AWG-9 velocity gating?

[Naquaii]

45 minutes ago, Harlikwin said:

 

Well I agree with you on many parts of what you say, I'm just trying to apply some logic to the situation. 

 

For a late model 80's era Aim-7m seeker which were used in combat the pK was something like 50% or bit higher IIRC. Now of course theres a bunch variables there on why they hit or didn't. But lets say its being guided by a powerful (relative to a phoneix radar) with excellent performance (I.e. lets say for the sake of argument the APG63 is a better radar) at not much further ranges (20nm vs 10nm for the phoenix). So should we assume that in that same set of circumstances that the phoenix A would do better, and if so why? I realize its not entirely apples to apples but I'm really trying to wrap my head around why the phoenixA would be better in that set of circumstances strictly from a guidance standpoint? Cuz  as I see it, its got a way less powerfull radar to illuminate the target, and assuming it even has a monopulse seeker (don't know if it does one way or another, they weren't fitted to Aim-7s till much later). Its guidance logic and guidance laws are also likely going to be less refined than missile seeker built 20+ years later. 

 

As for better ECM, well, supposedly its coming right?

 

 

 

Comparing a figher radar guiding a SARH missile to an ARH missile with it's own built in radar is not that straight forward as it might seem at first. The radar equation in regards to returned power has both the range from the transmitter to the target and the range from the target to receiver squared. This means that effect of the distance from the fighter to the missile isn't just a linear advantage in favor of the ARH missile but it's squared, in addition in an ARH missile both ranges will decrease as the missile approaches the target while with a SARH missile likely only the range from target to receiver will decrease. Or at least the range from the transmitter to the receiver will not decrease as much. This means that the fighter radar guiding the SARH missile will have to have a transmitter much more powerful than the missile to even have a received power even to the ARH missile's. Adding to that the AIM-54 has a twíce as large seeker antenna which give it an advantage over the AIM-7 even in the SARH case.

 

It is true though that the AIM-7M seeker is much newer than the AIM-54A age-wise but to hold that as an advantage we'd need to know in what ways it is better than the AIM-54A and in which situations it holds an advantage. I'd wager a guess that the advantage is little in a non-jammed advantage while it will probably be greater when in a heavy ECM environment. But as to how much anyone's guess is equally as good as long as we're only able to discuss non classified information.

 

Added to that an opponent is much more likely to have seen the STT mode of a fighter radar and been able to design ways to counter that than a missile that they've never seen used against them and thus never seen the radar of in action and how it behaves.

 

The tl:dr, at least for me, is that in regards to power a SARH missile will always be a step behind and even in the SARH case the much larger antenna in the AIM-54 is a massive advantage, esp coupled with the powerful AWG-9. The ECM and ECCM/logic discussion is kinda moot as any representation will be guesswork at best.

[Skysurfer]

1 hour ago, dundun92 said:

One thing to note with the sparrow numbers is that a lot of misses were due to motor issues, e.g, motor not lighting, or the sparrow getting hung on the Pylon. IK thats all included in Pk, but it should be noted that a  lot of the misses were not due to the seeker/guidance/tracking.

 

Also, even considering all that, im not sure why people are so hung up on Pk. There are simply too many variables for Pk to really be of any use unless you have the specifics of every engagement. For example, if your trying to run a CAP and you simply need to keep the bad guys away, not kill them, you may take longer ranged, lower Pk posturing shots. While the Pk achieved in this scenario may be close to 0%, it doesn't mean the missile is bad; all it means is that the bandit defended well, and that the missiles did their job of keeping people away. The point is, saying "The sparrow had 50% Pk in combat" is fine, but its not something you can use to say "why would the AIM-54 do better". Unless you can prove that the 50% Pk was actually due to seeker/guidance/tracking issues, and that these same weaknesses were present in the AIM-54, theres no real basis for comparison.

 

[Noctrach]

I'm also going to hazard a guess that if you tally all the AIM-54A's launched online and compare to the actual kills, you'd reach a number that is significantly lower than 50% and rather much lower than the AIM-120B/C.

