need track replay JTAC coordinates potential problem

[84-Simba]

Hi !
To separate from another problem I'm creating a new thread.

I set a JTAC in a Stryker (TOW) and it has the capability to actively lase.

When it gives me the coordinates, I get 8 digits and an altitude ... but if the coordinates are completely off, the altitude is true and it lases at the right target.

When I say the coordinates are off, they are off by 300m at least.

Let's say Axeman picks up a general area coordinates and do the precise targeting with the laser ...
 

What I observed is that he gives me the altitude of the real target but and not the true altitude of the point he gave me.

Like - 56572736 at 230ft.

Enter those coordinates and the Apache will give you 252ft.
Check on the f-10 map and the Apache is right ; the TADS looks where it should and the altitude matches.

And if you LST the TADS to where Axeman is lasing (the target) it is at 230ft.

So basically Axeman cannot give me more precise coordinates but is giving me the correct target altitude.

Is that supposed to work that way ?

[Lord Vader]

Hi @84-Simba

In this case we would like to ask you for a track to have a look at what you're saying is happening.

Just a short setup in Caucasus, nothing complex, if you can.

Thanks in advance.

[ShuRugal]

Have you verified that the JTAC is giving you the same zone number and grid letters as what you are currently flying in?

There are several regions on each game-map which have overlapping MGRS zones.  In one of these regions, sometimes the helicopter you are in will decide it's in one map, while JTAC might decide it's in another.

For example, see attached.  The map 37 T overlaps with 38T near Senaki.

Each 2-letter box (often called 'grid square') on an MGRS map is 100x100 km.  But notice at the edge of 37 T GG, the Easting grid stops at 4 (whereas it would ordinarily go to 9), and the easting for 38 T KM starts at 5, where it would ordinarily start at zero...

Well, if you grab yourself a paper (or PDF) copy of either of those charts, you'll find that they don't stop/start at those locations.  a map of 37 T GG will display the full 100x100 km, as will a map of 38 T KM.

the F10 Map (and other digital live-map renderings of UTM charts) will draw a cutoff line between those two charts aligned with true north for rendering those charts in a non-cluttered manner, but location designations across that border are still valid for either chart.

Now, I would HOPE that all units in DCS are using the same criteria for choosing which grid to reference when near a border, and it would make the most sense if they all respected the lines depicted on the F10 map.  However, I have seen cases where this very definitely is not happening.  I've seen my Apache say I am on one chart while the F10 map says i am on another, and both were correct when i correlated against a building on the map.

There's even a good example in one of the pre-packaged Apache missions where the information on the kneeboard shows a target point which across the border of the chart, but does NOT include the zone information.  If you just punch in the grid letters and easting/northing, the target point you input will be 50 km in the wrong direction.  (Though i haven't checked in a while, maybe that mission has been fixed?)

 

Anyway, that's my $2 on what's happening.  Verify that the full map information the JTAC is giving you matches, not just the 8 digit grid at the end.