Air-to-Air Missile Discussion

[danilop]

:doh:

[GGTharos]

So in other words, you don't actually have a clue and you're just talking because you felt like talking.

 

Ok. :D

 

:doh:

[Mandrake5]

No, it wasn't done to 'appease the red whiners', and frankly if you don't understand how difficult it is to tune missiles properly, I'd thank you to can the attitude, yesterday.

 

Missiles were tuned based on available data which included some performance points but not other (also useful) performance points. Credible reference to such things was not found until rather close to release, so things have stayed as they are for 1.2.3.

 

These issues affect all missiles, not just the 120. In this iteration, the SRM's perform (or should perform) a lot better than previously - they were a big part of the learning curve.

 

 

No offence intended, I assure you (but don't you think you might deserve just a teeny bit of attitude for this? After all, the entire F15 fleet in Georgian theatre just got grounded).

[danilop]

So in other words, you don't actually have a clue and you're just talking because you felt like talking.

 

Ok. :D

 

I would like to meet person from this forum who has a clue about missile performance apart from internet /declasiffied manuals / university / etc ... Real missile parameters, that is ...

 

P.S.

I admit - don't have a clue, beside sources already mentioned! :)

[GGTharos]

No, I don't think so. And to be clear, the devs weren't wrong to assume what they did assume, because unless you have good performance data, you can make a missile reach a certain range in many ways - you could burn the rocket enough to go mach 1 for 30nm, or you could burn it all in a few seconds and sprint up to M4.

 

But there are other issues as well - can you correctly guess the fuel fraction, and its specific impulse, do we know how the different propellant grains burn (together, separately? ... ) etc.

 

Like I said, it's a significant learning curve.

[GGTharos]

What's wrong with declass manuals? You have a problem with declassified data? Do you have some classified data to offer up?

 

How about something like this? I'm sorry though, it's declassified AND a university/missile research paper, how sad :(

 

 

 

I would like to meet person from this forum who has a clue about missile performance apart from internet /declasiffied manuals / university / etc ... Real missile parameters, that is ...

 

P.S.

I don't have a clue, beside sources already mentioned!

[Aries]

Wait! So you say I can rush my Hawg now head to head on a Flanker and spank him with my hissing Sidewinders? :D

[GGTharos]

Sidewinders are indeed performing better in this iteration, the short range heaters have had their performance significantly improved in 1.2.3, and I think players will be pleased with the R-73 and AIM-9.

 

Wait! So you say I can rush my Hawg now head to head on a Flanker and spank him with my hissing Sidewinders? :D

[danilop]

What's wrong with declass manuals? You have a problem with declassified data?

 

...

 

No GG, don't have any problem with that ... it's just the notion that you usually declassify old technology which is not important and valid anymore. ;)

 

It all boils down to what you want to model. AIM120C is easier in that regard than any of the Russian design simply because more (not all! ;)) stuff is publicly available.

 

I just don't understand why did you attack me personally :( ? I think that ARH and AI is behaving more "realistically" (so there you go - all this ongoing debate about missiles is in essence talking about different "realities" - simply there are no hard data to define "realism" outside classified circles) in this patch than in 1.2.2 and if you carefully read my original post, it stresses only that.

 

You don't think that 1.2.3 is improvement over 1.2.2?

Edited February 27, 2013 by danilop

[SkateZilla]

is the TWS Mode in the -29 working with the R77?

[Eddie]

I would like to meet person from this forum who has a clue about missile performance apart from internet /declasiffied manuals / university / etc ... Real missile parameters, that is ...

 

Hi. There are actually a few people around here that have access to the current in service technical publications for a variety of missiles (AIM-120C included), aircraft and other weapons systems. However none of us can post specific information for, what I hope, are obvious reasons.

 

You'll just have to live with what can be gained from public/semi public info that ED and people like GG have. Which i must say is plenty for a sim, especially one at FC3 fidelity. The only people who are pulling info out of thin air are those shouting about how the AMRAAM is overpowered.

 

I'll tell you this much, the AIM-120C is DCS (1.2.3 problems aside) isn't close to how capable the weapon is in reality, and nor will it ever be.

 

In time AAM modelling in DCS will get better, but there is only so much that can be done for modern missiles when the guidance systems they employ are not yet modelled, and wot be until ED can dedicate the time needed to develop an advanced guidance model.

[SkateZilla]

Wait! So you say I can rush my Hawg now head to head on a Flanker and spank him with my hissing Sidewinders? :D

 

I just pitch up, Lock and fire AGM65 at him, technique I learned on line.

Wondered why Countermeasures werent working only to look at log to find out I was being hit with AGMs.

:pilotfly:

[Eddie]

I just pitch up, Lock and fire AGM65 at him, technique I learned on line.

Wondered why Countermeasures werent working only to look at log to find out I was being hit with AGMs.

:pilotfly:

 

Yeah, I can't wait until that one is fixed.

[Arrowhead]

I read somewhere that the AIM-120 had a probability of kill of 11%. Aren't BVR weapons actually quite ineffective against maneuvering targets in real life?

