F-4J radar will lose lock on enemies and prioritize friendlies. Sparrows will still hit the switched target many seconds after turning radar off

I’ve went into a match and enslaved an aim9g to a mig29, the missile eventually killed an f-4s on my team. I’ve then proceeded to lock on a tornado with an aim7f and the tornado flew like 1km away from a mig23 ML. The ML wasn’t even going sideways but somehow the radar on doppler mode swiched from the tornado that was going towards me onto the mig23 ML. As soon as I saw it, I cancelled the lock and went back to the tornado. When I saw the missile was still going for the Mig23 ML i switched off the radar. Ten seconds later after turning radar off the missile hit the mig23 ML. I want this to be fixed. I don’t want to get any ban for unwanted teamkills.

if you’re using PDV it does not have identify friend or foe, it’ll priotize the target with the biggest radar signature, and with the 9g that’s an IR missile all that radar locking does is make it easier to get a lock it doesn’t guide the missile, and its risky to fire an IR missile if there’s a teammate Infront of you

i wasnt using pd, i was on src and the target was 11km away, well above the ground clutter.

When firing IR guided missiles using radar slaving, the seeker is only slaved prelaunch, once the missile has been fired it is completely under its own guidance, so if a hotter target crosses its FOV it will switch targets.

Now regarding the Sparrows, the locked target isn’t necessarily the target the missile will guide on to. Your aircrafts CW illuminator isn’t like a laser, its more like a torch with a wide FOV, this can lead to situations where your missile will target the strongest return in the CW illumination cone rather than the “locked” target.

Somewhat like this;

Sparrows also coast on their last course when lock is broken for around 4~ seconds, so if the friendly stayed on course the missile will still hit.


It’s not quite right as implemented as there should be an additional set of filters to prevent that behavior. Targets swapping mid flight shouldn’t really occur at all as the tolerances are much tighter, and Conical scanning means that the duty cycle of a 2nd target is much less then the tracked target.

at speedgate lock on to the missile’s seeker looks to where it thinks the locked target should be based on the precomputed English bias command and attempts to lock its speedgate onto the return echo from the illuminator, and from there it uses a much narrower tracking gate to filter out clutter and track the apparent closure rate between the missile and target.

It should also require that the closure rates be similar enough to be within the speedgate at before lock on occurs as well to swap tracks (it’s a ~85% the range assuming the 2nd target has the same RCS and is sitting at the HPBW angle 7 degrees for the FM-CW guided AIM-7s)


Indeed, and there is reports in for that for the Skyflash series of missiles. I can’t see one for all Sparrows though. But I was referring to its in game behaviour.

The lack of English Bias commands is also reported.

Should add if you want to turn this into a report @tripod2008 go for it and I’ll forward it on.

From memory there might have been an overlapping report previously, I think it may have been reported by @nighthawk2174, I’ll look back though the AIM-7 thread on the old forums to check.

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Cheers, if you find one let me know I’ll give it a nudge.

Also is the report in question this one?

That’s the Skyflash one yes, not directly about the issue you described but can only be fixed in the same way.

I was I found the report I was thinking about see link below, but it’s not exactly coving the issue in its entirety.

So it’s sort of partially been reported already but this new report would build on that, would it be much of an issue if I paraphrase certain sections.

Can’t see an issue with that.