[captain_dalan]

Heck, even my own hit ratio can drop to 1:16 at times, and i'm far from being the worst Turkey driver out there

[Harlikwin]

58 minutes ago, Noctrach said:

I'm also going to hazard a guess that if you tally all the AIM-54A's launched online and compare to the actual kills, you'd reach a number that is significantly lower than 50% and rather much lower than the AIM-120B/C.

 

Yeah, thats totally fair. IDK, for the A it seems to me that once it pitbulls on you it should be a bit easier to spoof than say a late model sparrow based on my arguments above. IDK, just my 2 cents.

 

[Harlikwin]

2 hours ago, Naquaii said:

 

Comparing a figher radar guiding a SARH missile to an ARH missile with it's own built in radar is not that straight forward as it might seem at first. The radar equation in regards to returned power has both the range from the transmitter to the target and the range from the target to receiver squared. This means that effect of the distance from the fighter to the missile isn't just a linear advantage in favor of the ARH missile but it's squared, in addition in an ARH missile both ranges will decrease as the missile approaches the target while with a SARH missile likely only the range from target to receiver will decrease. Or at least the range from the transmitter to the receiver will not decrease as much. This means that the fighter radar guiding the SARH missile will have to have a transmitter much more powerful than the missile to even have a received power even to the ARH missile's. Adding to that the AIM-54 has a twíce as large seeker antenna which give it an advantage over the AIM-7 even in the SARH case.

 

It is true though that the AIM-7M seeker is much newer than the AIM-54A age-wise but to hold that as an advantage we'd need to know in what ways it is better than the AIM-54A and in which situations it holds an advantage. I'd wager a guess that the advantage is little in a non-jammed advantage while it will probably be greater when in a heavy ECM environment. But as to how much anyone's guess is equally as good as long as we're only able to discuss non classified information.

 

Added to that an opponent is much more likely to have seen the STT mode of a fighter radar and been able to design ways to counter that than a missile that they've never seen used against them and thus never seen the radar of in action and how it behaves.

 

The tl:dr, at least for me, is that in regards to power a SARH missile will always be a step behind and even in the SARH case the much larger antenna in the AIM-54 is a massive advantage, esp coupled with the powerful AWG-9. The ECM and ECCM/logic discussion is kinda moot as any representation will be guesswork at best.

 

I'm familiar with the radar equation and very much get R^2, that being said I don't know the actual output power of a phoenix missile radar but I do have some idea of APG-63's output power. But if you have that number its a comparison that can be made and the math done. And yes, a bigger antenna is better from a seeker and transmitter POV, but a fighter sized antenna is still king in that regard.

 

I'd certainly agree to a point about the STT thing, but basically every fighter radar has WARM modes (War reserve modes) that will have extra frequencies/pulse patterns power output and so forth for Exactly the reason you posted. The mig25 even had a secondary radar built in just for that purpose. So really, I'm not sure how relevant it is, and everyone has spies. Plus I'm pretty sure the soviets had at least a look at the Iranian missiles post revoultion at some point. 

 

Talking about ECM, really, the issue there is that the Aim54 has a pretty small "brain" compared to say a APG-63 which was fitted with fairly sophisticated ECCM, so its gonna be far harder to spoof IMO, unless you are just talking pure noise jamming, in which case both can do HOJ.  

Edited March 18, 2021 by Harlikwin

[Lurker]

On 3/14/2021 at 7:34 PM, Noctrach said:

@NaquaiiDid some more testing today, I can conclude that the following is true:
The AWG-9 loses PD-STT lock if the sum of your bank angle and ATA exceeds 55

 

So in level flight:

Banking more than 55 degrees with a target directly on the nose (ATA ~0) will break the lock.

Banking more than 25 degrees with a target at ATA 30 will also break the lock.

Banking of any kind with a target at ATA 55 will ofc also break the lock.

 

Any STT guided missile in the air is trashed because the track is considered broken the second the AWG-9 loses the lock.

