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The AIM-9 Sidewinder missile - Information & Discussion topic


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On 24/04/2021 at 16:09, The_Monolith said:

L_M_Performance.JPG

I saw that someone posted this in your topic over on the DCS forums, supposedly showing the AIM-9L capable up to 40g. Did you ever figure out where it came from? I looked around for a bit and didn't find much. I did find this funding document with some info on several missile types, with this cool prototype making an appearance as well.

image.thumb.png.7266aeb628b1f49688796346

https://books.google.co.nz/books?id=149HAQAAMAAJ&pg=PA4582&lpg=PA4582&dq=AIM-9L&source=bl&ots=yo0VQdyluq&sig=ACfU3U39yFA2eyJkIul6SVpnZcae5pu_7Q&hl=en&sa=X&ved=2ahUKEwj6jLWW-5bwAhVNVisKHYPmDnYQ6AEwEXoECAgQAw#v=onepage&q&f=false

 

so far its the best source we have, and I think there is some validity to it

I think the actual value is somewhere in between 30 and 40g

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  • 2 weeks later...
1 hour ago, _Condottiero_ said:

These look like J or P, aren't they?

EivyoWyWsAAdqsX.png

They do indeed. 

 

Edit: The aircraft is a Turkish F-104G for anyone wondering

Edited by Flame2512
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  • 2 weeks later...

@Zetaris You seem to know a bit about this proportional navigation stuff. I noticed in the Lightning weapons system manual it says that when slaved to radar the Red Top used information from the radar to adjust it's guidance parameters:

Spoiler

M1INUmi.png

 

In this context k-factor is the proportional navigation constant and apparently a value between 3 and 8 is used. Do you have any idea if this behaviour typical of radar slaved / SEAM IR missiles or is it something only the Red Top does?

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11 hours ago, Flame2512 said:

In this context k-factor is the proportional navigation constant and apparently a value between 3 and 8 is used. Do you have any idea if this behaviour typical of radar slaved / SEAM IR missiles or is it something only the Red Top does?


Yes, I think K-factor is an alternate term used for PN multiplier. I can’t recall reading anything in the F-4 tac manuals suggesting AIM-9G/H does the same things, so it seems only the Red Top (and possibly the Firestreak, iirc) does this. Outside of IR missiles, I’m very sure the AIM-7E does similar things (using radar to provide information on k-factor, guidance values changing depending on altitude & aspect).

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Repost from AIM-7 thread since it's also relevant here:

 

So uh, I woke up this morning, decided to test some custom missile stuff, and holy ****, t rack rate now appears to be active on live server:

 

 

EDIT: Some quick testing shows that only very low track rates of less than ~10°/s will noticeably limit maneuverability. E.g. I found no noticeable difference between a custom AIM-9J with standard 16.5°/s or 100°/s -- the missile is limited purely by G limit and fin deflection.

 

Track rate also has no effect pre-launch, meaning the track rate pre-launch is still effectively unlimited.

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AIM-9Js flares immunity is at a unacceptable level, it definitely needs to be reduced before the patch drops 

Edited by WreckingAres283
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Agreed

It still has the older seeker but with 2.5 degree FOV, and that reduced FOV is the same as the AIM-9D and that thing is distracted by flared like a moth to a flame from any range.

 

Aim9J on the other hand is impossible to dodge unless you pull a very high G turn and dump **** loads of flares with no afterburner. That is more akin to the capabilities of the AIM-9M with actual IRCM filtering from the Insb detector, while the AIM-9J used the same PBS detector as all other early sidewinder variants.

Edited by Celestia
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On 26/05/2021 at 08:03, Celestia said:

Agreed

It still has the older seeker but with 2.5 degree FOV, and that reduced FOV is the same as the AIM-9D and that thing is distracted by flared like a moth to a flame from any range.

 

Aim9J on the other hand is impossible to dodge unless you pull a very high G turn and dump **** loads of flares with no afterburner. That is more akin to the capabilities of the AIM-9M with actual IRCM filtering from the Insb detector, while the AIM-9J used the same PBS detector as all other early sidewinder variants.

I saw lnsb filter was mainly for ranged all-aspect guidance.

