Type IXC range

[Klaus_Doldinger]

Hello all.

Although usually I´m a Type VIIB-C Kaleun, this time I decided to try the US east coast in a Type IXC.

According to Uboat.net and U-Historia.com, Type IXC had a maximum range of 13.450 nm (approx 25.000 Km) at 10 Knots.

Departing from Lorient with the surrounds of Norfolk as patrol area (CA73) I have calculated that travelling between 3-5 knots my maximum range will be only of... more or less 8.100 nm, say more or less 15.000 Km!!:88) So I will must refuel at U-461 in my journey to home or... be lost at sea.

Any explanation, please?

Thanks.

[papa_smurf]

Erm,, normally in a Type IX/C, I can travel to Norfolk and back with fuel to spare at 7kts.

Have you got malfunctions/sabotage on SH3 Commander enabled? (If you have it). As having malfunctions enabled, can affect you fuel efficency.

[Klaus_Doldinger]

Yes, malfunctions enabled, but this is the second time I find the same problem. In my first patrol I reached Port Spain in the Caribbean and I found neccessary to refuel at Corrientes in Las Palmas. It´s true that bad weather makes you sail slower with the same fuel consumption, but sure my UBoot has an abnormally high fuel waste level.

Perhaps SH3 Commander hates me.:stare:

[papa_smurf]

Thing is with malfunctions enabled, are that they are very random - different things can go wrong with you U-boat. i.e - fuel efficency, faulty scopes etc.

Maybe you bad mouthed Herr Doenitz in some way......

[seafarer]

3-5 knots will not give you optimal range. 7-9 knots will maximize your available fuel. I've steamed over 20,000km in a IXC (Lorient to the Seychelles, and back, for example).

[Brag]

3-5 knots will not give you optimal range. 7-9 knots will maximize your available fuel. I've steamed over 20,000km in a IXC (Lorient to the Seychelles, and back, for example).

Yup, 7 knots is what will give you max range (your boat will slow down in rough seas).

[Klaus_Doldinger]

Thanks to all:up:

[Penelope_Grey]

If you don't instal an engine upgrade you see the range on it then! wow!

[U-96]

Keep bernard off of your boat or else you'll end up with a boat with less range then a Canoe.

[Klaus_Doldinger]

Keep bernard off of your boat or else you'll end up with a boat with less range then a Canoe.

:lol:

But... (I´m mechanics incompetent), how it is possible that you get more range at higher speeds, you know, 7-9 knots being a suggested speed instead of 3-5 knots?
(As a seasoned VIIB-C Kaleun travelling not further from Iceland, fuel is not a problem for me)

[Hartmann]

I reached US coast with a IX-B boat and i operated in the zone some days with the fuel at 50% surfacing at night and diving during the day. :yep:

[seafarer]

Keep bernard off of your boat or else you'll end up with a boat with less range then a Canoe.

:lol:

But... (I´m mechanics incompetent), how it is possible that you get more range at higher speeds, you know, 7-9 knots being a suggested speed instead of 3-5 knots?
(As a seasoned VIIB-C Kaleun travelling not further from Iceland, fuel is not a problem for me)


Slower speed may slightly reduce the fuel consumed per unit time, but it will take much longer to cover a given distance, and so you burn more fuel over that time. If the speed is too high, the resistance of the water makes fuel consumption per unit time increase rapidly with increasing speed. You cover the distance in less time, but burn much more fuel per unit time, so total fuel consumption is again high. There is some optimal speed inbetween - see http://www.ussmissouri.com/speedVSFuel.aspx


P.S. and I have no idea how accurate or universal this is, but I always thought that the power needed to drive a ship (roughly) varies as the cube of velocity. So to go from 5 to 8 knots would require about 4.1x the power, but to go from 5 to 17 knots would take more than 39x the power. Or, something like that...what do I know. Damnit Jim, I'm a marine biologist not an engineer.

[Klaus_Doldinger]

Keep bernard off of your boat or else you'll end up with a boat with less range then a Canoe.

:lol:

But... (I´m mechanics incompetent), how it is possible that you get more range at higher speeds, you know, 7-9 knots being a suggested speed instead of 3-5 knots?
(As a seasoned VIIB-C Kaleun travelling not further from Iceland, fuel is not a problem for me)


Slower speed may slightly reduce the fuel consumed per unit time, but it will take much longer to cover a given distance, and so you burn more fuel over that time. If the speed is too high, the resistance of the water makes fuel consumption per unit time increase rapidly with increasing speed. You cover the distance in less time, but burn much more fuel per unit time, so total fuel consumption is again high. There is some optimal speed inbetween - see http://www.ussmissouri.com/speedVSFuel.aspx


P.S. and I have no idea how accurate or universal this is, but I always thought that the power needed to drive a ship (roughly) varies as the cube of velocity. So to go from 5 to 8 knots would require about 4.1x the power, but to go from 5 to 17 knots would take more than 39x the power. Or, something like that...what do I know. Damnit Jim, I'm a marine biologist not an engineer.

For me you´re an engineer. I´m only a ********** lawyer. Thank you!

[Hartmann]

Based in the experience,the best speed is 9 knts for a IX-B boat, perhaps the same for a IX-C