[INVESTIGATING]JDAM/JSOW hit targets when off parameters

[Gierasimov]

Hi all,

 

In the attached tracks you can see how releasing JDAM or JSOW outside of parameters still produce valid results.

 

JDAM: TMR 7 + QUAL 05 MAR results in direct hit - neither IN RNG nor good alignment was needed.

 

JSOW: similar to above, even "better" with TMR 27 and ALN QAL 07 UNST, still direct kills.

 

(PS JSOW destroyed two targets but that's a separate issue with the new China Pack IFV - already reported.)

JDAM - IN RNG.trk

JSOW - IN RNG.trk

[BIGNEWY]

Hi Gierasimov

 

I am investigating this, but I will need some time, when I know more I will reply.

 

Thanks

[Gierasimov]

Hi BIGNEWY,

 

Sure thing. Let's see what happens.

 

EDIT: Just tested one more time - Flying at 25K MSL / Mach 0.98 / ALN QAL 03 GOOD / TMR 25 - released single JSOW that reached the target while still outside of max range circle on HSI.

Edited September 5, 2019 by Gierasimov
Tested again

[NeMoGas]

I've been dropping GBU38 with a TMR of 10 seconds for a while now. Been capable of scoring hits from 27nm if no mountains are in the way. Also I noticed alignment seems to be unnecessary as well, but I just chocked that up to INS being WIP/nonexistent.

[BIGNEWY]

As far as I aware TMR is calculated with optimal weapon data for delivery, there may well be some leeway outside of maximum range.

 

However the alignment issue I am not sure and will need to check.

[Gierasimov]

Now, reading about it I know better than before I posted.

If this weapon is not aligned completely it does not invalidate the shot, but it should be expected that the weapon won't be accurate.

 

In our case above weapon is in fact accurate so this is the only thing which is not simulated currently, so maybe after its development is finished we will see an improved simulation of GPS / INS munitions.

[BIGNEWY]

Now, reading about it I know better than before I posted.

If this weapon is not aligned completely it does not invalidate the shot, but it should be expected that the weapon won't be accurate.

 

In our case above weapon is in fact accurate so this is the only thing which is not simulated currently, so maybe after its development is finished we will see an improved simulation of GPS / INS munitions.

 

Possibly, I am not sure if poor alignment for munitions is modelled in DCS and if it is what margin of error should we see. The people with the answer are not available at the moment, as soon as I get an answer I will let you know. :)

[Harker]

I remember reading that GPS guided munitions continue aligning even after launch in a similar way to IFA for the INS. So if the alignment quality it's close to GOOD before launch, it might have time to reach a good alignment during the bomb's flight. The way I see it, this should work only if the alignment is almost complete before launch.

 

A good test would be flying in LAR and then selecting a JDAM/JSOW and launching immediately, without any alignment before launch.