hmm I play sim games quite a bit and wonder about some things in reality , when an IR guided missile is locked
on to you how would the pilot/computer in the victim plane know a lock is on him since IR is a passive medium of detection , I mean its understandable for radar guided , semi active radar guided (even radio command since the radar on the firing platform is illuminating the target on the radar)
also would incomming laser guided missiles such as the
AT-16 Vikhr show up on missile approach warning systems
since it follows a dot of light on the target surely onboard
systems can’t detect that can they?
or is it something i suspect like the onboard computer calculates tragectories of incomming objects and intercept courses and then computes if that missile has its name on it? …
hm just something thats been bothering me for a bit any takers?
One possibility might be that passive IR missiles are still very much in contact with the plane that fired it, sending back radiotelemetry and the like.
A missile warning system might be able to discern that a) there is a missile in the air; b) that it has locked on to a target when the radiotelemetry begins sending different or more frequent signals; and c) that it is closing in on the target, either through use of RDF or signal strength.
I beleive it isn’t the IR that the target detects, but rather the attacker’s ranging radar that tells him or her if they’re within range and other paramaters to launch the IR missile in the first place. The same would apply for a laser-guided air-to-air missile, unless the attacker had some system that allowed them to get the range and aim by laser alone.
I heard a Soviet claim for such for the MiG-29 when it first came out; that they could laser range and aim the gun armament very accurately without having the main radar on. Sounds suspicious to me.
When “aquiring” a target for an IR missile, the aircraft sends a signal to the missile to start looking for a target. The aircraft manuevers to place the target into a narrow cone in front of the missile, using, in many cases, radar to aid in the keeping the target in the aquizition zone, until the missile signals back that it has locked onto, and is tracking, a valid target (valid targets must be in the aquizition cone and have the properties the missile is looking for: Correct wavelength of IR, multiple frequencies, or whatever the designers have specified).
At this point, the pilot launches the missile and hopes for a hit. Once the IR missile is away, no further communication between missile and launching aircraft take place (hence “passive”). The target will likely have recievers that note the change in the hunter’s radar mode from “scan” to “track”, which will set off warning alarms. That’s all the warning, if any, that many aircraft get before the arrival of the missile. If the target is warned of a launch, he will attempt to manuever, decoy, or (most likely) both, to escape the missile. Seeker heads on missiles have a fairly restricted range of motion, so if the target can get outside the cone where the missile can see it, it can usually escape. Alternativly, if the missile sees something more attractive (like a decoy flare), it may track that instead of the target.
If the hunter can sneak up on a target, he may be able to set-up a shot without using radar to track the target, and so get an unannounced shot, where the target’s first warning is the eject alarm.