LGBs more penetrating than JDAMs

[marcos]

When destroying an ammunition bunker with GBU-31s it took 3. Using MK-84s in CCIP it took only 2.

 

I thought that the difference may be the extra KE in CCIP delivery so I hit an ammunition bunker with 2 GBU-10s in CCIP, and they destroyed it. Then I tried 2 GBU-10s in CCRP and they still destroyed it.

 

Is there a reason why some 2,000lb bombs are more destructive?

 

Similarly 2 FAB-500 M62s and 2 KAB-500Krs will not destroy an ammo bunker but 4 FAB-500M62s will.

[Pyroflash]

Doesn't make much sense (It seems like a really weird bug). Did you retry the tests with the bombs ensuring they hit in the same places, or did you just try the GBU-31's once?

 

Similarly with the Russian bombs.

 

Can you post a track illustrating your issue?

 

I'm looking into it right now, you meant the ammunition depot right?

 

Yeah, definitely able to reproduce this issue 100% of the time. GBU-31's are a little underpowered, or something else is in the works behind the scenes.

 

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Well, I think I figured out the Russian part of the problem. In \\Config\Weapons\warheads.lua, the KAB-500Kr and FAB-500M62 both have different explosive values for different warheads despite them being based off of the same bomb.

 

The American bombs still have an issue however. The bombs reference the same warhead (Mk-84) as they should, but somehow produce differing results.

 

Just shooting in the dark here, but by some coincidence the GBU-31 (or any GPS guided munitions for that matter) are the only ones not referenced in \\Config\Weapons\bombs_table.lua

 

maybe this could be a contributing factor?

Edited August 21, 2012 by Pyroflash

[marcos]

The GBU-31s I've repeated several times as part of a mission I built. It seems to be fairly finely balanced though because 2 hits and a near miss will also destroy the ammo bunker.

 

Also verified with FAB-500 vs KAB-500 too.

 

I'm looking into it right now, you meant the ammunition depot right?

Yes.

 

The GBU-10 is 19lbs heavier than the GBU-31 according to wiki and the Mk-84 is 3lbs heavier. The straw that broke the depot's back?

Edited August 21, 2012 by marcos

[Pyroflash]

Yes.

 

The GBU-10 is 19lbs heavier than the GBU-31 according to wiki and the Mk-84 is 3lbs heavier. The straw that broke the depot's back?

 

Regardless of what the wiki says, I don't think this is the issue as the weapons tables list all of the bombs as having the same mass (894 (no units given, but probably in Kg)), except for the GBU-10 which is listed as 900 mass.

 

In the table though it is listed differently than the data file. Makes me wonder, though I am guessing that it is the table that defines it whilst the data simply describes it. If that is the case then the Mk-84 gets bumped up to 900 Kg, and the GBU-10 hits up a little above that. Can't speculate at all as to the state of the GBU-31 however, as it is non-existent in that table.

 

Err.. This is probably as far as my knowledge can help, sorry that I couldn't do more to solve the problem.

Edited August 21, 2012 by Pyroflash

[JB3DG]

I have noticed that GBU-10s/12s tend to accelerate (naturally this is what you would expect) when on the final dive at the target. But the GBU-31 slows down...dunno why cuz that seems to defy physics.

[JorgeIII]

May be its related with ballistic coefficient an final energy at impact?

GBU 10 and GBU 12 (Laser guided) drop in game much faster than GBU 31 and GBU 38 (inercial and GPS guided). This difference in falling velocity doesnt looks right.

Energy = M.V 2 (square velocity). So GBU 10 & 12 will have much more kinetic energy.

 

Penetration is related to Energy on impact, bomb design (materials and shape, tipe of point, like FMJ vs hollow point and HE vs AP) and fuse time.

 

Most likely is a bug.

[BlueRidgeDx]

Regarding impact velocity: it's actually "by design", since JDAM don't use the AFM like LGBs do. It's a known issue, and is on "the list". If and when it gets "fixed", I won't hazard a guess.