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On 26/05/2021 at 01:03, Celestia said:

That is more akin to the capabilities of the AIM-9M with actual IRCM filtering from the Insb detector

thats not how IRCCM works

IRCCM is archived by using a Frequency modulating seeker, not a Amplitude modulation like all sidewinders had before AIM-9L

On top of the seeker the M uses smart software to filter out incorrect signals electronically.

 

the material of the sensor has nothing to with this.

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gg, F-4E fired 9J on me, I dumped all 12 flares of my 23, AB off, 80° out turn, the missile still hits me.....if they dont fix this, MiG-23M wont be playable (or any other jet thats facing it)...

this isnt funny and has nothing to do with realism or balance.....

 

meanwhile, any other top tier missile (maybe except 9P) is very vulnerable for flares (even Magics)

 

Edited by WreckingAres283
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21 minutes ago, WreckingAres283 said:

gg, F-4E fired 9J on me, I dumped all 12 flares of my 23, AB off, 80° out turn, the missile still hits me.....if they dont fix this, MiG-23M wont be playable (or any other jet thats facing it)...

this isnt funny and has nothing to do with realism or balance.....

 

meanwhile, any other top tier missile (maybe except 9P) is very vulnerable for flares (even Magics)

 

isnt the flare way bigger than the rest that should have helped you to avoid lol

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3 minutes ago, TimeFaker said:

isnt the flare way bigger than the rest that should have helped you to avoid lol

it should, the flares of the MiG-23 are huge….

 

but this problem doesnt stays on devserver, once a time i dumped maybe around 20 flares of my 21bis, AB off tho, turning (while dumping flares), the missle was launched from 3km and still hits me…..

i can tell u many more situations like this, and i can tell u, this missile is 100% messed up….meanwhile R-60 likes to follow flares like a moth flying to streetlight

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22 minutes ago, Einherjer1979 said:

 

 


Yes, Aim-9J immunity to flares is on ridiculous level now. 

At the same time R-60 is flying to flares like a moth to a flame even when Phantoms are still with afterburner turned on. It's plain stupid...I mean "balanced" to help "US suffer" teams. :facepalm:

 

eh, the 9J is ridicously immune to flares, and the R-60 has limited all-aspect capabilities. Both missiles overperform in certain aspect, the balance of power is preserved. Bear in mind I don't think it should remain that way, and I think both of those missiles should be nerfed in these aspects, however I certainly do not want a situation where only the US 9J is nerfed while the R-60 remains as it is

Edited by Absolutely_Free
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9 minutes ago, Absolutely_Free said:

eh, the 9J is ridicously immune to flares, and the R-60 has limited all-aspect capabilities. Both missiles overperform in certain aspect, the balance of power is preserved. Bear in mind I don't think it should remain that way, and I think both of those missiles should be nerfed in these aspects, however I certainly do not want a situation where only the US 9J is nerfed while the R-60 remains as it is

facts:dntknw: (upvote counter broken af)

 

btw, on devserver today, I didnt managed to get an all aspect lock with R-60s, so that seems to be fixed (?)

Edited by WreckingAres283
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12 minutes ago, Absolutely_Free said:

the R-60 has limited all-aspect capabilities

 

4 minutes ago, WreckingAres283 said:

btw, on devserver today, I didnt managed to get an all aspect lock with R-60s, so that seems to be fixed (?)

 

Also on live server R-60 has no "limited all-aspect capabilities" when we talk about clean headon.

It can hit afterburning target at some crazy angles - especially when the target is slow like eg afterburning Phantom at low speed dogfight - but not 100% perpendicular headon.

 

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1 hour ago, WreckingAres283 said:

gg, F-4E fired 9J on me, I dumped all 12 flares of my 23, AB off, 80° out turn, the missile still hits me.....if they dont fix this, MiG-23M wont be playable (or any other jet thats facing it)...

this isnt funny and has nothing to do with realism or balance.....

 

The AIM-9J is not very susceptible to flares, but which way did you turn? As flare on the miG-23 fire downwards it may be that if you turned hard into the missile your aircraft ended up between the missile and the flares, blocking the missile's view of the flares.

