SAM evasion practice

[Topgun505]

It would seem the discussion could be clarified dramatically if someone were to make a video of the technique GGTharos is referring to. Anyone got FARPS and want to give it a go?

[Bushmanni]

My conclusion based on my tests is that the orthogonal roll is more likely to save my butt in any situation as its easy to do and doesn't require perfect timing. If in doubt you just beam the missile and start doing split-S repeatedly. Turning into the missile is better in theory only in certain situations.

 

Simulation issue. Some older missiles can be vulnerable to this (not very maneuverable or old guidance system, or both), but in general - not way you want to learn missile evasion. Bad habit.

[MBot]

No, you pull away out of plane. Any in-plane turn = doom ;)

 

I am not so big into missile dynamics. Doesn't that only apply to missiles that employ proportional navigation? What about LOS riders like SA-8, SA-19 or Roland. Since they fly a pure pursuit, wouldn't a turn into the missile force the biggest g-problem on it?

 

Edit: Doesn't apply to DCS A-10C, as it doesn't feature LOS guidance for missiles as far as I know.

Edited April 11, 2011 by MBot

[GGTharos]

They don't fly pure pursuit. There are no SAMs that do so as of WW2. They all aim for lead pursuit, though certainly homing missiles might have the advantage.

[MBot]

A lot of SAMs are Command Line Of Sight guided. In DCS these are (to the best of my kndowledge) SA-3, SA-8, SA-19 and Roland. The SA-15 is command guided too, but I don't know if it flies LOS (at least when guiding with the optical backup system).

 

Thinking about it they don't actually fly true pure persuit, but they certainly don't fly lead persuit.

Edited April 11, 2011 by MBot

[GGTharos]

You mean they don't fly proportional. They do fly lead though.

 

Thinking about it they don't actually fly true pure persuit, but they certainly don't fly lead persuit.

[bloomstomb]

Yep, the JMR will switch back into standby mode after successfully breaking a lock. That way he doesn't have enough time to home-in on your jammer.

 

It switches back into stby mode even if you dont break a lock. Try it on the runway, same results.

[MBot]

Yes you are right, I wasn't very precise with the terms. Against an unmaneuvering target a CLOS missiles flies a pure pursuit at launch, shifts into lead and finally reaches a collision course at the moment of impact.

 

But to get back to the point, how does CLOS guidance, which is still very common, affect the optimal last ditch maneuver?

[bloomstomb]

I dont know, I never had trouble avoiding sams this game. Just make it a high deflection shot,90 degrees to the missle. Fire off a couple flares and chaffs when missle is close enough and you are ok, oh and keep e level high. So dont go climbing, unless you are out of the range of anyway.

Edited April 11, 2011 by bloomstomb

[GGTharos]

You'd think it would make it easier, but I don't really know. Even a CLOS missile can react quite quickly, and it can be sent a burst command from the launcher/command station automatically, possibly achieving damage or a kill a bit outside of a homing weapon's + fuze capability. Possibly. :)

 

But to get back to the point, how does CLOS guidance, which is still very common, affect the optimal last ditch maneuver?

[GGTharos]

Just make it a high deflection shot

 

... what?

[MBot]

Ok, let's assume it is a simple Rapier SAM with a contact fuse :) Maneuver in or out of plane to (have the best hopes to) kinematically defeat it? I guess it also depends on the state of the engagement, as the orientation of the missile in relation to the target changes considerably the longer the flight time.

[GGTharos]

You still want out-of-plane. Regardless of the guidance system used, that should still cause the most problems. :)

 

There are some exceptions but they have to do with very old missiles - for example, vietnam-era SA-2's were very vulnerable to a robust diving maneuver, but that was fixed (they would try to beat you to the ground :) )

They were also not very maneuverable, so as long as you could see them you could beat'em in just about any reasonable manner you chose.

 

 

Ok, let's assume it is a simple Rapier SAM with a contact fuse :) Maneuver in or out of plane to (have the best hopes to) kinematically defeat it? I guess it also depends on the state of the engagement, as the orientation of the missile in relation to the target changes considerably the longer the flight time.

[bloomstomb]

... what?

 

It just means you want to make that missile lead as much as possible to bear on you. So generally I try to fly 90 deg perpendicular, with a high e state.

 

Its ww2 online/ rise of flight/ aces high/ terminology.

Edited April 11, 2011 by bloomstomb

[asparagin]

But to get back to the point, how does CLOS guidance, which is still very common, affect the optimal last ditch maneuver?

 

Considering the orthogonal roll, I think CLOS guidance doesn't affect it, in a positive or negative manner, just because of the stage where you have to take action: terminal. The game is pretty much set at that point, the missile already knows where it will explode so to speak, it just has to get there. (that's why: last ditch maneuver). Well my understanding, that is.

