This lock is different from a BVR lock using a radar. This is not even a lock, it is merely tracking using heat signatures.
A heat seeker missile fired from close distances targeting a J-20/F-22/PAKFA has higher chances than an active seeker fired from BVR distances of 18Km and greater.
Using IRST, all we know is there is an object in the sky producing a lot of heat, no other information is given. If you look at the aircraft from the front, the heat could be around 150[SUP]o[/SUP]C, from the back it could be 200-300[SUP]o[/SUP]C, with After Burners it could be 1200-1500[SUP]o[/SUP]C. So, WVR missiles use the engine heat energy to produce a lock. Note that this lock can be broken through other ways like using flares, maneuvering, using cloud cover or the simple and effective out running the missile.
During dog fights, aircraft use a combination of high energy turns, vertical climbs etc to out maneuver the enemy. This is done by using a combination of potential energy and After Burners. To maintain this high energy ABs are used quite frequently and this is what missiles use to "lock on."
On 5th gen aircraft, say the F-22. The heat radiated by engines is significantly lesser than on 4th gen aircraft.
tHIS IS what your LM guys want us to believe it is impossible to hide heat. you can spreaad it.But cant hide it.
Flat nozzles help dissipate heat energy quicker than round nozzles. Ceramic tiles are used to cover the walls of the engine and engine nozzles.
I am talking about the jet stream that blows out of the nozzle.
This further reduces heat. Apart from this, unlike 4th generation aircraft, F-22 does not need to use After Burners to maintain high energy states. This is because of the F-22s ability to supercruise. Using regular cruise modes, the F-22 can manage a speed of Mach 1.7 without having to use ABs. This reduces heat radiated by 3 to 4 times compared to a normal 4th gen fighter. Since ABs are not used, the heat energy is lesser and a small seeker will not be able to pin point the heat source from chaff which burns at higher than AB temperatures of 3000[SUP]o[/SUP]C. So, if the F-22 is moving at Mach 1.5 and releases high temperatures chaff, the seeker will not follow the very low temperature F-22 exhaust plume and will lose to the F-22's readings due to the excess speed.
Even from far ranges, while the F-22 is cruising at Mach 1.7, the IRST will not be able to pick it up at least upto 30-40Km. This is a figure the Russians claim.
So, considering the above, what will you do if you detect the F-22 even from 30Km away? Forget detection, first you will need to train the 4th gen pilot to identify the heat signature of the F-22 from another aircraft. OLS cannot identify aircraft from long distances, the identification happens at very small distances. The F-22 is like a small dot on the screen. So, all you know is there is something there, it can be a F-22 or some satellite debris falling from space. It could be a hot air balloon or it could be a ball of plasma. However, at this range the F-22 would have already killed you because it can still see you from 400Km away while you are struggling to identify the strange heat anomaly from 30Km away(well within the kill range of Aim-120D).
When it comes to heat seeking missiles, it is primarily used in WVR combat. Here 5th generation aircraft completely take away all advantages of WVR missiles, except for speed. When a rocket powered missile is launched, it is the fastest in the initial stage, after which it slows down due to air resistance. So, if you want to maintain speed, then you will have to fire the missile at close ranges of 500m to 10Km. Beyond which most WVR missiles have nearly run out of fuel. A shot like this can kill a 5th generation aircraft.
But there is a problem here!!! Do you know what the problem is? The problem is the F-22 pilot should be stupid enough to get into a dog fight in the first place. Even before that, you should know there is a F-22 flying around for you to engage and therein starts the difference between a 4th gen aircraft and a 5th gen aircraft.
The difference between stealth and non stealth is Too Much. It is not like the difference between F-4 and F-15 which are third and fourth generation fighters. When F-15 replaced the F-4, it was designed to have a kill ratio of 7:1 against the F-4. A Mig-21 with a good radar and a BVR can still kill a F-15, even though it has only 2 shots. A F-4 too has good chances in a one on one fight against a F-15. But the difference between a F-15 and a F-22 is like heaven and earth. The kill ratio was found to be 104:0. As in 104 F-15s lost to F-22 and not one single F-22 was lost. Simply too big a gap to bridge with avionics and AWACS alone. You can send 6 F-15s against the F-22 and still not score a single kill, while the F-22 could have killed all of them and gone home even without coming close.