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2 minutes ago, Einherjer1979 said:

 

 

Also on live server R-60 has no "limited all-aspect capabilities" when we talk about clean headon.

It can hit afterburning target at some crazy angles - especially when the target is slow like eg afterburning Phantom at low speed dogfight - but not 100% perpendicular headon.

 

yeah, that's what I meant by limited all-aspect capabilities. You can't hit full frontal headons, but around 25-35 degrees off the nose of the enemy aircraft is already possible.

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3 minutes ago, Absolutely_Free said:

yeah, that's what I meant by limited all-aspect capabilities. You can't hit full frontal headons, but around 25-35 degrees off the nose of the enemy aircraft is already possible.


Same can do Aim-9J vs afterburning Mig-21, especially when it's slow. To me "limited all-aspect capabilities" is something like R-23T is going to have in the game = full frontal headon but from very short distance.*

*btw - same capabilities should have Britis RedTop but is kept nerfed.
 

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12 minutes ago, Flame2512 said:

 

The AIM-9J is not very susceptible to flares, but which way did you turn? As flare on the miG-23 fire downwards it may be that if you turned hard into the missile your aircraft ended up between the missile and the flares, blocking the missile's view of the flares.

from the F-4E / 9J perspective, I turned hard to the left side, dumping all my flares and AB off -> missile still hits me; this thing is messed up, and its not the first time this happens

 

even Magics are easier to confuse / dodge with flares

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22 minutes ago, Einherjer1979 said:


Same can do Aim-9J vs afterburning Mig-21, especially when it's slow. To me "limited all-aspect capabilities" is something like R-23T is going to have in the game = full frontal headon but from very short distance.*

*btw - same capabilities should have Britis RedTop but is kept nerfed.
 

Take it from someone who flew both the F-4E with 9Js and MiG-21SMT with R-60s, the R-60 has a much easier time locking onto targets at semi front-aspect situations. It is also a much better manouvering missile, meaning that it has easier time manouvering in those front-aspect, short distance high closure shots. Even if the 9J is able to lock onto someone from a semi-headon position, the usual high closure rate and the short distance required to actually get the missile to lock will effectively prevent the missile from hitting it's mark.

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23 hours ago, Iron_physik said:

thats not how IRCCM works

IRCCM is archived by using a Frequency modulating seeker, not a Amplitude modulation like all sidewinders had before AIM-9L

On top of the seeker the M uses smart software to filter out incorrect signals electronically.

 

the material of the sensor has nothing to with this.

 

The material of the sensor and having multiple sensors tuned to different wavelengths plays a big part in IRCCM of later sidewinder variants that used two-colour filtering to diferentiate between a flare and the intended target.

 

Early sidewinders that only used PBS detectors have no way to filter out and differentiate these signals and only could use simple tricks to detetect if a flare had been deployed, and to attempt to re-acquire the target after the flare leaves the seeker FOV or to continue on the previous flight path to attempt to intercept the target while blind. Both of which should be easily defeated if the aircraft performs any kind of moderate manuvers in an attempt to defeat the missile. These types of early IRCCM generally would only work on aircraft that were releasing flares and not performing any kind of manuvers to try and defeat the missile.

 

Spoiler

https://www.thefreelibrary.com/Advanced+infrared+missile+counter-countermeasures.-a015149906

 

IR MISSILE CCM

IR missile designers have added circuitry and signal processing to advanced IR missile seekers which detect the presence of flares and reject them as targets, allowing the seeker to continue tracking the real target. The IR counter-countermeasures (IRCCM) built into advanced missiles have two parts. The first is the "switch," which detects the flare in the seeker FOV and activates the second part, the "response" circuitry.(6) The response is the action the missile seeker takes to reject the flare.

A missile must detect a flare before initiating a counter. When a flare is detected by a seeker in an advanced IR missile, the seeker will switch on the IRCCM response to reject the flare. Both the switch and response must operate properly to successfully reject the flare and continue tracking the target.

