Bearing Rate Computer

Puster Bill · 08-06-08, 08:00 PM

I know it's post WWII, but I suppose you could cheat

Cut out the two wheels, and pin them together along with something for a cursor. Google "Bearing Rate Computer" to find instructions on how to use it.

Rockin Robbins · 08-06-08, 08:11 PM

Pretty awesome! Do you know what year that circular slide rule of yours came from? Do we know for sure that nothing like that was used during the war? I know they did bearing rate plots and derived enemy relative course and speed. They must have had a similar tool but I bet it was a straight slide rule (a slip-stick), not a circular one.

This is important because bearing rate charts were extensively used by the real submarines and we don't use them at all.

Puster Bill · 08-06-08, 09:28 PM

For targeting problems, they used the Submarine Attack Course Finder/IS-WAS. It was also a circular slide rule, and this thread has all you need to make and use one:

http://www.subsim.com/radioroom/showthread.php?t=106923

Pisces · 08-07-08, 06:53 AM

Are you sure they are only 2 disks, and not supposed to be 4 free rotating scales?

Puster Bill · 08-07-08, 09:01 AM

You know what, I think you may be right. Here is an actual photograph of one:

So really the only difference is that you print each page twice, and cut them out appropriately.

Good catch. I never really used it much, I just made one and fiddled with it a bit.

Pisces · 08-07-08, 05:08 PM

Yeah, I noticed the 90 degree mark (sine scale) was against about 4050 yards (pretty much 2nm) so I started wondering if that relation was important. But then I thought "closest point of approach" calculations or matching AOB vs range would allways come out the same. That can't be good. It's probably in that state because of the last user's calculation, before photocopying.

Puster Bill · 08-09-08, 07:28 PM

Quote:

Originally Posted by Pisces

Yeah, I noticed the 90 degree mark (sine scale) was against about 4050 yards (pretty much 2nm) so I started wondering if that relation was important. But then I thought "closest point of approach" calculations or matching AOB vs range would allways come out the same. That can't be good. It's probably in that state because of the last user's calculation, before photocopying.

I grabbed it from a PDF of a manual on how to do TMA's and use the Manuevering Board. It wasn't clear how many wheels there were.

Seminole · 08-09-08, 07:38 PM

Quote:

but I suppose you could cheat

Ohhhh...ohhhh...ohhhh..what he said...I feel so dirty...must go take a shower....man if I get killed in game ..I'm such a fanatical ded is ded player...I have to wait 25 years in real time before playing again in order to simulate growing up and being re-educated in sub warfare....

(Yeah..right

)

Thanks for the calculator...

08-06-08, 08:00 PM	#1
Puster Bill Grey Wolf Join Date: May 2006 Location: BA8758, or FN33eh for my fellow hams. Posts: 833 Downloads: 0 Uploads: 0	Bearing Rate Computer I know it's post WWII, but I suppose you could cheat Cut out the two wheels, and pin them together along with something for a cursor. Google "Bearing Rate Computer" to find instructions on how to use it. __________________ The U-Boat Commander of Love

08-06-08, 08:11 PM	#2
Rockin Robbins Navy Seal Join Date: Mar 2007 Location: DeLand, FL Posts: 8,900 Downloads: 135 Uploads: 52	Pretty awesome! Do you know what year that circular slide rule of yours came from? Do we know for sure that nothing like that was used during the war? I know they did bearing rate plots and derived enemy relative course and speed. They must have had a similar tool but I bet it was a straight slide rule (a slip-stick), not a circular one. This is important because bearing rate charts were extensively used by the real submarines and we don't use them at all. __________________ Sub Skipper's Bag of Tricks, Slightly Subnuclear Mk 14 & Cutie, Slightly Subnuclear Deck Gun, EZPlot 2.0, TMOPlot, TMOKeys, SH4CMS

08-06-08, 09:28 PM	#3
Puster Bill Grey Wolf Join Date: May 2006 Location: BA8758, or FN33eh for my fellow hams. Posts: 833 Downloads: 0 Uploads: 0	For targeting problems, they used the Submarine Attack Course Finder/IS-WAS. It was also a circular slide rule, and this thread has all you need to make and use one: http://www.subsim.com/radioroom/showthread.php?t=106923 __________________ The U-Boat Commander of Love

08-07-08, 09:01 AM	#5
Puster Bill Grey Wolf Join Date: May 2006 Location: BA8758, or FN33eh for my fellow hams. Posts: 833 Downloads: 0 Uploads: 0	You know what, I think you may be right. Here is an actual photograph of one: So really the only difference is that you print each page twice, and cut them out appropriately. Good catch. I never really used it much, I just made one and fiddled with it a bit. __________________ The U-Boat Commander of Love

08-07-08, 06:53 AM	#4
Pisces Silent Hunter Join Date: Dec 2004 Location: AN9771 Posts: 4,904 Downloads: 304 Uploads: 0	Are you sure they are only 2 disks, and not supposed to be 4 free rotating scales?

08-07-08, 05:08 PM	#6
Pisces Silent Hunter Join Date: Dec 2004 Location: AN9771 Posts: 4,904 Downloads: 304 Uploads: 0	Yeah, I noticed the 90 degree mark (sine scale) was against about 4050 yards (pretty much 2nm) so I started wondering if that relation was important. But then I thought "closest point of approach" calculations or matching AOB vs range would allways come out the same. That can't be good. It's probably in that state because of the last user's calculation, before photocopying.