Good at math? I have a problem for you.

Ducimus · 01-06-07, 04:07 PM

It's all about FUEL! Im sure this will draw Letum like a magnent

One of the biggist mysteries to me, is exactly how much fuel is in a uboat, and.. the rate of consumption. But to boil the fat away, ive always wondered exactly how much fuel a trip to X destination would consume.

Awhile ago, i made this observation. Its a bit from Donitz's war diary:
(Picture linked cause it skews the page)
http://www.ducimus.net/sh3/BDU_on_Fuel.JPG

From this i make 4 assumptions:
1.) He's talking about Nautical Miles

2.) CBM means, Cubic Meters

3.) Hes noting how much fuel a uboat will have after making the trip To that area. Not how much they have to operate in that area, with the to and from trip already accounted for. (or do i have this backwards?)

4.) These are ballpark figures, not exact ones. We have no idea under what conditions or assumptions (if any) he made these calculations.

Now, according to this page:

http://www.uboataces.com/uboat-type-ix.shtml
A....
IXB has 165 Tons of fuel
IXC has 208 tons of fuel
IXC/40 has 214 tons of fuel.

So my thought is, to take BDU's estimate of how much fuel is remaining in the tanks after making a trip to X locaton, convert it to metric tons, and then convert that to a percentage against its total capcity?

What im having trouble with, is the density of the fuel, and finding an applicable formula to apply it too. And, i have to admit, mathimatics was never my most keen subject.

azn_132 · 01-06-07, 04:10 PM

Quote:

Originally Posted by Ducimus

It's all about FUEL! Im sure this will draw Letum like a magnent

One of the biggist mysteries to me, is exactly how much fuel is in a uboat, and.. the rate of consumption. But to boil the fat away, ive always wondered exactly how much fuel a trip to X destination would consume.

Awhile ago, i made this observation. Its a bit from Donitz's war diary:
(Picture linked cause it skews the page)
http://www.ducimus.net/sh3/BDU_on_Fuel.JPG

From this i make 4 assumptions:
1.) He's talking about Nautical Miles

2.) CBM means, Cubic Meters

3.) Hes noting how much fuel a uboat will have after making the trip To that area. Not how much they have to operate in that area, with the to and from trip already accounted for. (or do i have this backwards?)

4.) These are ballpark figures, not exact ones. We have no idea under what conditions or assumptions (if any) he made these calculations.

Now, according to this page:

http://www.uboataces.com/uboat-type-ix.shtml
A....
IXB has 165 Tons of fuel
IXC has 208 tons of fuel
IXC/40 has 214 tons of fuel.

So my thought is, to take BDU's estimate of how much fuel is remaining in the tanks after making a trip to X locaton, convert it to metric tons, and then convert that to a percentage against its total capcity?

What im having trouble with, is the density of the fuel, and finding an applicable formula to apply it too. And, i have to admit, mathimatics was never my most keen subject.

What? I dont get what this is all about.

Ducimus · 01-06-07, 04:14 PM

Quote:

Originally Posted by azn_132

What? I dont get what this is all about.

In a nutshell.

60 CBM is how many ton's?

X number of tons converted from the CBM is how much of the total fuel capcity as a percentage?

edit: and to me the question still remains, is BDU talking about how much fuel is in the tanks after making the trip, or how much fuel the boat has to operate in that area, not counting the fuel used going to and from that area. I think that answer lays in how large or small a percentage the "CBM" is against a boats total fuel capcity

hyperion2206 · 01-06-07, 04:20 PM

I searched the internet and found that for example 140 CBM equals 140000 liters or 36984.087330141 US liquid gallons. Hope that helps.

nightdagger · 01-06-07, 04:21 PM

Density = Mass / Volume.

Find the density and either the mass (tons) or volume (cubic meters) and you can convert.

bigboywooly · 01-06-07, 04:31 PM

From the way it reads
The Uboats will have that much fuel left to operate IN the region

In other words journey to and from removed from equation and thats whats left
Of course it has to be guess work figures as weather/engine condition and usage and evasive tactics employed on either route would all impact on fuel reserves

And I dont think they had at that time actually ran a boat to those locations
And of course you dont know whether that includes refuelling

hyperion2206 · 01-06-07, 04:51 PM

If you look at this page Sydney seems to be the nearest location, therefore they U-Boats must be stationed in Penang, right? But why does a IXC only have 140 cbm of fuel left (I mean it's only 2200 miles). So I guess 140cbm is the amount of fuel that can be "wasted" in the operation area, when 140cbm are used it has to return.:hmm: But that's just crappy guesswork.

Ducimus · 01-06-07, 06:27 PM

Quote:

Originally Posted by hyperion2206

If you look at this page Sydney seems to be the nearest location, therefore they U-Boats must be stationed in Penang, right?

He meant the OTHER sydney

http://en.wikipedia.org/wiki/Sydney,_Nova_Scotia

01-07-07, 02:37 AM

Perhaps you can use this pdf. Its a description of how to convert to the XXI made by von Topp to help other commanders.

It talks about fuel and usage of it.

http://files.filefront.com/berlegung.../fileinfo.html

hyperion2206 · 01-07-07, 05:20 AM

Quote:

Originally Posted by Ducimus

Quote:

Originally Posted by hyperion2206

If you look at this page Sydney seems to be the nearest location, therefore they U-Boats must be stationed in Penang, right?

He meant the OTHER sydney

http://en.wikipedia.org/wiki/Sydney,_Nova_Scotia

There are 2 Sydneys?

I forgot that the english speaking people are not very creative when it comes to naming their cities:p:rotfl: (No offense ment

)

Sailor Steve · 01-07-07, 03:52 PM

Nothing of the kind. Colonists liked to name cities after ones in the Old Country to remind them of home. There are two major Portlands in the U.S., plus a bunch of other cities and towns named for former home cities in a variety of countries.

