I do wonder if it’s somehow possible to extract missile altitude from the replay file itself. Unfortunately I’m nowhere near knowledgeable enough about the game’s code to even begin figuring that out myself, though someone else may be.
I think that so long as the the loft reaches the altitude, and that the missile is fast enough to travel 72.5 nautical miles in the test scenario before striking the target, then the modeling of the missile should be good enough.
I dont bug report anymore. I barely bother pinging mods anymore seeing as stuff like today happens where gunjob didnt really bother reading or understanding my question, and K_stepanovich completely ignored the question despite answering a different question of mine on another thread.
Gaijin will ignore any and all sources and evidence so long as it doesnt fit in their world view.
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This is a completely out there suggestion, but wouls it be possible to make a user model “plane” using the AIM-54 and just “fly” it? You could at the very least see if the missile can even reach the required altitude on 30 seconds of motor brun from the expected launch condition
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These issues aren’t mutually exclusive, but I want to hedge bets that excessive drag compounds lofting issues. That, plus the targetOmega could help alleviate some issues. The reason I’m hung up on drag is that it progessively gets worse as speed increases, which almost certainly affects it adversely in any stage, modified lofting or not.
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Terminology is perfectly fine, the AMRAAM enhanced the maximum ballistic range solely with trajectory shaping. AIM-54 being much older, and with far less complicated guidance systems can’t possibly achieve a peak efficiency loft. It simply doesn’t have the necessary sensors and hardware.
As Direct support has shown, loft is fine. Missile drag is far too high. I’ve already explained this.
The thing is, i have no idea how to prove drag is too high, nor do I really know where the claim comes from. The CkX for the AIM-54 is alreadybinsanely low in-game, which is why i have my doubts about it being a drag issue, since afaik, it has the lowest drag coefficient im-game for any missiles. (Granted I understand we arent clear on exactly how CkX works)
I think its a lot more likely to be a loft profile issue. Everytime loft has been improved (old loft code → current loft code → dark_claw imrpoved loft code) the missile has made somewhat substantial jumps in performance.
The AIM-54 is a large missile, with a large motor area, and a long burntime, literally all factors which would dictate it would love to be at high altitudes for as long as possible. NASA prelim sims for the ALSM also piint in the direction that simply improving loft angle for the missile significantly improves performance, particularly at range.
Hell, legoCubes test, which literally only modified omegaMax, saw a 20%+ improvement in impact velocity. Clearly the AIM-54 benefits greatly from being at higher altitudes faster/for longer. Much more so than I believe most of us realized.
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My best guess is the lack of modelling of drag reduction from the motor’s exhaust gasses while its burning (is there a shorthand term for this?). Other missiles can get away with ignoring it or tweaking the thrust values to compensate as most of them have comparatively short burn times, but Phoenix with its 30 second burn is likely affected disproportionately more.
It would be base drag reduction from motor brun iirc. Could also just shorten it to the basebleed effect I guess, since thats what basebleed shells use to enhamce range.
Thats only 1 part of the equation though. As Ive posted many times here before, rocket motor impulse increases dramatically with altitude, something I dont believe is modelled in-game.
Also, like Ive previously stated, do we have any actual proof the AIM-54 has too much drag? Ive never seen anything detailing actual speeds acheived for a given missile shot.
Best ive seen are:
- the inaccurate NASA sim (used publicly available info only)
- multiple claims of a top speed of M5.0 (doesnt help a whole lot when we dont know under what launch conditions)
- A claim I posted at one point from an alleged AIM-54 test engineer (claimed M6.1 at some point iirc?) But despite that alleged engineer having some fantastically obscure info which lead to finding details about the WGU-29/B being a directional warhead, im still not sure if he is who he claims to be, and never got a further answer from him.
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The earlier source you provided has the necessary detail to model this. After the AIM-54 Phoenix reaches the peak altitude stated in the launch conditions given, it travels 72.5 nautical miles before killing the target.
If it ends up traveling less than 72.5 nautical miles before killing the target, then it is too slow.
