UTM Coords Explained

[Succellus]

Don t cry strongharm you got rep...lol

I m very happy you brought that, i was always curious about navigation, now with you and effte, even if not knowing all, i have a fair idea and how it works and would be able to read a map with due time (half an hour lol)

 

Effte i cannot rep you anymore it seems. Crappy system.

[effte]

I mean.. all I have to do is to punch in the coords in UFC right? The hogs' TAD should take care of the rest.. right?

 

Yes. Do read the caveats section, more in depth here, as that will bite you otherwise, and to fully grasp that bit you will probably need to at least have the basics down, but in general you can operate the Hog on a "push the right button in the right sequence" basis. That cuts down the learning curve and gets you up there doing things.

 

Then, while you are having fun, figure out what the buttons do and why as you go. It becomes infinitely more rewarding and less confusing.

[StrongHarm]

+1 .User:Succellus .Comment:For bringing this on even if not that right.

 

ha. ha. Succellus! Very f'in funny :)

[Fish]

In the graphic, the point used could be described as, with decreasing precision,

WC8081751205

WC80815020

WC808512

WC8051

WC85

 

The 0 in 067 can NOT be dropped. No way, never. DCS drops leading zeroes on the eastings. This is a bug, which always gives incorrect coordinates and which can give unusable coordinates if there are two leading zeroes. To use coordinates with leading zeroes dropped in the CDU, you need to reinsert the missing zero. Odd number of digits -> Assume missing leading zero. Double leading zeroes missing? You have no way of knowing something is amiss and you're basically screwed.

 

Been to this thread before but had not the patience to grasp it. A 'UTM' post has lured me back now.

 

Question remains for me.

if i know the precision is 6 digits, and i only get a call of 4, then I just add the leading zero's in the correct positions in the string.

 

But say the call is 6 digits precision, but I only get 5 digits.

First i know that a a leading zero is dropped. But which one, the easting or the northing. is that the nub of the problem ?? Is this likely to happen in DCS ?

[Speed]

But say the call is 6 digits precision, but I only get 5 digits.

First i know that a a leading zero is dropped. But which one, the easting or the northing. is that the nub of the problem ?? Is this likely to happen in DCS ?

 

There is at least a 10% chance this will happen. I need to get off my ass and finally fix this- I'm pretty sure I know where the bug is- it's in line 108 of C:\Program Files\Eagle Dynamics\DCS A-10C\Sounds\Speech\NATO.lua, this line where they convert MGRS to a string:

 

C:\Program Files\Eagle Dynamics\DCS A-10C\Sounds\Speech\NATO.lua, line 108:

str = str..base.tostring(MGRS.Easting)..base.tostring(MGRS.Northing)

Basically, what they are doing in this line is that they are converting the MGRS coordinate numbers into text that can be displayed on your screen. However, note that they make no provision in this line to append the leading zeros in this conversion. I guess I can make this fix tonight and upload a mod, assuming I'm right about this being where the "5 digit grid" bug arises from.

 

Anyway, based off of this line of Lua, that means that if you get a five digit grid such as:

 

34562

 

it can be either

 

034562

 

or

 

345062

 

A four digit grid would be 10X rarer than a 5 digit grid. On average, you should expect to see a four digit grid 1 out of 100 times JTAC gives you a MGRS coordinate. But if you DID see a four digit grid, such as 2173, then it could be any of these:

 

002173

 

021073

 

217003

[Speed]

Ok, I THINK I fixed the occasional "5 digit grid" problem with JTAC MGRS coordinates. If someone could try this out, I'd be appreciative. I can't ever get the JTAC to give me targets in any JTAC missions I build. Maybe I need to make the JTAC invisible, invincible, and nearly on top of the enemy...

 

Anyway, to install this new file:

 

1) In C:\Program Files\Eagle Dynamics\DCS A-10C\Sounds\Speech (I think this is the right directory, I'm not at my flying machine anymore), rename "NATO.lua" to "NATO_original.lua" (or anything you like, all that matters is you rename it).

