F5E countermeasures vs SA-3

[Reflected]

I set up a mission where I can spawn random SAM sites to do some wild weaseling with he F5. My problem is that no matter what I do I cannot defeat the SAMs. It seems that countermeasures don't affect it AT ALL. F5 countermeasures are quite efficient against the MIG-21, but SAMs don't even budge. Why is this?

 

The mission file can be downloaded here:

https://www.digitalcombatsimulator.com/en/files/2247486/

[VTJS17_Fire]

I defeated a SA-3 missile with chaff in my M-2000, yesterday. I'll upload the Tacview track later.

 

But you're right. Chaff isn't that effective like in real life.

[Beamscanner]

The real life Low Blow radar uses a technique known as 'leading edge tracking', in which case the closest part of the reflection is the part that gets tracked.

 

So unless you are jamming, which can mask the the leading edge of a target, the SA-3 can still engage you if you fly in front of your chaff. Though your wingman behind you should be ok!! haha

 

Anyway, the SA-3 is still widely used. If chaff was that effective against it, the SA-3 wouldn't still be in service.

[red_coreSix]

Chaff works perfectly against SA-3s, you just gotta be beaming it so the leading edge tracker has no effect, as Beamscanner pointed out.

[Reflected]

Chaff works perfectly against SA-3s, you just gotta be beaming it so the leading edge tracker has no effect, as Beamscanner pointed out.

 

Can you please elaborate? I usually put the SAM site on my 9 or 3, and do split S maneuvers while pumping out chaff. This doesn't seem to work at all. That leading edge tracking thing is still not entirely clear. Thanks!

[red_coreSix]

Not sure if it's specific to the F-5 as I don't own it, but I've been able to defeat 100% of missiles launched at me by notching and chaffing.

 

A leading edge tracker tracks the leading edge of the skin return, as opposed to a centroid tracker which tracks the average center of the return. This is an ECCM technique to reduce the effect of chaff and some ECM techniques. It's usually used in conjunction with PRF jitter.

[Reflected]

Not sure if it's specific to the F-5 as I don't own it, but I've been able to defeat 100% of missiles launched at me by notching and chaffing.

 

A leading edge tracker tracks the leading edge of the skin return, as opposed to a centroid tracker which tracks the average center of the return. This is an ECCM technique to reduce the effect of chaff and some ECM techniques. It's usually used in conjunction with PRF jitter.

 

Thanks! The thing is, I'm also able to defeat SAMs with every plane by notching and chaffing, except the F5E. This is what I find weird..

[red_coreSix]

Strange indeed, can you post a tacview so we can have a look?

[OnlyforDCS]

Please correct me if Im wrong but AFAIK "notching" doesn't work against ground based radars.

[Reflected]

Please correct me if Im wrong but AFAIK "notching" doesn't work against ground based radars.

 

Whatever that means, I meant I always put it on my 3 or 9.

[red_coreSix]

It does, ground based radars still have a notch to eliminate ground movers. The notch might be disabled when in look-up, similarly to fighter radars but it's there.

Doesn't really apply here though, the point is that chaff is more effective when beaming because LET doesn't have an effect.

[OnlyforDCS]

Yes, well we are talking about fighters here aren't we? By definition a ground based radar will always be looking up at airborne threats. So putting the enemy SAM radar on your 3 or 9 o clock will not help you in any case.

 

Like red_CoreSix says, you need to beam the radar (turn directly aways from it) and pump out chaff for the missile to lose track.

[red_coreSix]

Yes, well we are talking about fighters here aren't we? By definition a ground based radar will always be looking up at airborne threats. So putting the enemy SAM radar on your 3 or 9 o clock will not help you in any case.

 

Like red_CoreSix says, you need to beam the radar (turn directly aways from it) and pump out chaff for the missile to lose track.

 

Fighters can fly low, no? There can be mountains behind the fighter causing look-down even in a "look-up" geometry.

BTW, "beaming" means putting the radar at your 3 or 9. Notching is the effect beaming has on a doppler radar.

[ESAc_matador]

Flying low...getting into the minimum radius... best chance. I think, the lack of speed is the key to make it difficult to avoid SAMs.

[WinterH]

Haven't flown in a while, but in my experience, SA-3 in DCS can only hit in a very narrow band of altitude, go lower, it misses, go fighter, it very often misses.

 

May be that's changed in newer versions don't know...