There are many different switch and response techniques available to the missile designer. Thus, a device that is capable of decoying one advanced IR missile type may be totally ineffective against another advanced IR missile type. Switch Techniques

There are a variety of techniques which can be used to detect flares. Missiles may use one or more of the techniques to detect flares and switch on the response. If more than one technique is employed, a logic "and" or an "or" function may be used for the switch (i.e., all the techniques must be satisfied for the switch or only one of the techniques must be satisfied for the switch). Switching techniques include rise time, two-color (spectral), kinematic and spatial.

An IR missile using a rise time (temporal) switch monitors the energy level of the target it is tracking. A sharp rise in the received energy within a specified time limit indicates a flare in the seeker FOV.

Fighter aircraft have an IR signature which is much larger in the stern than on the beam or forward quadrant. Flares are designed to provide more IR energy than the target. Generally, a 2:1 ratio of flare to target (F/T) energy is desired to cause IR missiles without IRCCM to transfer lock. F/T ratios which are 2:1 in the stern can be much greater than 10:1 in the forward quadrant. A seeker with a temporal discriminator would switch on the IRCCM if the seeker detected an energy increase above a preset threshold within a preset time limit. For example, a threshold of a 2.5:1 energy increase within 40 msec might permit flare detection in all aspects, while ignoring the relatively slow energy rise from afterburner ignition. The IRCCM would be switched off when the received energy dropped to a preset value (say, 2:1) indicating the flare had left the seeker FOV.

A missile with a two-color switch samples the energy level in two or more different bands. Figure 9 shows the energy levels that might be seen by a missile tracking a target. A non-after-burning target would have more energy in band B than band A. A flare has more energy in band A than band B. Thus, a sudden jump in band A energy, compared to band B energy, indicates a flare in the seeker FOV. The seeker could use two different detectors to monitor the energy levels in the two bands (for example, lead sulfide for the short band and indium antimonide for the long band) or use a single detector with different band-pass filters on the reticle spokes.

Flares separate very quickly from the dispensing aircraft due to their high aerodynamic drag. In a beam-aspect engagement, a missile seeker which transfers track from the target to the flare will have a large, sudden change in the line-of-sight rate due to the rapid deceleration of the flare. As the seeker rapidly moves to track the flare, the kinematic switch senses the rapid change in relative motion between the missile and target and initiates the IRCCM response. Kinematic discriminators tend to have difficulty in head-on and stern engagements due to the geometry of the engagement, with the small line-of-sight rate change between the target and flare.

Advanced IR missiles with a spatial switch use the physical separation of the flare from the target to discriminate between the two. As the flares separate to the rear of the aircraft, the missile seeker will see the target on the forward side of the FOV and the flare on the rear side of the FOV. Once two hot objects on opposite sides of the FOV are distinguishable, the switch to the IRCCM mode of operation is made.

Response Techniques

The seeker's response to the switch is to reject the flare or limit its effect on target track. Generally, as long as the flare remains in the seeker FOV, the missile is not tracking the target or is tracking in a degraded mode. Most IR missile seekers have an FOV that is less than 2.5 |degrees~. At long ranges, the flare will remain in the FOV for a long time. For short-range engagements, the flare will only be in the FOV for a very short time. Several different response techniques may be used, either alone or in combination, to defeat a flare. These include simple memory, seeker push-ahead, seeker push-pull, sector attenuation, electronic FOV gating and time phase blanking.

When a simple-memory response is initiated, the missile continues the maneuver it was performing just prior to the switch. This response assumes the flare will separate to the rear of the target (a reasonable assumption for most flares). The missile rejects the seeker track data and maintains its motion relative to the target, waiting for the flare to leave the seeker FOV. The missile will continue to reject track data until the flare leaves the FOV or the switch times out, dropping the response technique and leaving the seeker in the normal track mode. If the switch times out while the flare remains in the FOV, the seeker will usually transfer lock to the flare.

The seeker push-ahead response causes the seeker gimbals to drive the seeker forward in the direction of target motion. Pushing the seeker forward causes the flare to depart the FOV faster than with simple memory, minimizing the amount of time the missile is not tracking the target. The greater the amount of push-ahead applied (degrees per second), the faster the flare will depart the FOV.

If the amount of forward bias applied is too great, the seeker may be pushed forward of the target, causing both the target and the flare to depart the FOV. The seeker may be pushed ahead without affecting the missile flight path or the missile may begin to pull a greater amount of lead on the target in concert with seeker push-ahead.