The AWG-9 will remain in trackhold for 2 minutes when this happens unless manually forced out of it.

Reducing the sum to below 55 within 4 seconds will instantly regain the lock, resulting in two overlapping tracks (broken trackhold + new track from regained STT lock).

 

This issue is reproducible 100% of the time.

 

I understand we're dealing with old tech without a roll gimbal, but this math doesn't check out at all.

Rolling in level flight should translate some of the azimuth onto the elevation gimbal, rather than the other way around.

 

 

 

Noctrach I really think you should open up an "official" bug topic in the bug section forums. Just so this doesn't get lost in all the "noise" this bug is a pretty big deal if indeed it is a bug. 

Edited March 19, 2021 by Lurker

[Naquaii]

17 hours ago, Harlikwin said:

 

I'm familiar with the radar equation and very much get R^2, that being said I don't know the actual output power of a phoenix missile radar but I do have some idea of APG-63's output power. But if you have that number its a comparison that can be made and the math done. And yes, a bigger antenna is better from a seeker and transmitter POV, but a fighter sized antenna is still king in that regard.

 

I'd certainly agree to a point about the STT thing, but basically every fighter radar has WARM modes (War reserve modes) that will have extra frequencies/pulse patterns power output and so forth for Exactly the reason you posted. The mig25 even had a secondary radar built in just for that purpose. So really, I'm not sure how relevant it is, and everyone has spies. Plus I'm pretty sure the soviets had at least a look at the Iranian missiles post revoultion at some point. 

 

Talking about ECM, really, the issue there is that the Aim54 has a pretty small "brain" compared to say a APG-63 which was fitted with fairly sophisticated ECCM, so its gonna be far harder to spoof IMO, unless you are just talking pure noise jamming, in which case both can do HOJ.  

 

 

Even if the increased range from the transmitter in the SARH case and the fact that the AIM-54 has an antenna more than twice the size of the AIM-7 didn't tend towards favouring the ARH missile you still need to remember that the AIM-54 can fallback to guidance from the AWG-9 even in the ARH mode and the AWG-9 is ofc known for being one of, if not, the most powerful fighter radars out there (in regards to pure power), even to this day.

 

Discussing seeker logic and ECCM performance is really a moot point as you'll never find unclassified data on that. Would be AIM-7M be more advanced than the AIM-54A? Very likely. But in what situations and what cases would that give the AIM-7M an advantage? And could we even model that in DCS?

 

In any case, discussing opinions and feelings isn't really leading anywhere and to make us change our stance and modelling of the AIM-54 we'd need proof and we already have information supporting how we've modelled it currently. I still haven't seen anything approaching proof of the AIM-54A being anything but a decent/good missile against fighters.

[Noctrach]

@Naquaii In response to some of the questions, I know you're already checking so would you prefer to leave the STT issue in this (very interesting) thread or shall I crosspost it to the bugs forum?

[Harlikwin]

2 hours ago, Naquaii said:

 

Even if the increased range from the transmitter in the SARH case and the fact that the AIM-54 has an antenna more than twice the size of the AIM-7 didn't tend towards favouring the ARH missile you still need to remember that the AIM-54 can fallback to guidance from the AWG-9 even in the ARH mode and the AWG-9 is ofc known for being one of, if not, the most powerful fighter radars out there (in regards to pure power), even to this day.

 

Discussing seeker logic and ECCM performance is really a moot point as you'll never find unclassified data on that. Would be AIM-7M be more advanced than the AIM-54A? Very likely. But in what situations and what cases would that give the AIM-7M an advantage? And could we even model that in DCS?

 

In any case, discussing opinions and feelings isn't really leading anywhere and to make us change our stance and modelling of the AIM-54 we'd need proof and we already have information supporting how we've modelled it currently. I still haven't seen anything approaching proof of the AIM-54A being anything but a decent/good missile against fighters.

 

Well the two main points I have on that, and perhaps you have more info on this.

