Bearing Rate Computer slide rule
 

If you are interested in one, I put the graphics for it in these two threads:

http://www.subsim.com/radioroom/showthread.php?t=140397

http://www.subsim.com/radioroom/showthread.php?t=140421

You print them out, then cut them out and pin them together, and you'll probably want something to use as a cursor.

If you aren't familiar with the techniques of making "wheels", see these threads:

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

http://www.subsim.com/radioroom/showthread.php?t=114351

Saweeeeeeet! When I was reading up on plotting and TMA in chapter 10 of the NRTC Operational Specialists manual I kept thinking how nice it would be to have that bearing rate computer added to my homemade whiz wheel collection :}

Thanks for this, Bill!

I have a feeling it'll take a while to figure out. Once I do, however, I'll try it out. Wonder what this will do for my TMA solutions.

My pleasure.

I probably should have posted it earlier, but I don't play DW (just SHIII) so for me it was just a "Hey, I'll make one and see what it can do" kind of thing. So I went through a couple of TMA exercises with it, then shoved it in a drawer with the other wheels I don't use. I only use Hitman's Kriegsmarine whiz-wheel at this point, because it's the only one relevent to my needs. I think I made it about a year or so ago.

All I did to make it was to grab the graphic from the manual and instructions on how to do a TMA, make two copies of it, and erased the parts that weren't relevent to that particular part of the wheel. I'm no graphics wizard, but it is usable. Someone else with more talent should make a nicer one.

I actually have a real one, but I admit I don't use it.

It's been brought to my attention that there should be *4* wheels, not just two.

You can still use them, you just have to print each sheet twice and trim one of each appropriately.

IIRC in DW you can get the Bearing Rate on the Nav Map. I'm not sure if its based on your TMA Plot's solution or on actual sonar data.




One of these days I got to print out that Is-Was so i can use it on the Kilo for determining target course. :hmm:

I wonder if you can buy this top seacret tech hmmm.

I think it's completely based on yuour TMA solution. I never saw the rate value until I entered a solution. (But I haven't used it much either.) So if that solution doesn't resemble the (short-term) bearing fan in the least of ways it's meaningless.

Possibly. You might be able to find one on Ebay or something, but to be quite frank you will most likely end spending more than you would spend on the materials to make them.

Here is how I build my wheels:

First, I obviously print out the appropriate graphics. I generally use inkjet cardstock. I almost always have some because I use it to print out my QSL cards (I'm a ham radio operator).

I'll do a rough cut-out of the individual wheels, leaving plenty of excess at the edges.

Then, if I want it to be a very durable and stiff wheel, I take an Elmers glue stick (don't use wet Elmers!) and completely cover the back of each wheel, then stick another piece of cardstock to it. Then I put the result between two heavy books. If you aren't making a "permanent" wheel, you can skip this step. I will say though that I still use wheels I made before I started doing that step, and they are in perfect shape after a couple of years, so this may be "overkill". At any rate, feel free to skip this step.

Then, I use self-stick lamination to laminate BOTH SIDES of each wheel. Some people thermally laminate them. Whatever trips your trigger.

After that, really all you have to do is cut them out carefully along the edges, and pin them together. I used to use two push-pins. I'd use pliers to take the pin out of one of the heads, then I'd use the other pin to make the holes in the wheels. After putting it all together, I would use wire cutters to trim the pin, and I'd use the head of the other pin, along with a dab of super glue, to hold it all together. These days, I still use a pin to make the whole, but I use small hardware (nuts and bolts) to hold them together.

The only critical part of making them is putting the hold in the center of each wheel. Even then, if you are off by a *LITTLE* it won't effect the accuracy enough that you would notice in practice.

Go ahead and make one. You'll get hooked. :yep:

Theres only 2 wheels on a "widger" and a cursor. :know:

I used to have a list of 101 things you could use it for, but its long since misplaced :oops:

And like Bill probably knows, by the time you get to know how to use these things properly, 95% of the time you can do it quicker in your head :up: :up:

Well, yes, and no.

Certainly it's true that practicing and using wheels on a regular basis, or indeed any manual procedure gives you a good fundamental understanding of the problem, and can also help you develop a sixth sense about where you are in relation to your target, and vice versa.

On the other hand, I still use the wheels on a regular basis. There are some things I find them indispensible for, like calculating target speed. Funny side story: I was watching the sculling qualifications for the Olympics a while back, and it struck me: They travel 2000 meters in a certain amount of time, I wonder how fast that is in knots? Whipped out my trusty Kriegsmarine whiz-wheel (because unlike the BRC or the SACF/IS-WAS, it's measurement is meters, not yards), and figured it out. It was something on the order of 9+ knots, by the way.

I imagine that if you wanted to do a manual TMA, this would be a must-have. I'm going to build another one myself in the near future and try it out in SHIII.

Now, I could write the software to do all this crap for me: I'm a programmer by trade. But I have to admit, there is just something retro-cool :cool: about whipping out a slide rule to calculate something. It's cool enough that I don't bother reaching for my TI-82 programmable anymore, or any other. If I have something that needs figuring, I whip out my trusty Pickett N-200ES Pocket trig.

Broken URLs?
 

My friend, the urls you posted are no longer visible (if my PC has not gone crazy). But if you own a Bearing Rate Computer, I would really appreciate if you scan it with fair quality an post it again, or recommend a url that I can visit and dload a printable version to make one at home.....Thanks in advance....

Check this recent thread (ekelund range calculator):

http://www.subsim.com/radioroom/showthread.php?t=154396

Well, *PART* of them work, for the inner two wheels.

Here they are again:

Outer two wheels:

http://img441.imageshack.us/img441/2403/brcouter.jpg

Inner two wheels:

http://img441.imageshack.us/img441/1897/brcinner.jpg

You print each page out twice, and cut away the outer rings on one of each print out, so you have 4 'wheels' all of different sizes that should nest upon each other.