The seeker push-pull technique assumes decoy flares will have a larger IR signature than the target. The response is implemented when the flare and target are on opposite sides of the seeker FOV. Figure 10B shows a smoothed trace of the detected energy for one scan of the reticle across the detector. The received energy will rise and fall as the energy of the target and flare is scanned across the detector. When the flare energy is at a peak, the seeker gimbals drive the seeker away from the flare. When the lesser amount of energy from the target is detected, the seeker's gimbals pull the seeker in the direction of the target. The result is the seeker is moved away from the flare and toward the coolest IR target in the FOV.

In sector attenuation, an attenuation filter is placed across part of the seeker FOV. This will cause the seeker to be less sensitive to objects in that part of the FOV. If the target being tracked is in the center of the FOV, then placing an attenuator in the quadrant below and to the rear of the target should reduce any energy received from a flare. If the attenuated flare energy is below that of the unattenuated target energy, the seeker will continue to track the target. Electronic FOV gating is used in conjunction with a non-circular seeker scan pattern such as the rosette scan shown in Figure 12. At some time after the flare is dispensed, the target and flare will no longer be in the same lobe of the scan. By computing the relative motion of the target, the missile is able to determine in which lobe(s) the target should appear. Information from all the other lobes is ignored, allowing the missile to retain track on the target. Time phase blanking may be used with seekers that have multiple detector elements. An example of a multiple element array is shown in Figure 13A.(7) As the scene containing a target is scanned over the detector elements, the detectors will put out a pulse of energy when the target is detected. The time between pulses for the different detectors will remain the same for a single target centered in the FOV. The missile monitors the time relationship between pulses to ensure the seeker does not transfer lock to another target.

If a flare is dispensed from the target, the detectors will also output a pulse as the flare is scanned past the detector. However, since the flare and target do not occupy the same point in the seeker FOV, the output of the detector due to the flare will not arrive at the time the missile expects to see a pulse. The seeker only accepts pulses which arrive at the expected time and rejects all others, thereby ignoring the flare in the FOV.

 

Edited by Celestia
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7 minutes ago, Celestia said:

 

The material of the sensor and having multiple sensors tuned to different wavelengths plays a big part in IRCCM of later sidewinder variants that used two-colour filtering to diferentiate between a flare and the intended target.

 

Early sidewinders that only used PBS detectors have no way to filter out and differentiate these signals and only could use simple tricks to detetect if a flare had been deployed, and to attempt to re-acquire the target after the flare leaves the seeker FOV or to continue on the previous flight path to attempt to intercept the target while blind. Both of which should be easily defeated if the aircraft performs any kind of moderate manuvers in an attempt to defeat the missile.

 

Hide contents

https://www.thefreelibrary.com/Advanced+infrared+missile+counter-countermeasures.-a015149906

 

IR MISSILE CCM

IR missile designers have added circuitry and signal processing to advanced IR missile seekers which detect the presence of flares and reject them as targets, allowing the seeker to continue tracking the real target. The IR counter-countermeasures (IRCCM) built into advanced missiles have two parts. The first is the "switch," which detects the flare in the seeker FOV and activates the second part, the "response" circuitry.(6) The response is the action the missile seeker takes to reject the flare.

A missile must detect a flare before initiating a counter. When a flare is detected by a seeker in an advanced IR missile, the seeker will switch on the IRCCM response to reject the flare. Both the switch and response must operate properly to successfully reject the flare and continue tracking the target.

There are many different switch and response techniques available to the missile designer. Thus, a device that is capable of decoying one advanced IR missile type may be totally ineffective against another advanced IR missile type. Switch Techniques

There are a variety of techniques which can be used to detect flares. Missiles may use one or more of the techniques to detect flares and switch on the response. If more than one technique is employed, a logic "and" or an "or" function may be used for the switch (i.e., all the techniques must be satisfied for the switch or only one of the techniques must be satisfied for the switch). Switching techniques include rise time, two-color (spectral), kinematic and spatial.

An IR missile using a rise time (temporal) switch monitors the energy level of the target it is tracking. A sharp rise in the received energy within a specified time limit indicates a flare in the seeker FOV.

