Jump to content

JSOW - How to counter wind?


Recommended Posts

I've been testing the AGM-154A and its very inaccurate with some wind the BLU had 60m of drift.

 

How can I compensate the drift of the wind? I guess I should take into consideration the time they take to fall and direction and speed of the wind, then I should use the meterstick to compensate? It looks like a lot of work, plus a correction of 60m on the TGP its very difficult specially at medium-long ranges.

 

I also had this problem with the CBU-97 but the SFW are more effective.


Edited by Ignition
Link to comment
Share on other sites

Hmmm, lower HOF should reduce drift. I would think 1M$+ weapon with INS would detect wind drift the same as F-16 can and apply offset to dispense point. I'm trying to think of a calculated OAP would allow you to put TGP on target and have missile go to offset target. OAP not modeled yet though.

 

What are your ROB and HOF settings?

Link to comment
Share on other sites

Posted (edited)

Didn't change them, 2000ft and 5nm. I did more testings and its really hard to hit anything.

It's not possible to modify those parameters in this version.


Edited by Ignition
Link to comment
Share on other sites

I wasn't able to change the settings. The CNTL button did nothing.

 

I too have been playing around with the JSOW and did note mostly f-kills and only some k-kills on SA-11 sites. The only way to find out is to observe the enemy afterwards for BDA. It would be nice to see it in the recap just to get awareness of the JSOW effectiveness. 

 

AFAIK the wind should be modeled in the terminal ballistic calculations of the blu-97. Since it's absolutely impossible to Kentucky windage at the distance you normally employ a AGM-154A.

 

Link to comment
Share on other sites

That is good. Best test I think is to run the exact mission twice with and without wind and record positions of dispenser opening in both. If weapon compensates the positions will be different.

Link to comment
Share on other sites

Posted (edited)
1 hour ago, Frederf said:

That is good. Best test I think is to run the exact mission twice with and without wind and record positions of dispenser opening in both. If weapon compensates the positions will be different.

 

I tested with and without wind, the wind makes the BLU to drift a lot. Without wind they go to the target.

 

I've tried to compensate the wind but its so difficult, its an useless weapon as of right now.

3 hours ago, Sinclair_76 said:

Tested the AGM-154A with 30kt winds and the bomb is tracking and dispersing upwind but the BLU-97''s drop right on target. It works as advertised.

 

 

 

 

So if I drop them upwind they go to the target? I didn't know. I will test it.

 


Edited by Ignition
Link to comment
Share on other sites

11 minutes ago, Ignition said:

 

I tested with and without wind, the wind makes the BLU to drift a lot. Without wind they go to the target.

 

I've tried to compensate the wind but its so difficult, its an useless weapon as of right now.

 

So if I drop them upwind they go to the target? I didn't know. I will test it.

 

 

I had a steerpoint over the tgt with the correct altitude set as well. Slaved the tgp to the stpt and let the JSOW do the rest. I didn't compensate for the wind, the AGM did it by itself as it should.

 

Lot of people forget to enter the correct altitude for preplanned targets. That will introduce variables which are subject to wind drift.

 

Link to comment
Share on other sites

52 minutes ago, Sinclair_76 said:

I had a steerpoint over the tgt with the correct altitude set as well. Slaved the tgp to the stpt and let the JSOW do the rest. I didn't compensate for the wind, the AGM did it by itself as it should.

 

Lot of people forget to enter the correct altitude for preplanned targets. That will introduce variables which are subject to wind drift.

 

 

If I shoot the AGM154 without wind it goes correctly to the target, If I put some wind with the same mission the BLU drift away of the target.

Link to comment
Share on other sites

No wind:

Dispenser opens at 65s after release, 1650' MSL, -26 pitch, 635kt N41 50.536' E41 47.328' terminal heading 084T

 

Wind 20 kts 33ft, 43kts at 1600/6600/26000 heading 180 to:

Dispenser opens at 63s after release, 1555' MSL, -24 pitch, 638kt N41 50.545 E41 47.313 terminal heading (not track, orientation of the JSOW nose upwind) 079T

 

The different in latitude of 0.009' is about 17m which is not a lot. The CEMs did hit nicely on target despite the crosswind though. Maybe 17m was enough. I also wasn't super careful that the line between release point and target was exactly the same. I think the steep-fast approach makes wind drift less apparent. Trying again near maximum glide range which should be slower and have a more dramatic result.

 

Same wind as test #2 at max JIZ range +3s. Speed 416kt, 080T, ~1533' N41 50.664 E41 47.348.

 

At about 3nm to target the JSOW maneuvered upwind. CLEARLY the dispenser released upwind about 600' north of the previous ground track. The CEMs drifted dramatically downwind and hit the assigned location well.

 

Conclusion: Not exhaustively tested but in both tests with crosswind the CEMs landed on assigned target and dispenser flew upwind compared to the no wind condition. Unless there are some odd situations the compensation doesn't perform well for I'd say performing well.

  • Thanks 1
Link to comment
Share on other sites

Posted (edited)

Tested again, it seems the AGM did compensate although too much this time. Tried several times and they ALL hit to the NW of the target in the same spot.

 

Dd2q5Xi.png

jsow 2.trk

 

 

Tried again and they don't hit the targets at all, tried against the wind and they all drifted a lot to the south.


Edited by Ignition
Link to comment
Share on other sites

No idea. F-16 in DCS has big problems with non-standard atmospheric pressure and system altitude. In your tests on Syria can you confirm that TD box is not artificially above/below actual target location?

Link to comment
Share on other sites

Posted (edited)
58 minutes ago, Frederf said:

No idea. F-16 in DCS has big problems with non-standard atmospheric pressure and system altitude. In your tests on Syria can you confirm that TD box is not artificially above/below actual target location?

 

It was at ground altitude, I always put 0ft on the mission editor to be sure its at ground altitude, in this case 1611ft.

 


Edited by Ignition
Link to comment
Share on other sites

What was the QNH? I find the CEMs land long (most beyond the target, few before) but otherwise left/right which was up/down wind was OK. I only tested a 10m elevation "X" runway on Caucuses.

 

Winds are different at different levels. DCS doesn't do winds AGL but MSL so at high elevations on the surface are the same as that same MSL altitude high above the ground elsewhere.

I just tried an attack at an elevation of 5400' with wind speeds 20kts 10m, 43 kts 500m and up. CEMs landed about 65m upwind closest approach if Tacview is to go by. Maybe the wind sampling or drift analysis isn't perfect.

Link to comment
Share on other sites

I tested the setup at high alt no wind and with a 30kt crosswind. Both times weapon effect, dead center no wind and almost center with 30kt wind. Target was at 10075'. Final run I put in the stpt / target elevation at 11000', roughly 1000' too high. Hypothesis was that blu would be deployed 1000' higher and therefore subjected to more wind drift. Turned out to be true. So for better target effect be sure to verify target altitude and stpt altitude to be the same.

 

NO WIND

 

Screen_210723_081336.jpg

30kt WIND

Screen_210723_081725.jpg

30kt WIND / INCORRECT ALT

Screen_210723_083923.jpg

TEST JSOW HIALT 30ktW - wrong alt.trk TEST JSOW HIALT 30ktW.trk TEST JSOW HIALT NW.trk


Edited by Sinclair_76
Link to comment
Share on other sites

 Share

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...