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I don't know - with increasing missile speed the target reaction time, and the required lead angle against a manoeuvring target both drop significantly. (In the limit you have a laser with (practically) no lead requirement and instantaneous TOF)
The combination of a roughly 6:1 missile-target velocity, and a huge warhead with SARH is probably lethal against a fighter at around Mach 1 that doesn't succeed in leaving the engagement envelope (by terrain masking, or for thermal considerations etc).
To intercept a crossing target with a 6:1 speed ratio, you need about 9.4 degrees of lead. A fighter turning through 90 degrees at 1000km/h and 7G takes just over 6 seconds to complete the turn, in the same time, the missile must correct it's course by 9.4 degrees only, and this only requires 4.4G to complete the turn in the same time. While I don't know what the overload capability of the missile is, I would be very surprised if it was as low as that (or even near to it). At longer ranges and lower speed ratios, the lead angle and turn rate must be higher, and 'G' required remains fairly similar - eventually the maximum cN of the missile will be reached and it won't be able to sustain the rate... continuous fighter manoeuvring might increase the missile TOF and reduce speed somewhat, but the energy of the S200 is so high, and closure so rapid that it might have less effect than you might expect. Probably the 'best' bet is either a steep dive, away from the radar (hoping for overheating of the missile, reduced closure and eventual loss of illumination due to terrain masking) or a moderate dive heading obliquely towards the missile track (slightly forward of the 3/9 line) at maximum linear acceleration hoping to increase the lead requirement to a maximum and also to draw the missile down into thicker air where drag & heating are high, and fighter manoeuvrability is maximised for a max-g-break across the missile's path.
The big warhead is intended to ensure destruction of large nuclear armed bombers, but it will also reduce absolute accuracy and precision requirements in the terminal phase guidance on a manoeuvring target - the allowable miss distance for a probable kill is limited only by the fusing sensitivity and target RCS (and armed conventional fighters tend to be 'big' radar targets compared to their physical size due to pylons, weapons, engine installations, and airframe shape).
Whether it is economic to expend multiple missiles against an aircraft other than an SR71, a strategic bomber, or a strike aircraft aimed at the 'protected' target is another matter... There may well be far more 'fighters' available than you can realistically engage, and firing the limited missile supply against CAP/Escorts will not allow future or immediate engagement of the strike package.
Last edited by Lieste; 05/25/12 06:08 PM.
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I don't know - with increasing missile speed the target reaction time, and the required lead angle against a manoeuvring target both drop significantly. (In the limit you have a laser with (practically) no lead requirement and instantaneous TOF)
The combination of a roughly 6:1 missile-target velocity, and a huge warhead with SARH is probably lethal against a fighter at around Mach 1 that doesn't succeed in leaving the engagement envelope (by terrain masking, or for thermal considerations etc).
To intercept a crossing target with a 6:1 speed ratio, you need about 9.4 degrees of lead. A fighter turning through 90 degrees at 1000km/h and 7G takes just over 6 seconds to complete the turn, in the same time, the missile must correct it's course by 9.4 degrees only, and this only requires 4.4G to complete the turn in the same time. While I don't know what the overload capability of the missile is, I would be very surprised if it was as low as that (or even near to it). At longer ranges and lower speed ratios, the lead angle and turn rate must be higher, and 'G' required remains fairly similar - eventually the maximum cN of the missile will be reached and it won't be able to sustain the rate... continuous fighter manoeuvring might increase the missile TOF and reduce speed somewhat, but the energy of the S200 is so high, and closure so rapid that it might have less effect than you might expect. Probably the 'best' bet is either a steep dive, away from the radar (hoping for overheating of the missile, reduced closure and eventual loss of illumination due to terrain masking) or a moderate dive heading obliquely towards the missile track (slightly forward of the 3/9 line) at maximum linear acceleration hoping to increase the lead requirement to a maximum and also to draw the missile down into thicker air where drag & heating are high, and fighter manoeuvrability is maximised for a max-g-break across the missile's path.
The big warhead is intended to ensure destruction of large nuclear armed bombers, but it will also reduce absolute accuracy and precision requirements in the terminal phase guidance on a manoeuvring target - the allowable miss distance for a probable kill is limited only by the fusing sensitivity and target RCS (and armed conventional fighters tend to be 'big' radar targets compared to their physical size due to pylons, weapons, engine installations, and airframe shape).
Whether it is economic to expend multiple missiles against an aircraft other than an SR71, a strategic bomber, or a strike aircraft aimed at the 'protected' target is another matter... There may well be far more 'fighters' available than you can realistically engage, and firing the limited missile supply against CAP/Escorts will not allow future or immediate engagement of the strike package. V880E overload capability is simulated as depending of its flight altitude. H=0m - 10g H=20km - 6g H=40km - 1g NATO AWACS planes had to regularly practice emergency sinking to low altitude, during the Cold War, to evade the Gammon... 