Fighter aircraft have an IR signature which is much larger in the stern than on the beam or forward quadrant. Flares are designed to provide more IR energy than the target. Generally, a 2:1 ratio of flare to target (F/T) energy is desired to cause IR missiles without IRCCM to transfer lock. F/T ratios which are 2:1 in the stern can be much greater than 10:1 in the forward quadrant. A seeker with a temporal discriminator would switch on the IRCCM if the seeker detected an energy increase above a preset threshold within a preset time limit. For example, a threshold of a 2.5:1 energy increase within 40 msec might permit flare detection in all aspects, while ignoring the relatively slow energy rise from afterburner ignition. The IRCCM would be switched off when the received energy dropped to a preset value (say, 2:1) indicating the flare had left the seeker FOV.

A missile with a two-color switch samples the energy level in two or more different bands. Figure 9 shows the energy levels that might be seen by a missile tracking a target. A non-after-burning target would have more energy in band B than band A. A flare has more energy in band A than band B. Thus, a sudden jump in band A energy, compared to band B energy, indicates a flare in the seeker FOV. The seeker could use two different detectors to monitor the energy levels in the two bands (for example, lead sulfide for the short band and indium antimonide for the long band) or use a single detector with different band-pass filters on the reticle spokes.

Flares separate very quickly from the dispensing aircraft due to their high aerodynamic drag. In a beam-aspect engagement, a missile seeker which transfers track from the target to the flare will have a large, sudden change in the line-of-sight rate due to the rapid deceleration of the flare. As the seeker rapidly moves to track the flare, the kinematic switch senses the rapid change in relative motion between the missile and target and initiates the IRCCM response. Kinematic discriminators tend to have difficulty in head-on and stern engagements due to the geometry of the engagement, with the small line-of-sight rate change between the target and flare.

Advanced IR missiles with a spatial switch use the physical separation of the flare from the target to discriminate between the two. As the flares separate to the rear of the aircraft, the missile seeker will see the target on the forward side of the FOV and the flare on the rear side of the FOV. Once two hot objects on opposite sides of the FOV are distinguishable, the switch to the IRCCM mode of operation is made.

Response Techniques

The seeker's response to the switch is to reject the flare or limit its effect on target track. Generally, as long as the flare remains in the seeker FOV, the missile is not tracking the target or is tracking in a degraded mode. Most IR missile seekers have an FOV that is less than 2.5 |degrees~. At long ranges, the flare will remain in the FOV for a long time. For short-range engagements, the flare will only be in the FOV for a very short time. Several different response techniques may be used, either alone or in combination, to defeat a flare. These include simple memory, seeker push-ahead, seeker push-pull, sector attenuation, electronic FOV gating and time phase blanking.

When a simple-memory response is initiated, the missile continues the maneuver it was performing just prior to the switch. This response assumes the flare will separate to the rear of the target (a reasonable assumption for most flares). The missile rejects the seeker track data and maintains its motion relative to the target, waiting for the flare to leave the seeker FOV. The missile will continue to reject track data until the flare leaves the FOV or the switch times out, dropping the response technique and leaving the seeker in the normal track mode. If the switch times out while the flare remains in the FOV, the seeker will usually transfer lock to the flare.

The seeker push-ahead response causes the seeker gimbals to drive the seeker forward in the direction of target motion. Pushing the seeker forward causes the flare to depart the FOV faster than with simple memory, minimizing the amount of time the missile is not tracking the target. The greater the amount of push-ahead applied (degrees per second), the faster the flare will depart the FOV.

If the amount of forward bias applied is too great, the seeker may be pushed forward of the target, causing both the target and the flare to depart the FOV. The seeker may be pushed ahead without affecting the missile flight path or the missile may begin to pull a greater amount of lead on the target in concert with seeker push-ahead.

The seeker push-pull technique assumes decoy flares will have a larger IR signature than the target. The response is implemented when the flare and target are on opposite sides of the seeker FOV. Figure 10B shows a smoothed trace of the detected energy for one scan of the reticle across the detector. The received energy will rise and fall as the energy of the target and flare is scanned across the detector. When the flare energy is at a peak, the seeker gimbals drive the seeker away from the flare. When the lesser amount of energy from the target is detected, the seeker's gimbals pull the seeker in the direction of the target. The result is the seeker is moved away from the flare and toward the coolest IR target in the FOV.