[MBot]

You still want out-of-plane. Regardless of the guidance system used, that should still cause the most problems. :)

 

I am still not entierly conviced. You are close, but I need some more explanation :)

 

I tried to make some sketches, but the 3 dimensional stuff makes my head spin. I try to look at this that way. A PN missile on the 3/9 close to impact is on a collision course and does not need to pull any Gs unless you maneuver. If you pull into the missile, the angular rate you have from missile POV will be small, therfore the adjustment of the missileflightpath to get back to collision course is small too. If you pull up, your angular rate is bigger.

 

So let's try a CLOS missile on your 3/9. It won't be on a collision course and requires to pull constant G to remain in the LOS, the more the closer it gets to the target. Now wouldn't it be smart to pull into the missile to make it pull even harder into you than it has to anyway?

[GGTharos]

It will work the same way as it does for the PN missile. Again, just because the missile is CLOS does not imply it is following pure pursuit in any way, shape or form. The beam it's riding is more than likely aimed at the collision point or guiding the missile to the collision point (it depends on whether you're using a simple or complex trajectory, which in turn depends on intercept distance) and it has been this way at least since NIKE.

 

You have one radar tracking the target, guiding the missile (ie. forming the beam it flies in). They don't have to be aimed in the same direction ... and you can probably fake PN this way well enough, but that's just a guess on my part :)

 

I am still not entierly conviced. You are close, but I need some more explanation :)

 

I tried to make some sketches, but the 3 dimensional stuff makes my head spin. I try to look at this that way. A PN missile on the 3/9 close to impact is on a collision course and does not need to pull any Gs unless you maneuver. If you pull into the missile, the angular rate you have from missile POV will be small, therfore the adjustment of the missileflightpath to get back to collision course is small too. If you pull up, your angular rate is bigger.

 

So let's try a CLOS missile on your 3/9. It won't be on a collision course and requires to pull constant G to remain in the LOS, the more the closer it gets to the target. Now wouldn't it be smart to pull into the missile to make it pull even harder into you than it has to anyway?

[MBot]

It will work the same way as it does for the PN missile. Again, just because the missile is CLOS does not imply it is following pure pursuit in any way, shape or form. The beam it's riding is more than likely aimed at the collision point or guiding the missile to the collision point (it depends on whether you're using a simple or complex trajectory, which in turn depends on intercept distance) and it has been this way at least since NIKE.

 

You have one radar tracking the target, guiding the missile (ie. forming the beam it flies in). They don't have to be aimed in the same direction ... and you can probably fake PN this way well enough, but that's just a guess on my part :)

 

Well I am certain that for Rapier the beam is aimed directly at the target and I am pertty sure that this is also the case for the other older short range systems like Roland and SA-8. Since for many systems the distance to the missile (and sometimes even the target) is unknown, this is needed to ensure a hit. Perhaps the SA-15 with it's fancy radar is capable of such stunts.

 

 

But I have thought it over again and tried to look at it from the launchers point of view. If the target pulls into the missile (and also the launcher since launcher-missile-target are on one line), then the angular rate of the target decreases. So also the rate the beam rotates decreases, which means the missile is relieved from some of the Gs it would otherwise have to pull to stay inside the beam. So pulling inside the missile actualy helps it to stay in the LOS. Pulling up otherwise further increases the angular rate as viewed from the launcher.

 

Or something like that, that is more of a feeling than hard math :)

[GGTharos]

Yeah, it's conceptually easy I suppose - or - visually.

 

As for following pure - it really depends on the system, but I haven't seen any evidence that the SA-8 does such a thing AFAIK. I don't know much about Rapier, the closest I can think of is the SA-19, but even that has an upgrade to make it more capable against aircraft :)

 

Edit: At least according to wikipedia (I know, great source huh :D ) the SA-8 has a radar decicated for tracking the missile. Getting some exact specs on the whole thing would be nice :)

Edited April 11, 2011 by GGTharos

[MBot]

Edit: At least according to wikipedia (I know, great source huh :D ) the SA-8 has a radar decicated for tracking the missile. Getting some exact specs on the whole thing would be nice :)

 

Here is an excellent description of the system from the East German Army (in German):

 

http://www.flak11.de/9K33-Start.htm

 

The missile is guided in 3 phases by different beams. The last and narrowest beam is formed by the target tracking radar, so at least in the terminal phase the missile is in LOS. The flightpath of the missile when guided by the missile tracking radar is unclear.

Edited April 11, 2011 by MBot

[GGTharos]

I found the manual for it, but it's all in Russian :(