The AIM-54 Phoenix missile - Technology, History and Performance

British players purposefully avoided nerfing certain equipment for self-serving reasons, or so I thought. What had actually happened was they were misinformed by tech moderators that it was something which could not be reported.

This situation is different, Mythic is claiming I have access to documents usable in bug reports and have decided not to share them or make a report. This simply isn’t the case and today is his first day back from a temporary ban. He feels it is necessary to stir drama and cause a scene. I suggest we all calm down and stop derailing the thread. We can instead focus on the good testing he did and work towards finding reportable discrepancies.

He is complaining about me not sharing data but allegedly had me blocked, him and all his friends. The argument was nonsense. Let’s just drop it and let staff deal with the issue.

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  1. I’m not derailing the thread, this info is relevant to the AIM-54
  2. I stated the info was alleged as I have not seen the document, but I believe others had the right to know info may be being concealed
  3. There is no rule against bringing up info from our conversation
  4. I had also specifically warned you that I intended to bring up the info that documents were being concealed a week ago

If anyone’s trying to derail the thread here, its you. I brought a bunch of new info to the thread and you got fixated solely on allegations of a document you may be concealing along with others for personal gain. The info is also not misconstrued or incorrect, I saved all screenshots of the discussion, but figured that adding them as evidence would in fact be derailing the thread.

As for Tacview, we never needed tacview to determine missile speeds, I’ve done it before, in this thread no less, (as have others specifically for bug reports) using the rate of closure from radars to determine missile speed. Tacview has just made things easier.

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This is a fantastic write up and finally tangible work in this thread instead of the previous screaming that has occured too often.

Nice.

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Thanks! I was really excited to bring this new info to the thread! I always had a feeling the missing AAT would be an issue but I was actually pretty surprised at how much of a difference it makes performance-wise.

The fact loft profiles had little impact on time to target, but a major impact on impact velocity at range was interesting.

“The Wall” was also an interesting finding and will need to be addressed by gaijin in the future. I’m really curious to know what’s actually causing it.

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You assumed the nozzle of the missile would be the diameter for both.
In both cases, we know this is not the case. Your results for AAT are thus highly skewed.

They are further skewed by the fact that you assumed the in-game thrust is for sea level conditions and that it should only increase because of “AAT”. In reality, the in-game thrust is optimized for high altitude conditions in the first place and introducing thrust changes based on atmospheric pressure would hard nerf the Phoenix at all altitudes below ~10-15km range.

All of your testing is with the assumption that the Phoenix (known to have inefficient loft profiles due to 1960’s computers and technology)… would have a superior loft profile to modern day AIM-120’s?

You had not consulted anyone here, certainly not myself (since you think I am hiding information)… about your testing methods. Instead choosing to go on a wild goose chase to test things that are not a problem in the first place. If you had unblocked me and shared your testing plan ahead of time you’d have been able to save yourself the time and effort working on non-issues.

Do you have any proof for missile thrust being modeled after high altitude conditions? I dont believe that is the case.
Also, wasnt the aim54c seeker and guidance technology developed alongside the aim120? Making it much more modern than 60s technology?

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Did you just make a new account to respond instead of just unblocking me?

Anyhow, to answer you… The AIM-54C predates the AIM-120A by a decade… The 2010+ AIM-120’s are still improving range through enhanced trajectory shaping and loft. To claim the AIM-54C should already have the most optimal trajectory is absurd.

Bruh, look at me in game. Does this look like a new account to you?
Thanks for being rude for no reason.
And my first question still remains. Cause to me this aat thing makes sense.

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Yet, sparrows M(early 80s) were improved aswell by finding a (better) optimal trajectory. Trajectory shaping is not a new concept.

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I did not say the AIM-54C (a decade newer than AIM-54A) should not have improved trajectories over the A model. I simply stated it should not have the most optimal trajectory possible in-game because it wouldn’t historically either.

Fact of the matter is, it was designed with 97,000 lb-s impulse for use against high speed high altitude bombers and the impulse would need to remain that high at approximately 10-15km alt to meet the range and performance requirements given in outsiders view as well as the conditions shown in known datapoints. If it meets these points, and it does, then considerably increasing the impulse over what it has currently is unrealistic.

Instead, the only case for increased thrust that we have currently is as a work-around for the reduction in drag during motor burn time due to the more aerodynamic thrust cone at the rear. Drag value should go up, as should the thrust. This way it reaches the proper top speed and then decelerates at the correct rate as well.

Currently this is not reportable because we do not have sufficient data.

There is no proof for that, furthermore, may I remind you that at least the climb angle is still shallow and inaccurate in the game, since historical footage clearly shows the Phoenix is climbing much more aggressively than current implementation in the game.
Even if Aim54 does not have the best trajectory possible, it should have much better trajectory than it currently has in the game (where it barely climbs after launch). Since the only proof available is Aim-54’s trajectory in the game is worse than footage had shown.

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There is a variable called endSpeed, it is used to hard cap missiles. The wall you found are these values.
War Thunder had two systems for simulating rocket/missiles. One it simply gives it an initial velocity with end velocity to prevent it from goging too fast (I don’t remember if there was an option to accelerate it without thrust), the other one was using thrust to calculate acceleration and CxK for drag (used by recent rockets and missiles). The end speed is still used as the hard cap to avoid missile flying too fast and going out of spec (IIRC, missile over speeding is a real issue, since missile diving too fast into denser atmosphere has chance to disintegrate).