 

Also, in DCS, SAM crews aren't particularly bright fellows, the commander who shot the F-117 down, they are not :). They tend to fire in or around their maximum range, and often you can just beam it or turn back as soon as you get a launch warning. Therefore, unless the SAM site has a a boatload of ready launcers, it isn't too difficult to just bait them into wasting their missiles.

[OnlyforDCS]

BTW, "beaming" means putting the radar at your 3 or 9. Notching is the effect beaming has on a doppler radar.

 

Yes you are correct, my mistake.

[Beamscanner]

Low Blow is not a pulse doppler radar bro.. There is no doppler notch...

 

putting it at your 3 or 9 wont do much... Try doing a split S while dumping chaff.

 

For the chaff to be effective it needs to be at roughly the same bearing and closer in range to the low blow tracking radar.. Dumping chaff and then flying away from it (in azimuth) doesn't help you.

 

 

Also, the SA-3 was designed to enable it to engage low altitude targets, filling the low alt gap the SA-2 couldn't.

[red_coreSix]

In-game it's a doppler. So notching is the way to go as far is the game is concerned.

 

Realistically beaming will still work against leading edge tracker.

[Beamscanner]

In-game it's a doppler. So notching is the way to go as far is the game is concerned.

 

Realistically beaming will still work against leading edge tracker.

 

Thats sad to hear..

 

IRL beaming isn't effective against a SA-3...

 

1. The SA-3 has a relatively short range. If the target drops chaff at a bearing of 090, beams the SA-3 at these short ranges then it will rapidly change its bearing from the radar. Seconds after dropping chaff the target will be at a bearing of 093 while the chaff is still at 090. This change in bearing means that the main beam of the radar (which is fundamentally narrow, but even more-so at short ranges) moves outside of the chaff bundle, making it less effective.

 

2. The SA-3 operators use 'A-scopes' that allow them to distinguish aircraft skin returns from chaff. The chaff return has an intense increase in amplitude, while an aircraft skin return has a more gradual increase in amplitude over time, due to certain parts of the air-frame being more reflective than others.

 

Jamming+Chaff is the best way to defeat older SAMs as well as downward vertical maneuvers.

 

An Australian think tank states that the Low blow has a single shot Pk of 50-90% if the target uses chaff. That's extremely good for a 1961 SAM, and probably explains why this 6nm SAM has proliferated around the world.

http://www.ausairpower.net/APA-S-125-Neva.html

Edited May 11, 2017 by Beamscanner

[red_coreSix]

The same source states a 20-50% Pk against a "maneuvering target", with no chaff mentioned. Very ambiguous figures...

 

Beaming will still have several effects on the SA-3.

It will deny a leading edge tracker, making chaff more effective (right after deployment, shifting the centroid).

It will force the missile to pull maximum lead.

 

Not so sure what jamming will do at the short ranges the SA-3 operates in. The low blow has a 270kw peak power rating.

[Eddie]

Thats sad to hear..

 

IRL beaming isn't effective against a SA-3...

 

1. The SA-3 has a relatively short range. If the target drops chaff at a bearing of 090, beams the SA-3 at these short ranges then it will rapidly change its bearing from the radar. Seconds after dropping chaff the target will be at a bearing of 093 while the chaff is still at 090. This change in bearing means that the main beam of the radar (which is fundamentally narrow, but even more-so at short ranges) moves outside of the chaff bundle, making it less effective.

 

2. The SA-3 operators use 'A-scopes' that allow them to distinguish aircraft skin returns from chaff. The chaff return has an intense increase in amplitude, while an aircraft skin return has a more gradual increase in amplitude over time, due to certain parts of the air-frame being more reflective than others.

 

Jamming+Chaff is the best way to defeat older SAMs as well as downward vertical maneuvers.

 

This.

 

The Low Blow has an azimuth resolution cell of just over 600 feet at 6 nautical miles, so a beaming aircraft travelling at 300 knots will be distinct from any chaff after just over a second. If you could combine a very high dispense rate of chaff and jamming (unlikely as few SPJs cover the side hemispheres) while placing the TTR on the beam it might have a greater than zero chance of being successful, but it won't be very likely.

 

That said, while you won't necessarily decoy the missile, you might generate sufficient miss distance to survive the shot by causing the missile not to fuse and/or being outsider of its lethal radius. Sadly, both things that DCS doesn't seem to model.