[SkateZilla]

I like how people assume the AIM-120 is a 100% Hit Missile... lol... and just cuz you have a lock, and fire, doesnt mean the missile will be a 100% chance hit.

 

I shot down 3 Flankers last night in a dry run at 50nm, then shot myself down (funny actually), with my last AIM-120

[GGTharos]

No GG, don't have any problem with that ... it's just the notion that you usually declassify old technology which is not important and valid anymore. ;)

 

It is both important and valid. Look at that diagram, that's AIM-9L in normal configuration and 'AIM-120 fin' configuration (This is the 'variant'). These are not simulated measurements that are presented, but real ones. They tell us that AIM-9M should have a particular rocket performance, for example, and allow us to deduce the drag of the missile in straight flight. (Personally, having seen that rocket motors advance with each lot, I'd expect the 9M to perform about 20% better over the 9L, but that's just me).

 

They also give us a clue on the effect a certain nose and fin configuration will have.

 

There is an additional piece of detail: In-game, the sidewinder was tuned to this data.

 

Launch a sidewinder and AIM-120B/C side by side with this missile, and watch what happens.

 

Now, to give you an idea of how absurd this is, realize that the AIM-120 rocket motor is more than 3/4 of the AIM-9's weight.

 

Kinematically, MRMs are under-performing BADLY in FC3.

 

 

It all boils down to what you want to model. AIM120C is easier in that regard than any of the Russian design simply because more (not all! ;)) stuff is publicly available.

 

See above. For R-27 family, I believe that ED has some pretty solid data including some or ECCM guidance logic circuit diagrams, but I haven't seen it all. Right now, I am more interested in the rocket parameters though - at least we can sort the FM, and deal with other things later.

 

I just don't understand why did you attack me personally :( ? I think that ARH and AI is behaving more "realistically" (so there you go - all this ongoing debate about missiles is in essence talking about different "realities" - simply there are no hard data to define "realism" outside classified circles) in this patch than in 1.2.2 and if you read my post it stresses only that.

 

You don't think that 1.2.3 is improvement over 1.2.2?

 

Because I was absolutely stunned at your conclusion. Now, granted, there were some things in 1.2.2 that were un-physical (for example, 120C definitely seems to have too much thrust) but 1.2.3 made it go in the other direction (way too little thrust. It seems to turn out that the truth is almost smack down the middle).

 

I should also point out, that I concentrated my analysis on the AIM-9 and AIM-120 (and AIM-7 actually) because those were missiles that I was most familiar with, and I could learn from the fastest. The AIM-9 work for example helped out with the R-73. The AIM-120 and AIM-7 stuff should help with the R-27 and R-77 as well, though the 120 and 77 are the most difficult to tune.

 

So, no, I don't think 1.2.3 is an improvement over 1.2.2. TBH, the AI may have had their weapon employment decision making tweaked, but they're not really all that smarter. They're really not employing any tactics at all, they don't crank, they don't use drag and bags except by fortune, they don't attempt to notch your sensors, they don't fly tactical formations, etc.

[GGTharos]

You remember wrong. That's Pk for vietnam-war era AIM-7 and AIM-9's.

 

In the gulf war, the AIM-7 already had its Pk brought up to .34 or more, and that's with counting firing in poor parameters, missiles that didn't function because they were just too old, etc.

 

The AMRAAM has a Pk of ~0.59 which gets a lot bigger if you discount the missiles that were counted as a miss because you couldn't tell if they all hit the same target, and discount shots in poor parameters.

 

Basically, with AMRAAM BVR has actually started becoming more BVR, where kills with BVR missiles were usually made in WVR before (not necessary fault of the missiles, ROE's could be the culprit).

 

 

I read somewhere that the AIM-120 had a probability of kill of 11%. Aren't BVR weapons actually quite ineffective against maneuvering targets in real life?

[danilop]

...

 

You'll just have to live with what can be gained from public/semi public info that ED and people like GG have. Which i must say is plenty for a sim, especially one at FC3 fidelity.

 

...

 

Thank you Eddie for taking time to respond.

 

I'm certainly grateful for this wonderful sim and all the effort ED is putting in this title. I've bought every single ED product / title since early Flanker times. I'm very well aware of the fact that we have to live with semi-correct data when talking modern military hardware.

 

We have basically two camps here when we talk missiles: whiners and know-it-all crowd. No matter Red or Blue.

 

My position on the matter is that both whiners and know-it-all are basically wrong when we're talking missiles.

 

Not enough independent data!

 

...

 

...

 

Now, granted, there were some things in 1.2.2 that were un-physical (for example, 120C definitely seems to have too much thrust) but 1.2.3 made it go in the other direction (way too little thrust. It seems to turn out that the truth is almost smack down the middle).

 

...

 

Having too much thrust is less realistic (basically impossible physically) than having too little. That was the basis of my conclusion (about laws of physics) which stunned you.

 

I'm aware of ongoing tuning of missile performance and I never claimed to be expert on the matter. However, I have enough formal education in physics and math to clearly recognize physically impossible behavior which was evident in 1.2.2.