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this one only for mr.hploook at this video! one american f-16 run from 6 sa-2 missiles over iraq! how did that?? sa-2 can keep 7 until 9 g focres!!!! that f-16 do it only with hard manuever for run! no jaming keep loook at this http://www.aparat.com/v/9c78a1ce36cf29e1e9c2fc5ee3641f74191329
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A missile typically need about 5x the g's that the aircraft is pulling in order to hit that aircraft. So, if the SAM can only maintain 9g, you can escape it with a 3g maneuver (sort of. You probably need to maneuver harder in a bunch of cases)
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and fighter manoeuvrability is maximised for a max-g-break across the missile's path. Orthogonal roll - out of plane maneuver betters your chances for ditching the missile, less energy used, keeps you out-of-plane for the follow-up shot as well.. The missile will sail past, and potentially not detonate the warhead in the best of circumstances - you might escape most or all of the shrapnel.
Last edited by GrayGhost; 05/25/12 07:29 PM.
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Only valid for extremely close ranges associated with light AAM, and beam-riding or pure-pursuit missiles.
The removal of the requirement for a direct hit greatly reduces the terminal manoeuvring required (though a close miss is still far better than a very wide one). A high ratio of missile to target speed eliminates much of the ability to change lead angle (and thus force the missile to manoeuvre.
As 1g is level flight, your example should be 10g missile > 4g manoeuvre in any case, but I still think that it is invalid for most cases of modern missile guidance and larger missiles.
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A missile typically need about 5x the g's that the aircraft is pulling in order to hit that aircraft. So, if the SAM can only maintain 9g, you can escape it with a 3g maneuver (sort of. You probably need to maneuver harder in a bunch of cases) are u series??? i dont think so lik u u said need about 5x aircraft g! also it ever cant be a deram!!! until in reality wourld!... because one f-16 can manuever around 8 gs! the missile have to keep 5x * 8 = 40 gs  It really is incredible i think we have new sobject about g force missile for hunting with sa-2!  mr.hp wee need your help to finde solution for this post!!! come over here please 
Last edited by milang; 05/25/12 07:46 PM.
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Only valid for extremely close ranges associated with light AAM, and beam-riding or pure-pursuit missiles. Valid for any missile, including homing types. The removal of the requirement for a direct hit greatly reduces the terminal manoeuvring required (though a close miss is still far better than a very wide one). A high ratio of missile to target speed eliminates much of the ability to change lead angle (and thus force the missile to manoeuvre. Actually no, it doesn't, and real life supports this. You employ out-of-plane maneuvering and things start working out. The fuze might not work reliably, or may detonate in less-than-optimal geometry and not cause enough damage to kill the target (possibly it may not even mission-kill). As 1g is level flight, your example should be 10g missile > 4g manoeuvre in any case, but I still think that it is invalid for most cases of modern missile guidance and larger missiles. Depends on when the missile was designed and what it targets. R-27's are limited to about 35-40gs. Sidewinders as well. R-73's to 45. Newer missiles are capable of 50-60g's. This all depends on missile speed at intercept though - if it goes too fast or too slow, you won't get peak performance. Most modern PN using missiles tend to use a PN multiplier of about 5, and this is where this rule of thumb comes from: To intercept a target you need 5 times its acceleration.
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A missile typically need about 5x the g's that the aircraft is pulling in order to hit that aircraft. So, if the SAM can only maintain 9g, you can escape it with a 3g maneuver (sort of. You probably need to maneuver harder in a bunch of cases) are u series??? i dont think so lik u u said need about 5x aircraft g! also it ever cant be a deram!!! until in reality wourld!... because one f-16 can manuever around 8 gs! the missile have to keep 5x * 8 = 40 gs It really is incredible Correct. AIM-9L/M structural limit is 40g, and it can turn hard enough to exceed 40g in a very limited set of cases. 
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so with this logical reasons... i think work with sa-2 sa-4 and sa-5 is realy Waste of time!  of course i stiil love with sa-3 
Last edited by milang; 05/25/12 09:08 PM.
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Riight... sure - the peak 'g' capability is just what you need to compare at extended range (where manoeuvring can work)...
You will not outmanoeuvre the AIM9 when it is capable of 36-40g, only once the overload capability has fallen to less than or equal to the aircraft (in the case of an optimal out-of-plane manouevre), or around 70% in a transition from zero to maximum crossing angle.
