Rear-aspect IR missiles (AIM-9G) able to track Harrier from above wing

In the Harrier AV-8C I had a AIM-9G track and strike the aircraft from directly above while vectoring was set to 40%. The wings should of completely shadowed the jet pipes, especially when they were pointed downwards and away from the missile.

Is there something I’m missing here? Is there a realistic way it should of been able to track me, or does War Thunder not accurately simulate planes with sheltered jet pipes?

I’ve included a capture of the launch and moment of impact, which don’t seem like they should satisfy Rear-Aspect even for a normal jet?

This is not modeled in warthunder.

Heat signatures are purely related to the aspect of the aircraft to the missile, and the indicated engine temeprature.

So it’s not accurate but also not something that we can reasonably expect them to fix, it seems?

Take an IR picture of your car after you’ve driven it, with the hood closed.

Yes, and that is the concept behind all-aspect IR missiles, but the 9G is a rear-aspect which means it needs a much stronger IR signature than that which leaks through the skin of the aircraft and isn’t carried away by 300 knot windstreams.

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IRL the 9D/G/H had a pseudo all-aspect capability, as the significantly increased sensitivity of the gas-cooled seeker (relative to the earlier 9B and contemporary USAF 9E/J/N/P) meant the missile was easily capable of acquiring an afterburning target in a front-aspect engagement.

The only real limitation there was with the 9D, which required a deviated pursuit computer to tell the pilot when to fire - as the pilot couldn’t lead the missile itself while maintaining lock, due to the caged seeker - which was corrected with the SEAM system on the 9G.

That capability is why the solid-state 9H was chosen for further development into a true all-aspect weapon, which became the 9L.


As if only jet exhausts are actually hot… you think IR only works at temperatures of 700 degrees C and over?

It misses some angle to “unlock” it from you.

But also, the missile would have continued on the same course → interception course.

→ missile could have lost lock
→ you didn’t changed course
→ missile was close
→ missile was pointing on last known interception point
→ you entered the Missile Proxi-Fuze range
→ missile blow up
→ you’ve been shot by the missile

It’s not because a missile loose lock that Proxi-fuze don’t work.

IIR is a compeltely different to the older PBS detectors.
These detectors have an output where background radiation is indistinguisable from an aircrafts body.
If you are looking against a clear sky, it will pick up at close range, but against the earth or clouds it would not be able to distinguish the background from the target.

The heat of the engine, or side aspect view of the exhaust is required to pick up the target.
If the exhaust is covered, then the missile would only detect the heat signature of the aircraft at veyr close ranges.

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They need to overhaul engine temps and stuff. Not being able to “VIFF” and change a rear aspect shot into a side aspect shot drives me nuts. Not too mention the fact that harriers are hotter than an F-5C on full reheat

True. It’s almost impossible to lock F-5Cs from 1km+ distances. Meanwhile I can lock a harrier from 2-3km away in side aspect.

Yes, so? It’s a very clear side aspect shot and missile is very close range… he’s trust vectoring so he’s likely not very fast either. No reason that missile should have missed him… it’s in a direct intercept course, even if it would have lost track due to the aircraft position at that point, that missile is like a few 10s of meters away at full speed, it’s a done deal.

I use thrust vectoring in all high AOA maneuvers regardless of IAS as per AV-8A/C flight manual, not just at low speeds. The IAS was around 340 knots at impact.

The issue is not whether the missile should of been able to hit in the final shot, at that point it was obviously a done deal, the point was that early rear-aspect only missiles need a clear view of radiating (aka very hot) solid surfaces. For most jets, this means the exhaust ducting and surrounding cowling, plus unburnt super-heated carbon during after-burning (aka what you can actually see glowing - clean air does not radiate).

In the case of the harrier, this means the rear jet pipes, which duct low bypass jet exhaust. The front pipes are fed from the turbofan without any hot exhaust, and are relatively cool.

Now, the earlier complaint about rear-aspect missiles easily locking onto Harriers from side-aspect is actually realistic - side on provides the clearest view of the hot rear jet pipe. The problem I have is top-down should be nearly impossible for early rear-aspect missiles to acquire and track.

tl;dr - the Harrier should be easily acquirable from side-aspect but nearly impossible from top-aspect.

Regarding the other IR image of a harrier in hover, early (pre-late 90s) thermal cameras could not have picked up IR emissions from the relatively low hot exhaust carbon content, and this is not proof that one designed in the 50s should of. Remember, air does not radiate IR, only solid particulates suspended in the air does. If air radiated any IR camera would look like it was permanently in glowing fog as the air between it and the target got in the way.

Also, it is worth noting that the Harrier is not the only jet with top-down shadowing of the jet pipe, others like the F3H-2 should also be significantly harder to lock top-down when not using afterburners.