 

Notch gate performance of the phoenix, as its generally gonna be looking down when falling at targets from space. Given the "A" is the same era as the AWG 9 I think the A should be straightforward to notch. Though as you say if it is still supported, that should be factored in for re-acq. 

 

ECCM/CM performance should be inferior to the 7m, maybe on par with the H or something like that in the current version of DCS. I'm not sure what the value is currently set at relative to those missiles. 

Edited March 19, 2021 by Harlikwin

[Victory205]

You are all guessing, speculating and making non-sequiturs in an environment in which you will never have access to the truth.

[Naquaii]

2 hours ago, Noctrach said:

@Naquaii In response to some of the questions, I know you're already checking so would you prefer to leave the STT issue in this (very interesting) thread or shall I crosspost it to the bugs forum?

 

We'll be looking at this as soon as we have the time, no need for another post even if that's generally where they should be.

 

41 minutes ago, Harlikwin said:

 

Well the two main points I have on that, and perhaps you have more info on this.

 

Notch gate performance of the phoenix, as its generally gonna be looking down when falling at targets from space. Given the "A" is the same era as the AWG 9 I think the A should be straightforward to notch. Though as you say if it is still supported, that should be factored in for re-acq. 

 

ECCM/CM performance should be inferior to the 7m, maybe on par with the H or something like that in the current version of DCS. I'm not sure what the value is currently set at relative to those missiles. 

 

 

If you ever get any solid info on this, feel free to share.

[AH_Solid_Snake]

1 hour ago, Victory205 said:

You are all guessing, speculating and making non-sequiturs in an environment in which you will never have access to the truth.

I assume you’re referring to the guesswork regarding SARH vs ARH and all the various speculation on the Phoenix? Or did you mean the original discussion around the AWG-9 is not a bug/expected behaviour?

[Looney]

I would say the first, SARH/ARH radar modes, jamming and all that sorts.

 

The main question the OP asked, the sum of ATA and bank angle > 55 = loss of lock, is still open and we're awaiting HB response on the matter.

[Harlikwin]

1 hour ago, AH_Solid_Snake said:

I assume you’re referring to the guesswork regarding SARH vs ARH and all the various speculation on the Phoenix? Or did you mean the original discussion around the AWG-9 is not a bug/expected behaviour?

 

Probably all that phoenix stuff, plus he knows that the phoenix actually had an IR terminal seeker (which explains why its chaff resistance and unnotchability)... And I'll stop derailing the thread, it wasn't my original intent, it just spiraled that way.

 

Edited March 19, 2021 by Harlikwin

[Gunslinger22]

45 minutes ago, Harlikwin said:

 

Probably all that phoenix stuff, plus he knows that the phoenix actually had an IR terminal seeker (which explains why its chaff resistance and unnotchability)... And I'll stop derailing the thread, it wasn't my original intent, it just spiraled that way.

 

 

Where else have I read this! It might have even been a Tom Clancy book, but it’s not the first time someone has whispered the holy words of the Phoenix having a terminal IR seeker! Heck I don’t know how Clancy got so much details on the 688 right, but not sure if he’s to be trusted as much with things like NAVAIR. 

[Noctrach]

1 hour ago, Harlikwin said:

 

Probably all that phoenix stuff, plus he knows that the phoenix actually had an IR terminal seeker (which explains why its chaff resistance and unnotchability)... And I'll stop derailing the thread, it wasn't my original intent, it just spiraled that way.

 

 

Ehhh, I don't mind the discussion as it turns up interesting info from various sources, but if it devolves into a "continuously bash Phoenix based on headcanon and poor notching skills" I'll ask HB to lock it down until they finish their investigation.

 

Considering Victory205 was trained to employ the missile, while the rest of us have never even seen a real one, I'm generally inclined to take his insight over pretty much anyone else.

 

Besides, taking into account the mere existence of clouds and hot summer days, I think an IR terminal seeker would've mostly been an operational downgrade.

