Thanks, Garry. I suspected it would be something to do with the seeker angle relative to the missile, or the target angle relative to the seeker. Either/Or.
Though, for future reference, don't feel the need to define something from the ground-up; not with me at least, unless I mention otherwise. Might save you some time, and me some reading. For instance, paragraphs 6-9 are all I was after. The rest I either already knew, or could have reasoned out.
I don't think you are an idiot but it makes no sense explaining some bits and not others when I really didn't know what you knew and what you didn't.
I didn't just explain it for you either... I am sure there are plenty of people who didn't really think about and work out how they worked or perhaps made some false assumptions...
We've established how an IR missile is able to fly a pseudo-predictive route, and we know the same for a Radar guided missile (both SARH and ARH), but how do the two compare?
Well first of all there are old IR seeking missiles... newer ones.... and brand new state of the art ones.
For the very old missiles they just saw hot points and generally guided on the hottest thing they could see. Flares or the sun became decoys so the guidance logic often improved the design and logic of the seeker to go for the not so hot targets... which led to flares of different intensities released in groups.
UV filters were also used to tell the difference between the sun and flares which give off UV rays and aircraft surfaces which don't.
Finally new state of the art IR sensors use imaging seekers like thermal cameras that can actually see images and they pretty much become all weather day night TV guided missiles where you can select a part of the target to aim for...
The middle missiles were getting more sophisticated and after working out the direction of travel aimed slightly ahead of the hot point... meaning they hit the body of the aircraft instead of its tail pipe... making the warhead much more effective in destroying the aircraft.
Radar guided missiles generally have a larger warhead and a proximity fuse but generally go for the radar centre of the target... which is pretty much the best place to hit it, so aiming off is not really useful for them.
They use different inputs to determine their flight path, yet I wonder if one is more efficient than the other. The obvious go-to would be the radar guided, due to the information their guidance is based on.
Actually a disagree... radar is active and warns the enemy it is under attack... it also generates a signal that can be jammed or targeted itself.
It is perfectly possible to have rather small missiles... perhaps MANPADS size with a passive radar homing head... an ARM or anti radiation missile... that could be launched at the last second to shoot down in incoming AAM like Meteor or AMRAAM or R-77.
The new short range IIR guided missiles the Russians are supposed to be working on also have an anti missile function... as an AAM for fighters and bombers... as a short range defence missile for the Army and a CIWS missile for the navy... using datalinks to attack targets in a lock on after launch mode all completely passively.
Yet, the professional consensus over the last half century has been that radar missile seekers are appallingly reliable, while IR seekers are perceived as somewhat more consistent. One could assume, however, that this was directly related to the fact that one is an active seeker and the other passive; and so in one case, the would-be target has the option to manoeuvre, and in the other, they would not(most of the time).
This opinion is dirtied by the fact that IR guided weapons are generally short ranged and the most effective ones are generally fired from fairly close range from behind the target, while radar guided missiles are generally fired from greater ranges and their guidance alerts the target it is under attack.
Missiles move very quickly but have very small control surfaces so their ability to manouver is not that good... older missiles don't have good fields of view so once it blows past a target it wont swing around and reacquire them like in bad american movies.
It is the old story... you will most likely be killed in war by the bullet you never see coming...
Long story short:
Of Radar and IR seeking missiles, which would respond better to a manoeuvring target such as a jet? Would it be range specific? Would it be a negligible difference?
With modern IIR guidance you could use datalinks and lock on after launch for both missile types... the IIR missile would be passive but both would have an IR signature that would alert the target to the threat... except against third world countries.
Nothing is guaranteed a kill.
A mix of as many types would offer a pilot the best range of options for a kill.
For this it would be interesting to dig up info on missile statistics and whatever public domain info there is floating about.
The problem is that there is next to no information on the performance of Soviet and Russian T model missiles in real combat.
Export model Soviet fighters that had IR guided missiles were exported with Sidewinder based missiles... ie the MiG-23s had R-3S rather than R-23R and R-23T missiles let alone R-24R and R-24T.
The MiG-31 continues to use R-40TD missiles and for targets like the SR-71 in a head on interception they should be ideal... fast missile... big warhead... easy straight flying target...
The general consensus AFAIK is that the R-60MK is a good missile but not as good as late model Sidewinders... more a self defence missile.
The R-73 is better than late model Sidewinders in terms of range and manouver performance and seeker sensitivity.
Only the very late model AIM-9X with its IIR array seeker has a better sensor, but it really needs a helmet mounted site to make use of it high offboresight capabilities... something left off the F-22s to save money.
The R-73... even the first models had better flight performance.