In sector attenuation, an attenuation filter is placed across part of the seeker FOV. This will cause the seeker to be less sensitive to objects in that part of the FOV. If the target being tracked is in the center of the FOV, then placing an attenuator in the quadrant below and to the rear of the target should reduce any energy received from a flare. If the attenuated flare energy is below that of the unattenuated target energy, the seeker will continue to track the target. Electronic FOV gating is used in conjunction with a non-circular seeker scan pattern such as the rosette scan shown in Figure 12. At some time after the flare is dispensed, the target and flare will no longer be in the same lobe of the scan. By computing the relative motion of the target, the missile is able to determine in which lobe(s) the target should appear. Information from all the other lobes is ignored, allowing the missile to retain track on the target. Time phase blanking may be used with seekers that have multiple detector elements. An example of a multiple element array is shown in Figure 13A.(7) As the scene containing a target is scanned over the detector elements, the detectors will put out a pulse of energy when the target is detected. The time between pulses for the different detectors will remain the same for a single target centered in the FOV. The missile monitors the time relationship between pulses to ensure the seeker does not transfer lock to another target.

If a flare is dispensed from the target, the detectors will also output a pulse as the flare is scanned past the detector. However, since the flare and target do not occupy the same point in the seeker FOV, the output of the detector due to the flare will not arrive at the time the missile expects to see a pulse. The seeker only accepts pulses which arrive at the expected time and rejects all others, thereby ignoring the flare in the FOV.

 

pls read your own source, because it disagrees with your statement, sensor material has no effect on IRCCM

 

its all electronically filtered, otherwise the AIM-9L also would have IRCCM, because it uses the same sensor material as the 9M

Only the 9M got IRCCM electronic mounted to it, according to the Sidewinder book by Ron westrum

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23 minutes ago, Iron_physik said:

pls read your own source, because it disagrees with your statement, sensor material has no effect on IRCCM

 

its all electronically filtered, otherwise the AIM-9L also would have IRCCM, because it uses the same sensor material as the 9M

Only the 9M got IRCCM electronic mounted to it, according to the Sidewinder book by Ron westrum

 

Does it? I cant find it.

The part in my spoiler specifically refers to needing to use multiple detectors that search at different wavelengths to perform two colour filtering. (The type of IRCCM introduced on the 9M)

The PBS detector has a very narrow band that it sees and would require an Insb detector in conjunction to be able to perform the filtering you are talking about.

You physically cannot perform electronic filtering without having at least two electrical signals/frequencies to compare against.

 

The 9M had Improved countermeasure resistance over the 9L, The latter still had some of the aformentioned countermeasure resistance techniques, but the 9M introduced the two colour filtering wich greatly improved the ability to hit manuvering targets that were using flares.

 

Back to the ORIGNAL point - The Aim-9J should have no more or less IRCCM than the Aim-9D, or even the AIM-9E, because the only things I can see what were improved on the 9J were:

  • using partial solid state electronics
  • improved actuators,
  • a new motor
  • Square Tipped Cannards

 

If you can give me any reason for the 9J to have the incredible IRCCM it has in game, please say it, because I can find nothing mentioning IRCCM on the AIM-9J at all.

Edited by Celestia
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4 minutes ago, Celestia said:

 

Does it? I cant find it.

The 9M had Improved countermeasure resistance over the 9L it did not introduce it. The latter still had countermeasure resistance, but the 9M introduced the two colour filtering wich greatly improved the ability to hit manuvering targets that were using flares.

 

 

"The new Microchip electronics gave the missile enough processing power to sort out false targets, both background and countermeassures, from the real ones"

Sidewinder Creative Missile Development at China lake - Ron Westrum - page 197

 

on the same page it mentions different filter materials on the 9L PIP (prototype 9M) which only gave very limited CCRM against older flare types, but thats NOT attributed to the Sensor, thats attributed to using a different Dome material to filter out specific wavelenghts before they can reach the sensor.

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