 

At least, all missiles now seems to behave in (physically) correct and plausible way. I don't claim that they behave to exact and "realistic", current military standards though!

 

Looking forward to 1.2.4 :)

Edited February 27, 2013 by danilop

[DD_Fenrir]

Hey Tharos, ignore the self important over-burdened-with-a-sense-of entitlement clique; the rest of us realise it's still in Beta and have the capacity to grasp what a challenge just establishing accurate parameters, let alone programming to meet them is.

 

I for one admire the ED team - it's moments like this that expose the depth and complication of not only the prototypes but the effort involved in attempting to replicate them virtually. My hats goes off to the crew and their continuing efforts.

 

A reminder to the critics; trial & error is a recognised scientific process. Guess what? The guys tried and got an error. Thats why it's called Beta TESTING. I suggest you savvy the hell up.

[Arrowhead]

You remember wrong. That's Pk for vietnam-war era AIM-7 and AIM-9's.

 

In the gulf war, the AIM-7 already had its Pk brought up to .34 or more, and that's with counting firing in poor parameters, missiles that didn't function because they were just too old, etc.

 

The AMRAAM has a Pk of ~0.59 which gets a lot bigger if you discount the missiles that were counted as a miss because you couldn't tell if they all hit the same target, and discount shots in poor parameters.

 

Basically, with AMRAAM BVR has actually started becoming more BVR, where kills with BVR missiles were usually made in WVR before (not necessary fault of the missiles, ROE's could be the culprit).

 

I found it. ;)

However, both missiles are BVR, making their actual value questionable. In fact, jamming and IFF issues mean that BVR missiles are far more likely to be used as a WVR weapon than in their intended purpose. While AIM-120 did achieve 6 BVR kills out of 13 firings, all but one were against non-maneuvering targets with no ECM and no awareness of missile. By comparing difference in Pk between maneuvering and non-maneuvering targets for AIM-9, it can be concluded that AIM-120 will achieve Pk of at most 11%; however, it is larger and heavier than AIM-9, as well as more vulnerable to countermeasures, so even that is an optimistic estimate.

 

http://defenseissues.wordpress.com/2012/12/15/aim-120d-vs-mbda-meteor/

[GGTharos]

Not enough independent data!

 

The only way to get independent data is to test fire those missiles yourself. What we do manage to get is good enough data.

 

Having too much thrust is less realistic (basically impossible physically) than having too little. That was the basis of my conclusion (about laws of physics) which stunned you.

 

No, it really isn't. And I doubt you knew this anyway, nor do I believe you could calculate it out. To realize that there is too much thrust you have to know a few things about rocket motors (in other words, the physics are fine if your rocket motor is super advanced with technology we might not have yet, but not impossible just ... not likely). I'm no expert, but I know enough to do the basic math and I have enough knowledge about how propellant is expended to make a few educated guesses and say 'this seems to fit what we know' ... or what doesn't. Sometimes, you see some surprises along the way, too.

 

And the 1.2.2 behavior of missiles should definitely be making you go 'what?' if you were basing it all on known physics.

 

At least, all missiles now seems to behave in (physically) correct and plausible way. I don't claim that they behave to exact and "realistic", current military standards though!

 

They behaved in a plausible way before, too. I bet you didn't notice, but both in 1.2.2 and 1.2.3, AIM-120C has a particular problem that other missiles do not (And it should not have it) ... but we're not talking about thrust now either. I wonder if you've caught it.

[Exorcet]

Having too much thrust is less realistic (basically impossible physically) than having too little. That was the basis of my conclusion (about laws of physics) which stunned you.

Too much and too little are exactly the same. The missiles in 1.2.2 and 1.2.3 are equally valid, but both equally inaccurate. At least for the BVR missiles.

[Eddie]

I found it. ;)

 

 

http://defenseissues.wordpress.com/2012/12/15/aim-120d-vs-mbda-meteor/

 

That is about as credible a source as Karlo Kopp.

[GGTharos]

I have no idea what happened to their math skills ... but if they actually knew how to count, they'd have told you that the Pk is 0.59 ... something like 17 shots for 10 hits ;)

 

And if you know the circumstances of the shots, you take away 2 for being launched at targets too far away, one for being practically launched into the notch, and one unconfirmed hit because of multiple missiles being guided on the same target (specifically, 2 missiles at the same time, from 2 different planes).

 

So you end up with 13 valid as far as we know shots for 10 hits ... and a Pk of 0.77. Don't quote me on the 'out of parameters shots' numbers though, I don't know them all that well.

 

I found it. ;)

 

 

http://defenseissues.wordpress.com/2012/12/15/aim-120d-vs-mbda-meteor/

Edited February 27, 2013 by GGTharos

[GGTharos]

Yep, that guy posts a lot of hogwash (picard578), I read what he wrote and I find it amusing that he considers all the targets to have been non-maneuvering and un-aware, and of course, if a target maneuvers, AMRAAM Pk will be zero.

 

That is about as credible a source as Karlo Kopp.