prototype DIY 3-bearing AOB Sliderule released

[Pisces]

I have created a circular version of the tool I mention in this post some time ago. It isn't completely to my taste yet. The AOB should be given with reference to the last bearing taken for ease of use. And hopefully I can add functionality to allow unequal time intervals. However I have decided to upload this prototype now since I have to live up to the promise somehow someday. It was triggered by a topic in the Sh4 forum. And maybe I can get a bit of feedback before I develop it further.



Filefront description:
Sliderule to compute Angle On Bow (when stationary, if moving Direction of Relative Movement wrt the first bearing) based on 3 bearings only, in 2 equal time intervals. Intended for use with Silenthunter 3 or 4. Inspired by a straight design ("Another Course Computer") on this site: https://www.gizmology.net/silenthunter/ [EDIT]Unfortunately his link to the 'ACC' is dead, possibly even infected by a trojan. See the first link in this post for a (bad) webcam image of the one I build.

DIY- circular sliderule PDF:

https://ricojansen.nl/downloads/3BearingAOBfinder.pdf

1. Print out
2. Cut out
3. Don't forget the window on front disk
4. Laminate both disks
5. Make a hinge in the center.
6. Instructions for use are on the front disk.

7. Be patient! It takes time for a good meaningfull AOB value. Forget the 3m(15s)-rule for this thing. Allowing longer time periods for more bearing drift leads to more accurate values of AOB.

A complete walkthrough is something I keep promising , but I do not have time to make right now. But I wil do it before I go on my next patrol. (got to force myself with something, don't I. ) Anyway, I think the front disk speaks for itself. If not, ask!

[gasparweb]

Very Usefull! Seems very interesting to learn!
But, please: Copy and Paste the filefront link again (not shoted)

Thanks in advance sir!

[Pisces]

Thanks, it should work now.

[jmr]

If it weren't for your post in OLC's Gold MKII thread I would have never known about your wiz wheel. Looks like I'll be making a trip to Kinko's to do some laminating today. This will be my 5th whiz wheel I've made so far

A walkthrough wouldn't hurt if you're up for it

[Pisces]

Yes, it didn't receive much attention. Actually, it's been downloaded a 100 times sofar. The steps are explained on the front side. There is not much you can do wrong. But I supose it need some kind of walkthrough.

Unfortuneatly I don't have the time for it. Now less than before, as I'm starting IT courses tomorrow that has top priority. And my Sh3 game is busted at the moment. Need to reinstall it first.

I did write some posts here and there whenever someone mentioned he wanted to close up on a hydrophone only contact, and didn't have a clue how to. And often in relation to Mittelwaechter hydrophone technique. This tool is a shortcut for the initial drawings he does.

http://www.subsim.com/radioroom/showthread.php?t=110619

[Sea Hawk]

Ive used it quite a few times. I find it realy usefull and Ive not yet got round to laminating it and hingeing it. More difficult to use sliding about pieces of paper, but I do get there in the end.

I particularly like the method of moving the U-boat after the 3rd bearing and taking a 4th bearing to get the exact position of the target as well as its AOB.

Many thanks Pisces, its much appreciated.