GBU-39 Employment Issues
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For some reason I can’t seem to get the bombs to hit the targets. I ran missions in different campaigns and also created one. Here is what I am doing.
1. I do a recon of the targets in the mission editor.
2. I create steer points from 13 to 20 for each target. I have chosen both SAM and fixed targets like barracks just in case the SAMs move.
3. I save and load the DTE. Then load the DTE in flight.
4. I change to AG master mode and go into the SMS page and power on the GUB-39s.
5. I advance the steer point to 13 and line up for the target.
6. I leave the bomb profiles at default - I think I read if the azimuth is 0 then the bomb will directly fly to the target.
7. As soon as the GBU-39 is indicating RDY and I receive the JIZ indication on the HUD I begin pickling the bombs. Switch steer points, pickle another bomb, doing this until all bombs are dropped. All bombs are dropped within range parameters. The jet is also lined up with the targets.All the bombs miss, every time.
Any ideas?
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- Have you Cursor Zeroed?
- Made sure you do not have a targeting pod track on anything
- Double checked not just the steerpoint number but the actual coordinate
- Made sure the GBU-39s are completely aligned (aka A01 disappears, think you can get a RDY before it does).
- Are you dropping close to max or min range? Try a nice heart of the envelope delivery, something like .8 mach at 20 thousand feet, pointing at target and let’s say 12 nm range.
How far do they miss? Is it close or wayyy off?
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- Have you Cursor Zeroed?
- Made sure you do not have a targeting pod track on anything
- Double checked not just the steerpoint number but the actual coordinate
- Made sure the GBU-39s are completely aligned (aka A01 disappears, think you can get a RDY before it does).
- Are you dropping close to max or min range? Try a nice heart of the envelope delivery, something like .8 mach at 20 thousand feet, pointing at target and let’s say 12 nm range.
How far do they miss? Is it close or wayyy off?
They are way off. I usually drop between min/max range with the HUD indicating JIZ. I will try to fly it without the TGP or TGP off. I also usually take the HTS pod, but I am in the SMS page when I drop. I use the HAD to designate SAM radars so my wingman can suppress it with HARMS. If I am use PRE mode of the GBU-39s does the need to cursor zero still apply.
Re: the steer point/coordinates. I’ve seen references to Weapon steer point, so let me know whether I am doing this correctly. I go the editor and recon the target. A list of targets show up. I designate a target then advance the steer point to 13. Hit accept, then do the same for other targets and advance the steer point and accept for each target.
The steer points definitely load as they appear in the DED.
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Seems you are doing things right,
I leave the bomb profiles at default - I think I read if the azimuth is 0 then the bomb will directly fly to the target.
Don’t know about this though, in the manual I only found this applicable for SDB 's:
ATTACK AZIMUTH
0 TO 360 DEGREES
BLANKED FOR 0
ENTRY, VIS SUBMODEMakes me think zero is used for VIS mode, could be wrong though. I’m using the same procedure you use, but I always enter an attack azimuth and I never have problems hitting the targets.
send from my C6903
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If I am use PRE mode of the GBU-39s does the need to cursor zero still apply.
Yes! This is essential. Drop with SMS on one and HSD in other and make sure CZ has been pressed and is not highlighted. Maybe take a screenshot at your moment of pickle and post it here?
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“0” azimuth is the null value in which the SDB doesn’t attempt to fly any particular final approach azimuth in PRE. In VIS it never flies set approach azimuth regardless of setting.
PRE SDB goes after SPI similar to JDAM/WCMD. If you want to attack a steerpoint by coordinates then you want to be sure your steerpoint-to-SPI deltas are zero’d (CZ not reverse video). On the other hand if you want to direct the SDB toward your SPI which isn’t your steerpoint then you’ll have non-zero deltas. VIS goes after the HUD TDC box which I forget if that’s true SPI or just a temporary location for the purposes of SDB.
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7. As soon as the GBU-39 is indicating RDY and I receive the JIZ indication on the HUD I begin pickling the bombs. Switch steer points, pickle another bomb, doing this until all bombs are dropped. All bombs are dropped within range parameters. The jet is also lined up with the targets.
All the bombs miss, every time.
Any ideas?
Seems like you are doing everything right indeed, but 1 thing, are you sure you wait long enough for the GPS on the weapons to finish alignment? You should see “RDY” down in the MFD above OSB 13. Aside that, I will need to see a vid in order to understand what is wrong.
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are you sure you wait long enough for the GPS on the weapons to finish alignment? You should see “RDY” down in the MFD above OSB 13.
Can an INS weapon be released prior to alignment?
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Can an INS weapon be released prior to alignment?
Never tried that, but why would you do that……(other than to answer your question [emoji6])
send from my C6903
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Never tried that, but why would you do that……(other than to answer your question [emoji6])
I wouldn’t. I was asking because I don’t think it’s actually physically possible to pickle one prior to alignment which would mean it wasn’t the reason the OP’s GBU-39s were inaccurate.
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Yes! This is essential. Drop with SMS on one and HSD in other and make sure CZ has been pressed and is not highlighted. Maybe take a screenshot at your moment of pickle and post it here?
Thanks! Cursor zero was the issue. I love this weapon!!!
I don’t remember it being explicit in tutorials or manual.
Sent from my iPhone using Tapatalk
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I wouldn’t. I was asking because I don’t think it’s actually physically possible to pickle one prior to alignment which would mean it wasn’t the reason the OP’s GBU-39s were inaccurate.
Yeah, I guessed that [emoji106] [emoji106] [emoji106]
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Thanks! Cursor zero was the issue. I love this weapon!!!
If possible, I wait until I confirmed the target using the TGP before pickling, also great to double-check the CZ[emoji2]
send from my C6903
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Thanks! Cursor zero was the issue. I love this weapon!!!
I don’t remember it being explicit in tutorials or manual.
Sent from my iPhone using Tapatalk
Glad to help! CZing is important when dropping on preplanned coordinates with all weapons.
