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

spacenavy90 · October 5, 2023, 2:11am

Two targets flying front aspect at co-altitude. I fire one AIM-54A at each of them respectively and lose the lock. Then they turn away to “fool” any inertial guidance. Then I reacquire soft-lock on each of them, alternating every second or so to continuously update guidance. Eventually both missiles score a kill. Very interesting indeed.

Now this isn’t how it works in reality, but it is interesting to know that the game logic is there. A better way to implement this (if Gaijin wanted to that is) would be to add a keybind to designate TWS targets that correspond to the missile fired (TWS target 1 = first missile fired, TWS 2 = 2nd missile, and so on).

Edit:
Same video in 1080p quality, dunno why the first exported in 720p…

MythicPi · October 5, 2023, 2:13am

Theres a good possibility they just got acquired by the 54’s own seeker there, those were rather short range launches

spacenavy90 · October 5, 2023, 2:16am

No not here, they were fired from 30 miles, datalink correction started around 25 miles. The active radar range is closer to 6-10 miles.

It isn’t in the video also but when we recorded I remember the two targets told me in voice chat they got RWR pings around 50 seconds in that video.

Also the video quality is kind of bad, but these are miles not kilometers.

Dragon_Storm_246 · October 5, 2023, 2:18am

its in Miles not Kilometers

Flame2512 · October 5, 2023, 4:39am

As I said to MiG-23M I strongly doubt that video actually shows an AIM-9M (I can’t find any information on Denmark using the AIM-9M, and similar firings are all labelled as AIM-9Ls by official sources - that video is from some random YouTube channel).

MythicPi · October 5, 2023, 4:56am

Here’s a 9X at contrail altitude, and we have multiple videos of its low smoke at lower alts as well if you still want to argue.

Low smoke/smokeless motors still produce contrails at the appropriate alts

MythicPi · October 5, 2023, 5:00am

The fact were still arguing “if” tge 54C has a reduced smoke motor, despite it being a widely documented fact jusr because some people cant figure out that contrails will occur at contrails altitudes is quite frankly simply mind boggling.

The bug reports have been accepted, the documentation was not only provided by players, but by gaijin technical moderators themselves. Its idiotic were even having this argument, nvm the fact that the devs keep dilly dallying on the subject

MythicPi · October 5, 2023, 5:09am

This is LITERALLY one of the first arguments that was had and resolved back when the 54C reduced smoke motor bug report was suggested, and was resolved MONTHS ago. At this point its just childish idiocy.

Sidenote, does anyone know if gaijin actually models rocket motor thrust increase along with decreases in atmospheric pressure? This would exxplain some underperforming on teh 54C’s speed despite lofting:

https://apps.dtic.mil/sti/citations/AD1025239

Flame2512 · October 5, 2023, 5:20am

So model contrails in game then an AIM-54C being almost invisible at high altitude (as the AIM-9M currently is) would be both ahistorical and unbalanced.

I’m not arguing that the AIM-54C doesn’t have a reduced-smoke rocket motor, just that it should not behave in the same way that the AIM-9M currently does (which is what you are arguing for with your “just change one line of code” comments).

_ShadowFang · October 5, 2023, 5:33am

Glad you were able to replicate it. Going forward people will need to know about this caveat when active missiles become the norm. Until TWS is more accurately replicated, we’ll have to use this tedious form of flight corrections.

ACOMETS · October 5, 2023, 8:17am

as the missile burns it produces H2O in form of steam , which is den condensed into condensed steam which is cloud , you can see such contrails on planes too

Flame2512 · October 5, 2023, 8:35am

I know what contrails are, that doesn’t change the fact that the video in question likely does not show an AIM-9M.

ACOMETS · October 5, 2023, 8:37am

wait , don’t you recognize the video?
it is the F-22 shooting down the Chinese balloon over the ocean with deactivated warhead few months ago

Flame2512 · October 5, 2023, 8:42am

You replied to the comment in which I was replying to this video:

Which most certainly is not the balloon video, that was posted later.

MiG_23M · October 5, 2023, 8:46am

AIM-9L also use reduced smoke motor after a certain point. The smoky motor stopped production and they are pretty far past shelf life otherwise unless they are using expired rocket motors.

MythicPi · October 5, 2023, 12:23pm

Not necessarily actually, seeing as contrails are excessive in their occurrence altitude in WT for the most part, and the vast majority of gameplay in WT occurs at lower alts. There’s also this paper, published a few months ago discussing the formation of visible contrails from rocket motors which indicate they form/become visible at altitudes between 10-15km (though the steps were in increments of 5km, and other sources such as NASA do discuss contrail formation around 8000m(26000ft), which corresponds roughly to the temperature ranges shown in the above graph I posted regarding H2O contrail formations for missiles (< -35°F).

As for HCl contrail that occurs below -10°F, roughly 6100m (20000ft) alt, that is still well above the altitude most players even bother flying at in WT atm, particularly with the massive disadvantages of flying at alt currently from the mix of H2O contrail formation being much too low, coupled with the specifics of the spotting mechanics and the absurd levels of multipath that all radar missiles suffer from, making it unadvisable to fly at altitude anymore.