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Hell, I do the same thing. For example there are many potential changes that the Sidewinder could receive, but since I can’t guarantee for example that SEAM pattern(s) are universal to all carriers (which I know there are at least two Search patterns; Con-Scan & Split D, that were developed) for a given missile variant.

There is no point in bug reporting it (yet) as it would be a novel application of an existing feature, unless Gaijin abstracted the system to increase the pre-launch FoV(an arguable Nerf, as it would slightly less the double the instantaneous Field of Regard to ?4.8? or ?4.6? degrees from the current 2.5), and could be further made by some combination of FoV reduction (IRCCM method) to mimic the true FoV after lock on, but would probably be significant work, especially considering it would additionally need to account for Sensor / HMD / Manual Slewing, and impact USN / Common Sidewinder variants from basically the F-8 / AH-1T and later airframes.

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The C improved alot of stuff and made a switch from juat bomber killing to fighters aswell. Handling stream raids, maneuverable targets, notching(MPRF/HPRF rather than just CW if I remember correctly), signal processing overall and definetly guidance algos. Having the missile loft a bit more under more circumstances to have better energy isn’t far stretched.

Currently if you fire a missile at 60km at 30kft to a target under 4kft ft the missile will just go straight for the interception point in a flat trajectory requiring higher AoA to keep the trajectory and increasing drag in the process. And at 60km you got a dead missile…

Not seeing this is just being dismissive. Having a curved trajectory will greatly benefit it.

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Presumably if two equivalent missiles with the same battery time existed, and one had improved loft, it would be said that the missile with the improved loft has increased range, yet I have not come across anything stating that the 54C obtained improved range.

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Proof for what? The fact that the AIM-54 does not (and never did) employ advanced modern guidance principles? The XAAM-N-11 was tested in 1963, the missile itself seeing very few changes before finally entering service on an airframe in 1973. The 1983 model (AIM-54C) incorporated many advancements, but would have been some of the earliest examples of the same technology seen in the AIM-120. The AIM-120 itself having had quite a few iterations that incorporated more advanced guidance methodology.

Not only do we not need proof, it is totally unreasonable to assume the Phoenix had optimized lofting trajectories. Yes… we know it isn’t correct in-game and there is room for improvement. We should not jump from the current loft mechanism to the most ideal one possible though.

Yes, that is what I said and you appear to have disagreed and then re-stated what I was saying.

The AIM-54A was already fully capable of killing fighters.

There is nothing to suggest it has MPRF guidance, but it is likely. There is a new motor, new seeker, new guidance unit… it may very well be a massive jump but we don’t have the data to make such assumptions of performance increase.

I never said that the in-game trajectory and whatnot was accurate.

This is logical.

Outsider’s view states a 97,000 lb-s total impulse. For a 25 second burn time this would be a total of 3,880 pounds thrust over 25 seconds. Divide 97,000 pounds by the 30 second burn time we have in-game and you get the total 3,230 pound-force… as seen in-game.

If you want higher thrust, you will get less burn time. The overall performance will be identical based on altitude in regards to overall impulse of the motor. The acceleration will be improved both from reduced drag and higher thrust but the motor doesn’t magically gain total impulse from AAT.

We also know his attempts to calculate the proper AAT are off by quite a long shot. The motor of the AIM-54 is not some secret, we know the size of the nozzle is not more than 9.xx inches based on the diameter of the missile body and the motor nozzle itself being visible.

The in-game thrust is 3,226 lb-f which is accurate. The total impulse given in the various sources available divided by the burn time give us correct thrust. This is for high altitude scenarios because that’s what the requirement for the motor was for.

You are assuming the exhaust of the rocket motor matches the diameter of the missile and this is not the case. This will drastically affect your math and it needs to be re-done. The diameter of the AIM-120’s nozzle can be considered closer to the diameter of the body than what is given on the AIM-54 based on photos. Stop pretending you aren’t reading what I’m saying so we can have a productive conversation.

That’s my bad, I’m sorry.

Originally I wasn’t gonna bother with this thread but I’m glad you admitted where you got your “information” from.

First off, is Mig23M credible or no? You’ve always insinuated Mig23M isn’t to be believed but now apparently you modeled a missile based on some hearsay from Mig23M thru me.

Second, the whole write up, all of the work you did, and the missile modeling is useless for several reasons:

  1. I read a cropped chart with little to no context incorrectly.
  2. The chart requires perfect measurement to accurately read it, I spitballed the figures while also reading it incorrectly (see #1).
  3. The missile possibly was a lighter earlier variant without a seeker, hence the no loft, I didn’t clarify thru Mig23M because I didn’t care too much.
  4. Mig23M isn’t trustworthy (joke)

Forecast also isn’t a good source to determine the maximum range of the radar. Gaijin does not even accept them as a source as it’s considered to be Jane’s.

You need to come to terms with whether or not Mig23M is to be believed or not. You cannot cherry-pick and say he’s untrustworthy and then switch up the next minute and model a missile based on some “document” from Mig23M that you do not know if it exists. I also had told you I myself did not have the document.

Anyway, this is the last I’ll say of anything on this topic. But it’s clear, Mig23M as well as tech mods should be believed over anything you have to offer.