 

Either way dragging the missile would be far more effective as not only would your chaff effectively obscure your skin return from the TTR, it'd also bring your SPJ fully into play. Although the SA-3 isn't too bad when it comes to ECCM with the leading edge tracking doing a good job of defeating an RGPO.

 

How I wish this stuff mattered in DCS at all.

[red_coreSix]

Either way dragging the missile would be far more effective as not only would your chaff effectively obscure your skin return from the TTR, it'd also bring your SPJ fully into play. Although the SA-3 isn't too bad when it comes to ECCM with the leading edge tracking doing a good job of defeating an RGPO.

 

How I wish this stuff mattered in DCS at all.

 

I agree that dragging is the overall better choice, but do you always have the time when getting shot at from close range? Beaming is a good choice when you don't have time to turn cold.

 

The leading edge tracking won't do much against a repeater jammer unless the low blow has some sort of PRF jitter and/or frequency hopping.

[Beamscanner]

I agree that dragging is the overall better choice, but do you always have the time when getting shot at from close range? Beaming is a good choice when you don't have time to turn cold.

 

The leading edge tracking won't do much against a repeater jammer unless the low blow has some sort of PRF jitter and/or frequency hopping.

 

Jamming can be used to degrade or remove the Low Blow Operators ability to distinguish the true skin return from the chaff with the A-scope. Making the chaff more effective.

 

Beaming is of course more reliable than flying straight towards the Low Blow, but typically people on this forum expect a beam maneuver to completely mask them like it might in a look-down doppler notch scenario against a pulse doppler airborne radar. Not the case for this pulse radar designed to track low altitude targets. And as has been stated, the azmiuth cell in small, so the chaff bundle only applies to the res. cell its located in (yes chaff can degrade the S/N ratio via sidelobes, but not enough to mask a beaming target) and when your jet runs through a res cell every second, the chaff wont help you very much.

 

The 'trick' isnt to remove the leading edge tracker from the equation. Its to make it work against the radar. By dumping chaff as you reverse your range, the radar will hold onto the chaff bundle because its the closest return at that bearing. Add some jamming, and now the operator will struggle to identify the true skin return when the aircraft moves to another range cell. Meaning that the target becomes very hard to locate even after it gets some range separation from the chaff.

 

 

Regardless of what AUS Air power says, the SAM has in fact proliferated around the world and is still in use by many nations.. This would not be true if chaff was effective in practice.

 

In regards to the OP

Without an on board jammer or active decoy the F-5E is going to struggle to defeat this SAM. A beam is not as effective as it is against pulse doppler radars at higher altitudes. Try range reversals and changing your altitude. The missile will waste just as much energy trying to lead you if change your flight path in the vertical as it would if you changed direction in the horizontal. though, with the downward maneuver it has the chance to crash into terrain.

Edited May 12, 2017 by Beamscanner

[red_coreSix]

Jamming can be used to degrade or remove the Low Blow Operators ability to distinguish the true skin return from the chaff with the A-scope. Making the chaff more effective.

 

You keep mentioning operators, out of curiosity, doesn't the SA-3 typically employ an auto-tracker, AGC and doesn't require much input post-launch? Or are you talking about a manual launch, via CLOS?

 

The 'trick' isnt to remove the leading edge tracker from the equation. Its to make it work against the radar. By dumping chaff as you reverse your range, the radar will hold onto the chaff bundle because its the closest return at that bearing. Add some jamming, and now the operator will struggle to identify the true skin return when the aircraft moves to another range cell. Meaning that the target becomes very hard to locate even after it gets some range separation from the chaff.

 

If the radar is capable of leading edge tracking it could easily switch to trailing edge tracking in such a case, couldn't it? I imagine that makes it quite vulnerable to ECM though...

[GGTharos]

Leading/Trailing edge is operator selectable usually.

 

In any case, I don't see why 'leading edge tracking' would make beaming ineffective. Mentioning the chaff-bundle separating rapidly is fair, but we've seen much more modern radars track chaff instead of target at quite short (gunsgunsguns :) ) ranges on this very forum.

 

If the chaff blooms fast enough, the centroid will shift - and in my understanding, leading edge tracking doesn't have too much much to do with the power centroid ... since the chaff's overwhelming reflection will arrive at the same time as target skin reflection.

 

I would say beaming+CM is one of the most effective countermeasures by itself, though I also agree that adding maneuver to the mix should make it even more effective.