The missile arrives after 72.5 nautical miles of travel as the target moves at the speed of Mach 1.5.
Top speed is mach 6.1 from ~2+ mach launch
The source I posted doesnt include what kind of energy state or time it took for the missile to impact the target. Nor does it specify if 72.5nmi is horizontal range, slant range, or total trajectory range. It doesn include trajectory nor does it include impact angle.
In theory it could be used to test if the missile can acheive one permutation of this multivariable problem, but it doesnt garantee said permutation is correct.
Also, you could probably test the loft profile to some degree by either firing the AIM-54 modified to be unguided at a 15° angle and seeing how high it reaches, or maybe by adapting a lower speed target to reach the apparopirate impact point at the required moment, which would mitigate your need for a M1.5 50kft target and 110nmi of range
IIRC the radar render range limit only applies in multiplayer, there is no limit in user missions.
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I read it, there just isn’t alot I can say on the matter as I don’t make the decision when something is or isn’t changed. I can only feedback what the devs tell me and if there is no report for it I have no feedback and nothing to give.
Should be horizontal range. When you do the math, the missile impacts at ~160seconds, the limit of guidance. It’s limited to battery imo.
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Sorry for misunderstanding then, but your reply was literally that loft code was “new and in test”, which is both untrue, and leaves most of my post unaccounted for and unanswered, which is why I figured you didnt bother reading or understanding it.
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Where did you get ~160 seconds for impact? Did you just do a basic trajectory calc? Also, I would’ve guessed slant range, seeing as the 110nmi is given in slant range, but my second guess would’ve been 72.5nmi along the missile trajectory, since it was referred to as “missile flight”
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Also, anecdotal evidence, but I think this is the only shot I’ve seen where we get a glimpse at how aggressive the AIM-54’s loft is (the video is also just a fun watch so I’d give it a look just for the enjoyment factor too):
Edit:
Found more footage of a lofting AIM-54, this time a side view of an AIM-54A:
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I mean in its new more aggressive form that is new. Sorry I’ve never really had a deep dive into the existing lofting mechanics.
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Its new for air to air missiles I guess, but the ground attack munitions have been lofting this aggressively and more so for a long time as well.
Idk, maybe I’m being too harsh, but as it stands, particularly since we know gaijin has the sources for 25g maneuverability but isn’t acting on them (I could dig up all the times David_Bowie has brought sources up and spoken about it), and the loft profile of the AIM-54 has already been arbitrarily improved once, and the most recent near doubling of fin AOA, it seems more and more like the control profile of the AIM-54 is either being completely guessed at and/or intentionally held back.
I see no logical reasons for, at very least the C, not to get improved lofting and/or energy management code like all other radar missiles from 1970 and beyond seen in-game. This would likely explain why the AIM-54C is quoted as being a faster missile than the A despite using similar motors and the A being lighter. We outright know that the AIM-54C got a new WGU-11/B guidance and WCU-7/B control section, so its not exactly a stretch to say the 54C would have an improved flight profile, yet in-game the only thing it improves on over the AIM-54A, which is over 20 years older than it, is a better inertial nav, leaving the AIM-54C to be outright worse in-game to its earlier A variant, for no logical or apparent reason.
That’s something I want to point out as well for those saying the AIM-54 is an “old missile”. The 54A is old, the 54C has just about every part of it changed compared to the A.
It has a new digital guidance section (WGU-11/B), it has a new directional warhead (WDU-29/B) in a new warhead section with a new fuse (DSU-28/B), a new motor (Mk47 mod 1), with a new control section (WCU-7/B).
It was being developed around the same time as the AIM-120, with the AIM-54C’s first flight test in 1980, a year before the AMRAAM. The 54C and 120A are very much from the same development time period, with the 54C likely only entering service earlier than the 120A because the 54C was an iteration of an older missile, while the 120A was brand new. Both would have had access to largely the same technologies, with both missiles being developed by Hughes during the same time period.
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