Selecting flares and chaff in loadout - question

[JazonXD]

I'm wondering why in the F-15 and many other aircraft, when you try to increase the number of flares, the chaff count goes down by double, kinda implying that the flare bundles are twice the size of chaff bundles? I don't know what these "bundles" even look like or how they are stored or how they work, but can someone give me an explanation?

 

Thanks.

[GGTharos]

Your guess is correct in a way. Countermeasures are usually installed in buckets, which can hold a certain amount of a given type of CM. You get 30 chaff per bucket and 15 flares per bucket.

[JazonXD]

Your guess is correct in a way. Countermeasures are usually installed in buckets, which can hold a certain amount of a given type of CM. You get 30 chaff per bucket and 15 flares per bucket.

 

Ahh interesting. So basically each flare bundle takes up double the space compared to chaff in every bucket?

[Sweep]

Right.

 

We have the the big flares modeled. I wish we had small flares (the M206s, I think?), man...

[JazonXD]

Right.

 

We have the the big flares modeled. I wish we had small flares (the M206s, I think?), man...

 

What advantage would the smaller flares have? Wouldn't their effectiveness also be reduced?

[GGTharos]

Depends on what's tracking you ... there are no flares that can decoy an AIM-9X for example, except in one very specific case with a very specific flare type ... and that's only because it covers a large enough area to hide the target from dead astern, thus giving it a bit of time to maneuver.

 

The slightly less modern (today) rosette seekers have a target number limitation, so your flare could in theory be smaller, but if it's good enough to be counted as a target, it will count against the 6-8 target memory ... drop 10 flares and the miss is guaranteed when combined with the right maneuver.

[JazonXD]

Depends on what's tracking you ... there are no flares that can decoy an AIM-9X for example, except in one very specific case with a very specific flare type ... and that's only because it covers a large enough area to hide the target from dead astern, thus giving it a bit of time to maneuver.

 

The slightly less modern (today) rosette seekers have a target number limitation, so your flare could in theory be smaller, but if it's good enough to be counted as a target, it will count against the 6-8 target memory ... drop 10 flares and the miss is guaranteed when combined with the right maneuver.

 

Ahh interesting. Just out of curiosity, how do those rosette seekers work to provide counter countermeasure? They'd detect 6-8 targets because someone dropped flares but how does it know which one of those flares is the original? (obviously, you probably can't go into detail because those are how specifically those systems work. However, what about a general idea?)

[GGTharos]

I can't go into detail because I don't know the actual algos, but I understand the idea behind them on a very high level.

 

The simplest idea is that you can set up an algorithm to reject/delete targets based on some criteria, and to not detect based on other criteria.

 

Just to give a very simple example, suppose you're tracking an aircraft moving in a specific direction. In this case, you can bias the algo to reject anything that moves in the opposite direction ( ... cue 'smart' flares to the rescue, that sort of fly along your plane for a bit :) ).

You can basically delete those targets after noticing they're moving 'wrong' in comparison to the original target aircraft.

 

But suppose someone releases a string of flares. Rosette seekers create a pseudo-image, but just like their progenitors, they don't build a real, high resolution image at all. So now they have a 'string' of a target (not a bunch of distinct targets) ... basically a centroid. The missile seeker will attempt to aim for the middle of that, and now it's decoyed. This isn't modeled in DCS, but if it was - flares would be highly effective against non-FPA seekers when used in quantity and with maneuver, as they ought to be.

I'm not sure that there is going to be any effort to model such ECM/ECCM though - that's up to ED, and it's certainly not a simple task.

 

BTW, you can use similar functionality for radar guided missiles, though they might have more means to perform ECCM.

 

Ahh interesting. Just out of curiosity, how do those rosette seekers work to provide counter countermeasure? They'd detect 6-8 targets because someone dropped flares but how does it know which one of those flares is the original? (obviously, you probably can't go into detail because those are how specifically those systems work. However, what about a general idea?)

[Nerd1000]

I can't go into detail because I don't know the actual algos, but I understand the idea behind them on a very high level.

 

The simplest idea is that you can set up an algorithm to reject/delete targets based on some criteria, and to not detect based on other criteria.

 

Just to give a very simple example, suppose you're tracking an aircraft moving in a specific direction. In this case, you can bias the algo to reject anything that moves in the opposite direction ( ... cue 'smart' flares to the rescue, that sort of fly along your plane for a bit :) ).

You can basically delete those targets after noticing they're moving 'wrong' in comparison to the original target aircraft.

 

But suppose someone releases a string of flares. Rosette seekers create a pseudo-image, but just like their progenitors, they don't build a real, high resolution image at all. So now they have a 'string' of a target (not a bunch of distinct targets) ... basically a centroid. The missile seeker will attempt to aim for the middle of that, and now it's decoyed. This isn't modeled in DCS, but if it was - flares would be highly effective against non-FPA seekers when used in quantity and with maneuver, as they ought to be.

I'm not sure that there is going to be any effort to model such ECM/ECCM though - that's up to ED, and it's certainly not a simple task.

 

BTW, you can use similar functionality for radar guided missiles, though they might have more means to perform ECCM.

 

I read that are also some that use a UV sensor alongside the IR one- I guess the seeker will only track IR signatures that are not accompanied by a UV signature. the counter to that strategy is making a flare that is larger but operates at a lower temperature.

[GGTharos]

Yes, there are dual sensor missiles - actually, most of them are dual sensor now. I've read a whole bunch of stuff about what the UV sensor is used for, but in the end correct employment of flares = 100% decoy.

 

That said, 'correct employment' is not really well understood ... I have some ideas, I've seen some studies, and I've heard some vague things as well, but there isn't a huge lot of information about modern missiles. There is some if you can find it about older missiles, as well as recent studies pretty much stating flares=decoy, as long as you employ enough of them and in most cases, maneuver appropriately.

 

If you recall, an F-15 chased down an after-burning MiG-25, and he decoyed every sidewinder that was shot at him.