This is 13.2km for non-manoeuvring fly-out (from mach 0.9 and 20kft, with a 7G capable target), and some proportion of that for the energy depleting manoeuvring-all-the-way cases*. Around 5km the missile cannot be out-turned, the motor is only just burning out, so all-the-way turning is not a huge problem and the only safety is in decoys and signature reduction.
The AIM9 also has a rather inefficient lead-pursuit curve, as it has no knowledge of target range to go. With this information a minimum energy profile can be flown with mid-course update if absolutely required, and then the pursuit is flown only in the terminal phase. (*As the missile in question performs continuous turns because of the guidance laws I'm not sure how much additional energy you will burn by forcing a sustained turn in one direction, compared to s-turns)
Larger missiles don't manoeuvre as well, but they are typically faster and denser so require less manoeuvring and lose less specific energy per km and for the required turns. With optimised flight profiles they can also minimise time of flight and/or energy used to reach the target.
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The peak g capability is just what you need to compare it against its optimal range, and the rest of it is just as useful for when you're outside that range. That's how you figure out what sort of maneuver you will execute depending on your distance from the bandit. You can outmaneuver an AIM-9 when it is capable of 36-40g. But if we're assuming that the bandit launched in good parameters, that would be a bit of a 'fat chance'. In any case, airframe capability alone is not the end of maneuverability issues for a missile. Riight... sure - the peak 'g' capability is just what you need to compare at extended range (where manoeuvring can work)...
You will not outmanoeuvre the AIM9 when it is capable of 36-40g, only once the overload capability has fallen to less than or equal to the aircraft (in the case of an optimal out-of-plane manouevre), or around 70% in a transition from zero to maximum crossing angle. Actually at 13 km you'll hit bupkus with an AIM-9 against a maneuvering target. It's rather likely that your seeker won't even lock-on at that range, never-mind the kinematics, which wouldn't cooperate either. The AIM-9 is a short-range missile. At 5km you can out-maneuver it if you've set yourself up to do so. If you haven't, good luck with that. Setup is everything. This is 13.2km for non-manoeuvring fly-out (from mach 0.9 and 20kft, with a 7G capable target), and some proportion of that for the energy depleting manoeuvring-all-the-way cases*. Around 5km the missile cannot be out-turned, the motor is only just burning out, so all-the-way turning is not a huge problem and the only safety is in decoys and signature reduction. The AIM-9 flies a pretty efficient PN collision given what it is meant to do. It is a dogfighting missiles, meant to be used at short ranges. I don't know why this is even being brought up, since just about any missile with terminal homing will employ PN for terminal intercept. The AIM9 also has a rather inefficient lead-pursuit curve, as it has no knowledge of target range to go. With this information a minimum energy profile can be flown with mid-course update if absolutely required, and then the pursuit is flown only in the terminal phase. (*As the missile in question performs continuous turns because of the guidance laws I'm not sure how much additional energy you will burn by forcing a sustained turn in one direction, compared to s-turns) Actually they will lose a lot of energy, especially if they need to turn. This is why they have monstrous rocket engines. Again, I'm not sure why this is being brought up. This has nothing to do with the escape maneuver at the terminal stage of the engagement, other than to dictate the energy level of the missile ... which we can do without considering any of this. Missile has x g available, you can out-maneuver it if you pull a y g escape maneuver. Larger missiles don't manoeuvre as well, but they are typically faster and denser so require less manoeuvring and lose less specific energy per km and for the required turns. With optimised flight profiles they can also minimise time of flight and/or energy used to reach the target.
Last edited by GrayGhost; 05/25/12 10:14 PM.
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A missile typically need about 5x the g's that the aircraft is pulling in order to hit that aircraft. So, if the SAM can only maintain 9g, you can escape it with a 3g maneuver (sort of. You probably need to maneuver harder in a bunch of cases) Ahhh, the old rule from the Vietnam war pops up again... ... it was calculated 3x, as the V-750 (Guideline) missile was flying around Mach3, while the target was doing something around Mach1. If the plane and the missile travels at the same speed towards each other ahead, they need to pull the same g for a direct hit. If the missile does double speed, it needs double g's to achieve direct hit. etc... Now I digged out... Hmissile=0..20km it is able to pull 10..6g Hmissile=20..35km it is able to pull 6..2,5g They calculated, that with the proportional guidance method, the V-880 flying, it is capable to hit targets flying at: Htgt= 1..5km pulling 5..7g (fighters of the 70') Htgt= 10..11km pulling 3..5g (AWACS, standoff jammers) Htgt= 20km pulling 1,5..2,5g (HABU)
Last edited by Hpasp; 05/26/12 07:07 AM.
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I still disagree that the required g goes up with increased speed (as the lead angle required falls at ~ the same rate as turn rate decreases, so turn time to alter lead remains nearly constant). If anything the 'g' requirement may increase as missile speed reduces, but only very slightly.
