F-5E GBU-12s on Nevada rarely tracking laser

I've been flying the F-5E lately, practicing dropping GBU-12s using AI JTAC vehicles (HMMWV TOW). On Caucasus, the GBU-12s have been tracking the laser ok, guiding to target vehicles without issues. However, on the Nevada map, it seems that most of the time the GBU-12s have been going dumb immediately after release and not hitting anywhere near the target vehicles. Seems that maybe 1 in 20 drops have the GBU-12 tracking the laser and guiding to the target vehicle(s).

Is there anything different in the process of dropping GBU-12s using an AI JTAC in Nevada than in the Caucasus map? I've done the same thing in both, calling up the JTAC vehicle, getting the tasking, 9-line, IP-Inbound, Laser On, SPOT, IN, getting Cleared hot... having prevoiusly turned on the external stores to BOMB, bombs arm to NOSE & TAIL, selecting the proper pylon, ensuring the select jettison is off. I generally drop from ~20k feet (the practice mission has manpads/IR SAMs), with a slight dive towards the target, 250-300 IAS.

As mentioned, in the Caucasus map mission, the bomb tracks right after release, but in Nevada it rarely does. Before diving in and making a simple Nevada mission so I can try and create a small track and post in the bugs forum, I'm just wondering if anyone else is having issues getting the GBU-12s to track an AI JTAC provided laser in the F-5E in Nevada.

EDIT - I'm using the default laser code of 1688 (checked the kneeboard), and that is the code the JTAC is mentioning in the 9-line, so I know the laser code is correct.

Thanks...

Maybe check your dive parameters, because average terrain in Nevada is significantly higher above MSL than in Caucaus, so if you start your attack run at the same height above MSL, then you have to adjust your drop point in distance.

Hmm, I've been dropping at ~20k feet, so even with the altitude of Las Vegas (near where I'm dropping), the ASL would be ~18k feet. I don't know if that would have much of an effect - also I've dropped from even higher (~22k feet) with the same result. Based on the F-5E manual, the parameters for 20k feet are as follows:

≈Dmin nm/km: 4/7 ≈Dmax nm/km: 6,5/12 IAS: 300

So maybe I'm too close to the target. Still, seems odd as I'm doing the same sort of approach in Caucasus, and I've certainly dropped from lower than 20,000, and the GBU has rarely dropped dumb.

Have you tried dropping GBU-12's in Nevada with the F-5E? Have you had this problem at all? Anyone? I've also tried with the F/A-18C and M-2000C and the GBU's have tracked OK with similar drop altitudes and distances as what I was doing with the F-5E.

In any case, I'll go higher (in Nevada) with the F-5E and see how it goes.

Thanks.

OK, back to report that the problem was apparently the F-5E driver :).

I ended up dropping from a little farther out, a little higher, and level with speed closer to the 300IAS recommended, and was more successful. I think the GBU seeker just likes to start out more level and farther away than I was dropping - when it then started to nose over, it appeared to pick up the laser more consistently and start gyrating to correct.

So, all is good apparently :).

Thanks...

I'm glad you got it working and thanks for letting us know what the issue was. That might help others as well :thumbup: