Ground Radar Not Accurate

[Avio]

Trying out the JDAM using AGR but found that map image objects' locations seems to show up some inaccuracy. Small targets like tanks most time are likely to be missed by a few meters. Mapping using from 30 nm or less, altitude about 26,000 ft. Using EGI, which I understand do not need PVU updating. Was on NTTR map. Accuracy is perfect when using target Setpoint transfer method.

Anyone else encountered this?

 

 

[Rainmaker]

Coords vs designation and altitude errors. What you are describing would be expected outcomes when trying to hit small things with a radar like that. 

[nickos86]

Note, there is not digital ALT map correlated to the RDR for the 15E. If you designate a target while the waypoint you fly to (via UFC) or picked up in the RDR is far from the designation - you'll get a large ALT error because the plane will try to interpolate the ALT.

 

[jaylw314]

5 minutes ago, nickos86 said:

Note, there is not digital ALT map correlated to the RDR for the 15E. If you designate a target while the waypoint you fly to (via UFC) or picked up in the RDR is far from the designation - you'll get a large ALT error because the plane will try to interpolate the ALT.

 

I think the designation uses the elevation of the target point or sequence point in PB17, not the UFC

Edited December 20, 2023 by jaylw314

[nickos86]

if you got something in PB17 - it will use it. Else - UFC

[jaylw314]

53 minutes ago, nickos86 said:

if you got something in PB17 - it will use it. Else - UFC

Ooooh, so when it says 'SP' for sequence point, it uses the one from the UFC?  That makes sense

[Rainmaker]

Answer is certainly ‘it depends’. Beyond that, simple things like squishing a big area into a small display screen creates easy opportunities for error. Couple that together, very easy to not score hits on small targets. Even more so when you dont really have any proximity effects in DCS.  Asking for direct hits on targets with that method repeatedly is setting a bar a lot higher than it should be.  

[Avio]

Thanks much, folks. I am fully aware about the altitude use via PB17 and such, and had intentionally set up the steerpoint right on the same elevation ramp area where some tanks were deposited. Those tanks were pre-marked as targets waypoints too. When showed up on radar, it was clear the triangular target points just do not coincide with the radar image of target objects, being offset by a little, thus the JDAM missing by that little bit. But when target points were transferred to JDAM, the hit-rate was 100% spot-on all the time.

Could it be that from 30nm and at 26,000 ft and offset to 20+ to 30+ off nose the radar paint could not produce the best accuracy? At 30nm or less, would 20,000 ft be a better choice? Anyone tried that?

 

 

[Avio]

Okay folks, here's the real meaning of knowledge / skill atrophy ... actually I knew the answers, but been too long away from flying the eagle. So it is all about the "squint angle", best keeping to 2 to 10 degrees, if I got that right. That would mean coming in at 30nm / 20k ft or 20nm / 15k ft, with off-nose angles of 30 to 40 degrees. I just tried that and now all hits were spot on using radar, even for tiny tank targets. Hope that helps someone along.