty of torpedos
Quite the opposite of SH3

[_Seth_]

I read somewhere that 9 kts was the most fuel efficient speed..Is it? Does this vary depending on the boat you have + equipment?

[Jimbuna]

Good question Seth :yep:
Despite the number of times this topic has come up I'm not sure anyone has come up with a definitive answer :hmm:

[Sailor Steve]

I always set for two-thirds, which is around 9 knots in a VII and 7 knots in a II. I could be wrong but I'm a trusting innocent soul and I'm also lazy.

[Letum]

7knts is the only value I can find with historical references.

In SHIII on a VIIC with no engine modifications the ideal speed in perfect weather is about 7.5 - 8 knts.

I have not studied how this changes with different boats / engines / weather.

[Respenus]

I'd say fuel. You can't get home without it. So unless you have a big jussy target/convoy to blow to kingdom come, you stay put at the optimal speed!

[fredbass]

Though it varies some, when surfaced and you're batteries are back up to 100%, you can have the Navigator check your maximum range at current speed and you'll get a fairly good idea of what you're working with.