Edited March 19, 2021 by Noctrach

[Harlikwin]

1 hour ago, Noctrach said:

Ehhh, I don't mind the discussion as it turns up interesting info from various sources, but if it devolves into a "continuously bash Phoenix based on headcanon and poor notching skills" I'll ask HB to lock it down until they finish their investigation.

 

Considering Victory205 was trained to employ the missile, while the rest of us have never even seen a real one, I'm generally inclined to take his insight over pretty much anyone else.

 

Besides, taking into account the mere existence of clouds and hot summer days, I think an IR terminal seeker would've mostly been an operational downgrade.

 

 

LOL, now Clancy... I meant it more as a semi joke, largely because IR tech of the day in theory could have made a vastly better seeker than what was stuffed into the cheap-ass sidewinders of the era, it just would have been spendy and needed some "bulk" both of which the phoenix had, and there is ton of precedence for, put the missile in the "area" point it the right way, let the terminal seeker do the rest. Turns out one can do alot with the old-school tech, in fact I'm building a "replica" of a mig29 IRST in my garage, I just happen to have an arudino to process to it, which well, is handy.... maybe I'll report on how well it can detect cessnas from the local airfield :).  On that note, I've never seen an actual nosecone off pic of a phoneix, cuz that would clear that up that misconception "quickly". And yes IR seekers have plenty of their own limitations (hopefully modeled in DCS coming soon (tm)). And I have seen a phoenix up close (in a museum).

 

What I do know, is that monopulse seekers existed before they were implemented in the AIM7 series (skylflash in the mid70s), the russians used them on the R23/R24 series in the early 70's, a big part of that was miniaturization of electronics. So its plausible that the Aim-54 did too (again, an antenna pic would clear that up quick), it was certainly big enough. I do know the missile that the phoenix was developed from absolutely didn't use such a seeker, and I know what is known about it, and well, while "cool" I doubt how "effective" it would have been specifically in look down (not good), but it was built for look up scenarios, so that offers some clues. But engineering also moves on. 

 

As for Victory, (whom I totally respect as a veteran and an aviator btw)..  Well, best I will say is that they guys going to VN would have said EXACTLY what he said about the early model sparrows and sidewinders that they were trained to employ prior to going to VN based on "the best testing the Navy or Air force could provide". Literally never has a US soldier gone to war without full faith in his equipment, right or wrong (and frankly the whole VN experience shook up the whole mil/industrial/congresscritter complex). That being said, I'm pretty sure guys like Randy Cunningham and Robin Olds had some other things to say after they actually started using those "highly reliable" missiles in combat. Sadly, the absolute best metric we have for how effective they were is the 0/3 record of the USN, and then the unfortunately "spotty" (is that a nice enough word?) of the IRAF aces, which does somewhat backup Victory, but there are various congressional hearings that "sound" a little skeptical of the A model as well. So bottom line here is that I DO think, the A model can kill a "mig23 (BN or whatever)" when it has no u useful RWR to let it know its under attack, i.e. when it has no clue as to the threat its facing and so forth (and this is a very large part of war/reality at any given time). Using an 70's era A model phoenix against a 2000's era opponet with a modern RWR and ECM... Well... That's a different story IMO. 

 

To that end, I have read that report that HB based their model on, and well, frankly, I found some of those tests that were (not counted as failures) to frankly be failures, which IMO is typical of the era and the mil-industrial complex of the time, and it lowered my opinion of the missile. Also, IIRC there were no long range engagements of maneuvering targets in that report, just the one short range engagement against the maneuvering drone, and nothing "notching" as far as I recall. I think the ultimate point is that if the A was so great against fighters, why was the C specifically designed to be "better" against fighters?