TarJak · 01-08-07, 01:31 AM

Both Sydney's were named after the then(1788) English Home Secretary, Thomas Townshend, Lord Sydney. This was a common practise as explorers used the names of people who commissioned their journeys or whom they had a chance of gaining favour from.

There are also Sydney's in North Dakota, South Africa, Vanuatu, and Florida.

fabel · 01-08-07, 02:48 AM

Quote:

What im having trouble with, is the density of the fuel, and finding an applicable formula to apply it too. And, i have to admit, mathimatics was never my most keen subject.

I always let my navigator calculate the maximum range at current speed. It's interesting though, one time I got the message 'We're out of diesel fuel, Sir!', but the engines still could ran an additional 200 km. So I think you also got a reserve or something?

Dietrich · 01-08-07, 08:11 AM

[quote=fabel]

Quote:

It's interesting though, one time I got the message 'We're out of diesel fuel, Sir!', but the engines still could ran an additional 200 km. So I think you also got a reserve or something?

If you're really desperate, go to periscope and get another 50+km out of your batteries.

01-06-07, 04:07 PM	#1
Ducimus Rear Admiral Join Date: May 2005 Posts: 12,987 Downloads: 67 Uploads: 2	Good at math? I have a problem for you. It's all about FUEL! Im sure this will draw Letum like a magnent One of the biggist mysteries to me, is exactly how much fuel is in a uboat, and.. the rate of consumption. But to boil the fat away, ive always wondered exactly how much fuel a trip to X destination would consume. Awhile ago, i made this observation. Its a bit from Donitz's war diary: (Picture linked cause it skews the page) http://www.ducimus.net/sh3/BDU_on_Fuel.JPG From this i make 4 assumptions: 1.) He's talking about Nautical Miles 2.) CBM means, Cubic Meters 3.) Hes noting how much fuel a uboat will have after making the trip To that area. Not how much they have to operate in that area, with the to and from trip already accounted for. (or do i have this backwards?) 4.) These are ballpark figures, not exact ones. We have no idea under what conditions or assumptions (if any) he made these calculations. Now, according to this page: http://www.uboataces.com/uboat-type-ix.shtml A.... IXB has 165 Tons of fuel IXC has 208 tons of fuel IXC/40 has 214 tons of fuel. So my thought is, to take BDU's estimate of how much fuel is remaining in the tanks after making a trip to X locaton, convert it to metric tons, and then convert that to a percentage against its total capcity? What im having trouble with, is the density of the fuel, and finding an applicable formula to apply it too. And, i have to admit, mathimatics was never my most keen subject.

01-06-07, 04:20 PM	#4
hyperion2206 Ace of the Deep Join Date: Jul 2006 Location: Cologne, Germany Posts: 1,227 Downloads: 8 Uploads: 0	I searched the internet and found that for example 140 CBM equals 140000 liters or 36984.087330141 US liquid gallons. Hope that helps. __________________ Career of Captain Jack Shaftoe:

01-06-07, 04:21 PM	#5
nightdagger Officer Join Date: Nov 2006 Location: Houston, TX Posts: 243 Downloads: 0 Uploads: 0	Density = Mass / Volume. Find the density and either the mass (tons) or volume (cubic meters) and you can convert. __________________

01-06-07, 04:31 PM	#6
bigboywooly Rear Admiral Join Date: Apr 2006 Location: Swindon, England Posts: 10,151 Downloads: 35 Uploads: 0	From the way it reads The Uboats will have that much fuel left to operate IN the region In other words journey to and from removed from equation and thats whats left Of course it has to be guess work figures as weather/engine condition and usage and evasive tactics employed on either route would all impact on fuel reserves And I dont think they had at that time actually ran a boat to those locations And of course you dont know whether that includes refuelling __________________ My mediafire page http://www.mediafire.com/?11eoq19bq9r41

01-06-07, 04:51 PM	#7
hyperion2206 Ace of the Deep Join Date: Jul 2006 Location: Cologne, Germany Posts: 1,227 Downloads: 8 Uploads: 0	If you look at this page Sydney seems to be the nearest location, therefore they U-Boats must be stationed in Penang, right? But why does a IXC only have 140 cbm of fuel left (I mean it's only 2200 miles). So I guess 140cbm is the amount of fuel that can be "wasted" in the operation area, when 140cbm are used it has to return.:hmm: But that's just crappy guesswork. __________________ Career of Captain Jack Shaftoe:

01-07-07, 02:37 AM	#9
Mav87th Stowaway Posts: n/a Downloads: Uploads:	Perhaps you can use this pdf. Its a description of how to convert to the XXI made by von Topp to help other commanders. It talks about fuel and usage of it. http://files.filefront.com/berlegung.../fileinfo.html

01-07-07, 03:52 PM	#11
Sailor Steve Eternal Patrol Join Date: Nov 2002 Location: High in the mountains of Utah Posts: 50,369 Downloads: 745 Uploads: 249	Nothing of the kind. Colonists liked to name cities after ones in the Old Country to remind them of home. There are two major Portlands in the U.S., plus a bunch of other cities and towns named for former home cities in a variety of countries. __________________ “Never do anything you can't take back.” —Rocky Russo

01-08-07, 01:31 AM	#12
TarJak Fleet Admiral Join Date: Jul 2006 Location: Sydney, Australia Posts: 17,052 Downloads: 150 Uploads: 8	Both Sydney's were named after the then(1788) English Home Secretary, Thomas Townshend, Lord Sydney. This was a common practise as explorers used the names of people who commissioned their journeys or whom they had a chance of gaining favour from. There are also Sydney's in North Dakota, South Africa, Vanuatu, and Florida.