GBU-38/31 accuracy vs GBU 10/12.

Hey folks,

so i have been dropping many, many gbu's over the last couple of days to figure out which weapon of the A-10c arsenal i want to use for what target and in what situation. Although i think i understand how to achieve a pretty acurate Spi to feed precise gps coordinates to the gbu-38/31 on release, i opted for a test scenario which hopefully eliminates human error. So in the editor i placed the 476th target circle B and placed a waypoint (giving me spot on coordinates) on it at zero altitude (it changes the elevation level to whatever altitude there actually is automatically). Clear skies and zero wind at all altitudes to further eliminate adverse influences.

Even under these 'optimal' conditions, the gbu-38/31 still more often than not miss by 2-6ish meters when i drop them in crrp mode on that afore mentioned waypoint. Yes i know, the manual states that these gbus are accurate roughly to about 10m. Gbu 10/12 on the other hand are a perfect hit every time if i make no mistake settings things up correctly.

So, i did read Eddies post about the differences between the real world thing and the dcs representation. Anyway, so are the lgb's in dcs more precise than the gps bombs and is there nothing i can to about that '5ish meter' spread of the gps guided bombs, or can i do something to make it as good as the lgbs? What yours experience lately with these boms in 1.5/2.0?

What SPI exactly are you sending to the JDAMs?

In DCS Paveways do seem to be more accurate (often perhaps too accurate), so yes for accuracy alone the GBU-12/10 does tend to be better in sim.

@ Gliptal
The 'spot on' waypoint set in the editor was my spi for the tests. Drop height was well above 10.000 feet. It really seems not to matter whether you have a perfectly lined up release or release it barely in the 3/9 line. It always finds the target alright even from pretty off angles, but there's that dispersion of impact points that makes a consistent hit on a tank and thus kill of a hardend target a game of luck.

@ Eddie ...in real life, should these bombs hit consistently within a couple of feet, or is the end result that dcs models similar to the accuracy of the real thing? I always thought that military gps was supposedly of a good deal higher resolution, hence accuracy should be in the couple of feet ballpark. Or what i am trying to say is: the bombs can control their flight path pretty well, correcting very well for off angles and such. But they still miss in the end. So just out of curiosity: how big is the possible impact area of a L/L or UTM coordinate in square feet. Could that be the explanation for the spread?

Provided the transfer alignment is up to spec, and the weapon is released within LAR then unless there is a malfunction it'll be within a couple of feet of the target point.

DCS JDAMs are "a bit shit".

Aight, thx for the info. I wasted too much time on trying to get them on target already:yes:

I've resorted to using the GBU-38 on light armor, they get the job done pretty reliably. But on anything thick they can be quite unreliable.

Yeah, noticed that too. When i was testing the 31/38s, i placed trucks and apc's as targets in the editor and watched the impacts from above. And it does a good enough job on those. But once i checked the actual impact points via F6, i saw what was going on with that spread.

It's so weird to follow the bomb. It's as if the GBU-38 is on target until a couple of seconds, then it veers of a little bit. I may be imagening this behaviour though :)