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View Full Version : Any math-heads used a real manoeuvring board to plot solutions?


Elphaba
04-10-19, 10:55 PM
I found a great video on YouTube instructing people taking their Nav Seaman exams.

https://www.youtube.com/watch?v=9Qov01O1mg8&t=621s

And it got me thinking, using a mouse for plotting has never been fun; even with all the extremely well made mods in SH3-5.

As we're (thankfully) forced to have no map contacts in-game, has anyone any experience with using a real paper manoeuvring board to plot intercepts and solutions?

I can't find a UK supplier, though I'm sure there are some, but the boards are double sided thick paper and come 50 to a pad for about $13. That's 100 plots.

Sounds cool to me.

Or are there better charts to use?

Sean C
04-11-19, 01:11 AM
I have used them quite a lot. I have a pad of them next to me as I type this, actually. Personally, I think they're great. They can be used to solve all sorts of maneuvering problems - even very complex ones.


One thing to keep in mind, though, is that you don't really need a pre-printed maneuvering board to do the plotting. It makes it convenient, but you can do the exact same plots with a ruler, compass and a pair of triangles or parallel rule on plain or graph paper. Celestial navigation plotting sheets can also be used.


If you haven't already read it, the maneuvering board manual (https://msi.nga.mil/NGAPortal/MSI.portal?_nfpb=true&_pageLabel=msi_portal_page_62&pubCode=0008) (chapter 6) is an excellent resource for learning many of the things you can do.


I can provide you with a link via PM to a high-resolution scan of a maneuvering board if you are interested. I don't want to make it public because I am acquainted with a gentleman that sells the pads and I am also unsure of any copyright issues.


Cheers!

Pisces
04-11-19, 11:49 AM
I think there is a scan of a maneuvering board sheet somewhere in the downloads section.

Nope, it's a (formerly known as Google) Sketchup template:

http://www.subsim.com/radioroom/downloads.php?do=file&id=3708

I do have a scan of a maneuvering board sheet (US Defence Mapping Agency) in my private collection (no doubt picked up somewhere in subsim forums) as .png file, 1939x 2003 pixels. But you'll have to fiddle with scale to get it right on paper.

Elphaba
04-11-19, 01:23 PM
Thanks for all the great info; unfortunately all these are imperial though right? So the nomograph won't work, without additional conversions from yards to meters and the inaccuracies that will bring.

@Nathanial B - I'd love to chat more about this with you, I'll PM you.

@Pisces - thanks for the link - I'll take a look.

bstanko6
04-11-19, 01:40 PM
Got my maneuvering board pad at amazon.com.

Elphaba
04-11-19, 01:48 PM
Got my maneuvering board pad at amazon.com.

Are you using it? Has it helped? What's the pros / cons so far?

Sean C
04-11-19, 11:54 PM
I think there is a scan of a maneuvering board sheet somewhere in the downloads section.


When posting the link to the manual above, I noticed there is the option on that page to download an image of the maneuvering board in two different sizes.


Here is the link again (https://msi.nga.mil/NGAPortal/MSI.portal?_nfpb=true&_pageLabel=msi_portal_page_62&pubCode=0008).

Topo65
04-13-19, 12:15 PM
Just a reminder: Aaron Blood's MoBo :salute: (http://www.subsim.com/radioroom/downloads.php?do=file&id=648)

gutted
04-13-19, 03:13 PM
One thing that has always irked me about maneuvering board/radar plotting tutorials on like youtube etc. is that after they convert the targets relative motion to true motion they say "and that's the targets true course".

That's only true if your course was 000. They never mention that it needs to be converted to take into account your own true course. Or when they DO try to show an example that doesn't have you on 000 (which is an extremely rare find on youtube), they never mention that the bearings plotted need to be bearings relative to your course (and not your nose) when plotted on the moboard for it to come out corrrectly.

Sean C
04-13-19, 05:50 PM
Just a reminder: Aaron Blood's MoBo :salute: (http://www.subsim.com/radioroom/downloads.php?do=file&id=648)

I thought about mentioning that, too. It's a really neat tool and searching for it is actually how I ended up here. However, the OP mentioned that he doesn't like using a mouse for plotting. IMHO, a paper MB is faster and easier to learn and use.

One thing that has always irked me about maneuvering board/radar plotting tutorials on like youtube etc. is that after they convert the targets relative motion to true motion they say "and that's the targets true course".

That's only true if your course was 000. They never mention that it needs to be converted to take into account your own true course. Or when they DO try to show an example that doesn't have you on 000 (which is an extremely rare find on youtube), they never mention that the bearings plotted need to be bearings relative to your course (and not your nose) when plotted on the moboard for it to come out corrrectly.

Maneuvering boards are meant to be used with true bearings, not relative. Many radar displays on commercial and navy vessels are in a North-up orientation. That means that all bearings displayed are true. Relative bearings can be determined easily after the relative motion problems are solved. When using true bearings, the course of your own ship or the heading (the direction the "nose" [bow] is pointing) doesn't matter when plotting contacts. The vector triangles are always drawn using your own ship's true course and speed. The result will always be the contacts true course and speed.

Oddly, a quick scan of the maneuvering board manual didn't turn up any mention of this - although it might be in there, somewhere. What [I]is mentioned in some problems is the need to determine relative bearings as part of the solution - implying that true bearings are being used.

I don't recall watching any YouTube examples of how to use a maneuvering board, but perhaps the makers of those videos are unaware of this fact. In any case, I agree with you that this should be explained.

Elphaba
04-13-19, 08:02 PM
OP mentioned that he

She.

:Kaleun_Salute:

Sean C
04-13-19, 09:59 PM
:oops: Apologies.

Elphaba
04-16-19, 12:10 AM
Just adding this as it's pertinent, and to keep everything in the same place:

http://www.subsim.com/radioroom/showthread.php?t=240739