 

2) Paste in the new NATO.lua file attached below.

 

3) Now go fly and see if

a) JTAC gives you coordinates, and

b) That the JTAC will now correctly give you coordinates when there is a leading zero in the easting or northing.

 

Anyway, anyone testing this will receive... well, I guess my appreciation, for what little it's worth... I am no longer at my flying machine anymore, and as I already said, last time I tried to make a mission with a JTAC, the bastard would only ever tell me "no targets available, you may depart". I'll try it again tonight if no one is able to give me confirmation that this fixed the problem.

 

Anyway, if this works (it definitely should fix a bug somewhere at least), I can upload it as a Modman pack as well.

 

If anyone is actually curious about what I did in NATO.lua open up the spoiler below.

 

 

The only change I made to NATO.lua, besides adding some comments, was to change line 108 from:

str = str..base.tostring(MGRS.Easting)..base.tostring(MGRS.Northing)

 

to this:

str = str .. base.string.format('%0' .. base.tostring(accuracy) .. 'd', MGRS.Easting) .. base.string.format('%0' .. base.tostring(accuracy) .. 'd', MGRS.Northing)

 

In the previous lines of NATO.lua, the number values referenced by MGRS.Easting and MGRS.Northing have already been rounded and divided by the appropriate amounts. What this line of Lua does is instead of just blindly converting those numbers to a string of characters, it converts those numbers to a string of characters that must be accuracy characters in length (where accuracy is a passed in number variable that is the requested number of digits in each northing and easting part of the string), with leading zero padding if the number of characters in each easting/northing is less than accuracy digits long.

 

NATO.lua

Edited October 20, 2011 by Speed

[Evil.Bonsai]

Worked!

 

"golf henry three five seven ZERO nine seven"

 

and again

 

"golf henry three five six ZERO nine four"

 

AWESOME!

 

and to make sure, went back and changed to old nato.lua and received

 

GH35797 for co-ordinates.

 

THANK YOU FOR FIXING THIS!

 

Notes: did not check any coords with a leading zero for first set, or zeros anywhere else. I just happened to have a short jtac mission that I knew had a leading zero on the 2nd set

regarding nvg use in trk file: modifed DMS down is NVG, modified TMS down is cdu. I get them confused sometimes. :/

fixed jtac.trk

Edited October 20, 2011 by Evil.Bonsai

[Speed]

Thanks, I also was able to test it and verify that it fixed the problem, as I finally got a JTAC working (apparently, FAC task + FAC- Assign Group task = bad), and tested it out. In my test mission, instead of "LN225" (I purposely crafted just about the worse-case scenario), JTAC now tells me "LN002025". I posted a thread in the Mods and Apps section here.

 

BTW... yea, you probably shouldn't bother trying to post tracks of the fixed behavior, it's not likely to appear fixed when replayed by someone who hasn't applied the fix.

Edited October 20, 2011 by Speed

[Evil.Bonsai]

 

BTW... yea, you probably shouldn't bother trying to post tracks of the fixed behavior, it's not likely to appear fixed when replayed by someone who hasn't applied the fix.

 

er....Doh! I think I knew that but forgot. I guess I could've converted to a movie file if I had thought about it. It's very short: just loaded the mission and contacted jtac immediately. Maybe a couple mins at most.

 

In any case, again, thanks for this.

Edited October 21, 2011 by Evil.Bonsai

[Fish]

Ok, I THINK I fixed the occasional "5 digit grid" problem with JTAC MGRS coordinates..................

 

Nice Fix :thumbup:

 

Sorry i could not check earlier, looks like someone else got there first with the 'northing' coordinate. And you checked both!! Below is example of 'easting' coordinate.

 

(Hmm, i'm thinking E longitude, and distance in bullseye calls.....)

 

 

[Sarge55]

Excellent. Thanks Speed...