 

Edited March 20, 2021 by Harlikwin

[Gunslinger22]

13 minutes ago, Harlikwin said:

 

LOL, now Clancy... I meant it more as a semi joke, largely because IR tech of the day in theory could have made a vastly better seeker than what was stuffed into the cheap-ass sidewinders of the era, it just would have been spendy and needed some "bulk" both of which the phoenix had, and there is ton of precedence for, put the missile in the "area" point it the right way, let the terminal seeker do the rest. Turns out one can do alot with the old-school tech, in fact I'm building a "replica" of a mig29 IRST in my garage, I just happen to have an arudino to process to it, which well, is handy.... maybe I'll report on how well it can detect cessnas from the local airfield :).  On that note, I've never seen an actual nosecone off pic of a phoneix, cuz that would clear that up that misconception "quickly". And yes IR seekers have plenty of their own limitations (hopefully modeled in DCS coming soon (tm))

 

What I do know, is that monopulse seekers existed before they were implemented in the AIM7 series (skylflash in the mid70s), the russians used them on the R23/R24 series in the early 70's, a big part of that was miniaturization of electronics. So its plausible that the Aim-54 did too (again, an antenna pic would clear that up quick), it was certainly big enough. I do know the missile that the phoenix was developed from absolutely didn't use such a seeker, and I know what is known about it, and well, while "cool" I doubt how "effective" it would have been specifically in look down (not good), but it was built for look up scenarios, so that offers some clues. But engineering also moves on. 

 

 

 

 

 

 

 

 

 

Oh trust me, not for a second do I actually think the 54 had some special IR seeker, I just find it amazing that I have read or heard someone bring it up before, because what a unicorn that would be haha! 

[Harlikwin]

21 minutes ago, Gunslinger22 said:

Oh trust me, not for a second do I actually think the 54 had some special IR seeker, I just find it amazing that I have read or heard someone bring it up before, because what a unicorn that would be haha! 

 

LOL, well, I had no idea that Clancy said that so there is your Unicorn. Though given the sensor tech of the day it could have been done, in fact in the late 80's and early 90's the THADD ABM system basically used that same exact scheme I describe. They blew off the aerocover of the missile once it was near the target to expose the IR seeker. And cooling was a serious challenge. So it made me think of the cooling problems of the phoenix. IDK, maybe Clancy was right...

 

 

 

Edited March 20, 2021 by Harlikwin

[Naquaii]

11 hours ago, Harlikwin said:

To that end, I have read that report that HB based their model on, and well, frankly, I found some of those tests that were (not counted as failures) to frankly be failures, which IMO is typical of the era and the mil-industrial complex of the time, and it lowered my opinion of the missile. Also, IIRC there were no long range engagements of maneuvering targets in that report, just the one short range engagement against the maneuvering drone, and nothing "notching" as far as I recall. I think the ultimate point is that if the A was so great against fighters, why was the C specifically designed to be "better" against fighters?

 

Please do tell, you must know something about what "reports" we based our missiles on that I do not.

[Harlikwin]

2 hours ago, Naquaii said:

 

Please do tell, you must know something about what "reports" we based our missiles on that I do not.

 

I think the most pertinent part was the following:  there were no long range engagements of maneuvering targets in that report, just the one short range engagement against the maneuvering drone, and nothing "notching" as far as I recall. I don't happen to have it sitting in front of me though. 

Edited March 20, 2021 by Harlikwin

[Naquaii]

Just now, Harlikwin said:

 

I think the most pertinent part was the following:  there were no long range engagements of maneuvering targets in that report, just the one short range engagement against the maneuvering drone, and nothing "notching" as far as I recall. I don't happen to have it sitting in front of me though. 

 

 

What I was getting at was the fact that you said we based our missiles on that report. I would like to know how you know that? It isn't true. It's ofc an influence but not a majority influence.

[Harlikwin]

53 minutes ago, Naquaii said:

 

What I was getting at was the fact that you said we based our missiles on that report. I would like to know how you know that? It isn't true. It's ofc an influence but not a majority influence.

 

Well, assumption on my part since this is what you cited in your own white paper. Id be curious about the other majority sources you used?

 

[Naquaii]

Just now, Harlikwin said:

 

Well, assumption on my part since this is what you cited in your own white paper. Id be curious about the other majority sources you used?

 

 

Yes, and you'll will note that the whitepaper focuses on aerodynamics and flight performance, not guidance or seeker logic.