How do I use JSOWs?

Hi all,

after several tests with JSOW in different situations and environments, it seems they have an hard time hitting target situated more than a bunch of feets above sea level.

How to reproduce:

the attached mission is a copy of the standard weapon training in Nevada, with just initial distance, altitude and loadout modified. Waypoint 2, 3, 4 and 5 are positioned on top of 4 trucks to easily save the coordinates in TOO.

jsow_accuracy.trk

Nevada FA-18C JDAM Practice.miz

Hi all,

after several tests with JSOW in different situations and environments, it seems they have an hard time hitting target situated more than a bunch of feets above sea level.

 

How to reproduce:

the attached mission is a copy of the standard weapon training in Nevada, with just initial distance, altitude and loadout modified. Waypoint 2, 3, 4 and 5 are positioned on top of 4 trucks to easily save the coordinates in TOO.

I did not watch the tracks. Did you cross check the target altitude with the one entered into the JSOW??

I did not watch the tracks. Did you cross check the target altitude with the one entered into the JSOW??

yes I did, I've tried to change just the target altitude after the coordinates are copied from the WPs with TOO but the bombs are going off anyway.

If I insert the coordinates manually the bombs are right on target so I suppose this happens when the target coordinates are copied from a WP.

Anyway this thread was opened in the bug section, but they moved and renamed it without even answering, so I guess it doesn't make sense anymore.

yes I did, I've tried to change just the target altitude after the coordinates are copied from the WPs with TOO but the bombs are going off anyway.

 

If I insert the coordinates manually the bombs are right on target so I suppose this happens when the target coordinates are copied from a WP.

 

Anyway this thread was opened in the bug section, but they moved and renamed it without even answering, so I guess it doesn't make sense anymore.

It is not in the bug section because user error could still be an option. If the altitude is correct, make sure, the format of the coordinates is still correct when entered.

It sounds so far as if you've got 4 way points at some altitude above the surface and you're entering that data into the JSOW for TOO, then altering the target elevation.

Chuck's guide has a good tutorial for this, and it shows elevation entry for the WPTs at target elevation. Have you tried that?

yes I did, I've tried to change just the target altitude after the coordinates are copied from the WPs with TOO but the bombs are going off anyway.

Nineline has said TOO co-ordinates should not copy to PP for JDAMS, I'd guess the same is true for JSOWs.

Taking control of your track but using TOO, and a single JSOW, it landed within 87 ft of the target vehicle (at WP1), which seems a little off as JDAM CEP is ~13m (45 ft) but perhaps was due to the JSOW's shallow dive angle.

I'm not sure if a bug or user error but found I couldn't drop a second JSOW on a second TOO designated target/waypoint. WIP bugs like these are why I've been waiting for the Hornet to mature but YMMV.

If I insert the coordinates manually the bombs are right on target so I suppose this happens when the target coordinates are copied from a WP.

It sounds like you are using JSOWs as ED intended.

Tested in Open Beta 2.5.5.39003

It sounds so far as if you've got 4 way points at some altitude above the surface and you're entering that data into the JSOW for TOO, then altering the target elevation.

Nicely spotted, it seems the ME doesn't let you set 0 feet AGL now ?

Setting a waypoint's height to 0 ft AGL, the ME now defaults to 98 ft (30 m) as a minimum value.

So the OP looks to have tried setting his WP's on his targets at 0 ft AGL but the ME has enforced 30m AGL minimums.

To create a waypoint at 0 ft AGL, you now need to select MSL and enter the terrain elevation i.e. the value read by the mouse cursor so WP 2 = 4580 ft MSL

Note: to set a value lower than 4678 MSL, you need to switch from AGL and then change waypoints for the AGL -> MSL change to take effect.

Tested in Open Beta 2.5.5.39003

Nineline has said TOO co-ordinates should not copy to PP for JDAMS, I'd guess the same is true for JSOWs.

Thank you Ramsay, I've missed that post from NineLine and that's enough for me to stop trying to copy coordinates between TOO and PP. It always worked and as I've never been on a real hornet I've just supposed that was an intended feature....

Taking control of your track but using TOO, and a single JSOW, it landed within 87 ft of the target vehicle (at WP1), which seems a little off as JDAM CEP is ~13m (45 ft) but perhaps was due to the JSOW's shallow dive angle.

 

I'm not sure if a bug or user error but found I couldn't drop a second JSOW on a second TOO designated target/waypoint. WIP bugs like these are why I've been waiting for the Hornet to mature but YMMV.

Thanks also for taking some time to review the track, I think the difference in the errors is related to the fact that is impossible to set a WP exactly on the ground, the minimum altitude above ground level is always 89ft, so the shallower the dive angle the bigger the error. The only weird result I had was that even when I tried to correct the copied altitude manually the bomb went off anyway.

Nicely spotted, it seems the ME doesn't let you set 0 feet AGL now ?

 

Setting a waypoint's height to 0 ft AGL, the ME now defaults to 98 ft (30 m) as a minimum value.

 

So the OP looks to have tried setting his WP's on his targets at 0 ft AGL but ME has enforced 30m AGL minimums.

 

To create a waypoint at 0 ft AGL, you now need to select MSL and enter the terrain elevation i.e. the value read by the mouse cursor i.e. so WP 2 = 4580 ft MSL

 

Note: to set a value lower than 4678 MSL, you need to switch from AGL and then change waypoints for the AGL -> MSL change to take effect.

 

Tested in Open Beta 2.5.5.39003

Thanks for the suggestion, I haven't tried with MSL yet, I'll give it a go tonight to check if there is any difference.

... I haven't tried with MSL yet, I'll give it a go tonight to check if there is any difference.

There is, 4 direct hits using your release method, with very little error (46ft, 32ft, 16ft and 15ft).

There is, 4 direct hits using your release method, with very little error (46ft, 32ft, 16ft and 15ft).

I did some tests yesterday and I can confirm using MSL with the ground altitude does the trick, I had 4 almost direct hits. One weird thing is if you're switching ftom AGL to MSL, the altitude is still stuck to ground level + 98ft and you can't set anything lower, unless you switch to another waypoint and you go back again on the previous.

All working now, thanks again for your help

What I do for setting waypoints on the ground is simply entering 0 (in MSL), and it automatically snaps back to terrain elevation (any value lower than elev will do that in fact). I frankly think I had never even tried the AGL option until just now ! And indeed, it seems it doesn't let you go to 0 AGL.

What I do for setting waypoints on the ground is simply entering 0 (in MSL), and it automatically snaps back to terrain elevation (any value lower than elev will do that in fact). I frankly think I had never even tried the AGL option until just now ! And indeed, it seems it doesn't let you go to 0 AGL.

I've been doing the same thing since forever and never had issues. I think I only touched AGL a few times, when planning low level insertions or some heli flights. Setting MSL to 0 in the ME works perfectly for ground targets. Additionally, if your next target is at a higher elevation, the ME will automatically correct to the new terrain elevation.

Sorry, but I can't get over the fact, that ED's former implementation with getting 4 target's coordinates by TGP to the 4 PP slots, hold the pickel and get 4 hits is/was better than the real thing!?

Got my stable update today and it feels like losing the best thing about TGP and JSOWs.

Ain't there any hope to get this back?

Have I missed a procedure to attack e.g. 4 stationary tanks simultaneously with TOO->PP?