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Ahhh, the old rule from the Vietnam war pops up again...
... it was calculated 3x, as the V-750 (Guideline) missile was flying around Mach3, while the target was doing something around Mach1. It is still a valid rule, and it comes from the PN constant. If the plane and the missile travels at the same speed towards each other ahead, they need to pull the same g for a direct hit.
If the missile does double speed, it needs double g's to achieve direct hit.
etc... Same g's are not enough at the same speed unless evasion is done in-plane. However, you are right (even if you did not say it, I know you meant it) about one thing that affects all things in aviation: The real answer tends to be 'It Depends'  They calculated, that with the proportional guidance method, the V-880 flying, it is capable to hit targets flying at:
Htgt= 1..5km pulling 5..7g (fighters of the 70')
Htgt= 10..11km pulling 3..5g (AWACS, standoff jammers)
Htgt= 20km pulling 1,5..2,5g (HABU) Must have been pretty slow fighters, without out-of-plane maneuvers. I don't think an AWACS could pull 5g if it's life depended on it.
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It is only valid for low aspect, low manoeuvring cases. It vastly overpredicts the required 'g' for crossing targets, and for rapid target manoeuvres. See: Quasilinear PN equations paper. In particular diagrams 2b and 2c, where required 'g' is approximately 1.5 target 'g' at zero relative range and a 3:1 relative velocity. As missile speed, or Target 'g' increases the relative 'g' required falls, as does required 'g' when target aspect is high. (When aspect is 90 degrees and the manoeuvre is out of plane, to change the lead angle by 26 degrees (18.4 degrees lateral lead to 18.4 degrees vertical lead), the target must change direction by 90 degrees... almost 4x as much) Remember, that these missile are still on thrust programs at lower altitudes, reducing any loss of 'flight performance' with manoeuvring (Thrust >> Drag for the boost phase and > Drag during the sustain, and normal missile behaviour admits low rates of turn to stay 'straight' - biasing the recovery of rate in one direction permits a gentle sustained turn with no appreciable increase in drag over the normal case). It is also not a requirement to actually strike the target, and at low relative range and high altitude, the very large warheads can damage targets up to 250m from the fusing location - lower down the guidance is better, but the fragments travel less far with lethal effect due to air resistance - even so a 100m miss could be lethal - this is 10x or more the typical light AAM. At high speeds, fighter turn radii are in 100s of meters to several km range, and high supersonic maybe 10s of km... While this allows manoeuvring to force the SAM to travel longer distances to reach the intercept point, this is a fairly leisurely 'rate of turn' and something that is only an issue to a missile running near the upper half of the range envelope - closer than this and energy isn't a huge problem, and neither is 'g' availability. At lower 'target' speeds the aircraft is far more agile, and this actually raises the missile 'g' requirement, increasing the probability of a miss... but reducing the miss distance for a lost track at the same range to go... Even if the missile cannot 'match' the turn requirement doesn't mean that a miss is assured - you will first have reduced lead, then drop into a lag pursuit - this will reduce turn rate requirement but reduce closure (as it does with aircraft), if the missile speed is high enough and range not too extreme then a fusing miss is still possible even though the missile 'cannot intercept'). I think that '3 g' refers to AWACS, and 'up to 5g' to EF111 or EA6B aircraft. Both lying in the 'AWACS and Standoff Jammers' group.
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today video !
persian tor-m1 upgraded from 12km engage range to 20km range!  dear grayghost i think tor can destroy fighter with hardly manuevering ! i love it http://www.aparat.com/v/bf0bfa62d86ae7dea657f78ff863461e162097
Last edited by milang; 05/26/12 05:52 PM.
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At high speeds, fighter turn radii are in 100s of meters to several km range, and high supersonic maybe 10s of km... This is generally true for sustained turns, not instantaneous turns. A fighter has no problem pulling heavy g's up to the AoA limit. It's just going to burn speed for turning. I think that '3 g' refers to AWACS, and 'up to 5g' to EF111 or EA6B aircraft. Both lying in the 'AWACS and Standoff Jammers' group. That would make more sense, yep ... the F-111 is a 5g airframe.
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Say hello to AESA-EW, SDBs and JDAMs capable of flying 20nms, JSOWs, TALDs, SLAM/ER's, and HARMS; that's high-altitude attacks only. Low altitude are also not a good deal for any SAM. SAMs have always been, and will always be a speed-bump. You won't stop an air force with SAMs alone (unless it's an air force that really, really sucks for whatever reason). Generally speaking though yes, the newer the missile, the harder it is to evade kinematically.
Last edited by GrayGhost; 05/26/12 05:58 PM.
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