So no, in most WT flight cases, barring winter maps, high alt maps, or full EC maps, Pheonix launches would actually occur below H2O contrail altitudes, and might be near/in the HCl contrail altitude, and they may climb for a momentary period of time above contrail formation altitudes, so it ISNT really that “ahistorical”. Its also not “unbalanced”, as as I’ve previously indicated, the missile diamond from the rocket motor burn (visible even on low smoke 9M’s because thats how gaijin models it) would remain visible for the totality of the 30 second burntime of the motor within 10km, while the active radar seeker would trip the RWR out at 16km. The missile would also still be visible on radar due to gaijins frankly absurd modelling of the AIM-54’s RCS. Even with a reduced smoke motor, the missile would still give you tons of warning regarding its impending impact, it would simply allow the missile to be less visually visible at range, punish players who arent paying attention while flying at altitude, and would allow closer range shots to occur in a slightly more favorable fashion.

My argument regarding this statement remains the same; if the 65D, which is closer in size to the 54C than the 9M, and has limited/no proof of actually using a low smoke motor, gets to behave the same as the 9M, there is no reason why the 54C shouldn’t pending a rework of contrails and smoke mechanics in WT. This is an unnecessary nerf to an already niche and heavily nerfed missile with hyper limited usability in WT.

MythicPi · October 6, 2023, 6:58am

Did some further testing today, and I am now convinced the AIM-54C underperforms in speed by a fair margin.

Launch conditions:

Spoiler

My speed: 1524kph (~423.33m/s)
Closure rate near launch: 1013.4m/s
Launch aircraft speed: ~588.08m/s (M2.0)
Launch aircraft altitude = ~12000m

Kinematics at max closure rate:

Spoiler

My speed = 1600kph (~444.44m/s)
Closure rate = 1748.4m/s
AIM-54C peak speed = ~1303.96m/s (M4.42)
AIM-54C dV = ~715.88m/s

These launch conditions, which are borderline ideal , still do not permit the missile to reach Mach 5.0+ speeds, and represent a paltry total missile dV of ~715.88m/s. I don’t think the missile could ever reach the in-game coded max speed of 1800m/s it has, as its still 496.04m/s (M1.68) too slow, which is around 69% of the total dV it gained.

Missile impact kinematics:

Spoiler

Closure rate = 1575m/s
Aircraft speed = 1563kph (~434.17m/s)
AIM-54C speed = 1140.83m/s (M3.87)

This is aggravated considerably at lower altitudes and lower speed launches, such as those seen in WT.

Launch conditions:

Spoiler

My speed: 1265kph (~351.39m/s)
Closure rate near launch: 655.7m/s
Launch aircraft speed: ~304.31m/s (M1.0)
Launch aircraft altitude = ~9000m

Kinematics at max closure rate:

Spoiler

My speed = 1478kph (~410.56m/s)
Closure rate = 1326.1.1m/s
AIM-54C peak speed = ~915.54m/s (M3.02)
AIM-54C dV = ~611.23m/s

Missile impact kinematics:

Spoiler

Closure rate = 1058.6m/s
Aircraft speed = 1662kph (~461.67m/s)
AIM-54C speed = 596.93m/s (M1.97)

At these speeds, the warning time between the missile going active at 16km and impact was a whopping 14 seconds (3:09 launch warning time, 3:23 impact time) while flying directly at the missile, and I was ACCELERATING from M1.38 to M1.51 at impact.

Even these tested conditions are more ideal than those seen in a regular WT air RB match. 9000m altitude M1.0 co-altitude launches against M1.1 targets that continue to accelerate directly at your missile are unheard of unless the target is actually AFK.

Pretending the AIM-54C would be in some way “unbalanced” if it was given a low smoke motor when it gives you at minimum 15 seconds of warning under effectively any launch condition seen in WT air RB is laughable @Flame2512

The missile is embarrassingly slow, it can’t pull anywhere near what it should pull, and its seeker is more than likely also underperforming seeing as its a literal copy paste of the AIM-54A’s seeker in-game.

On a comparative note, the R-27ER’s irl peak speeds are;
5km alt, ~480m/s (M1.5) launch = 1400m/s
10km alt, ~600m/s (M2.0) launch = 1600m/s
15km alt, ~600m/s (M2.03) launch = 1800m/s
According to this graph:

Spoiler

So the AIM-54C, launched from M2.0(~588.08m/s) at 12km altitude in WT will NEVER reach the top speed of the R-27ER, launched from M1.5(480m/s) at 5km altitude in real life.

This is despite;

The air density at 5000m being 2.37x higher at 5000m than at 12000m (0.73606kg/m^3 vs 0.31081kg/m^3), meaning the drag on the missile is ALSO 2.37x higher.
Rocket motor performance INCREASES with altitude, which I dont believe is modelled in-game despite it being a very simple equation:

BBCRF · October 6, 2023, 7:50am

The drag index is much higher than that of the R-27ER.Considering that the max flight range of the R-27ER is 130 km.AIM-54 With 160km

MythicPi · October 6, 2023, 8:23am

You’re just proving my point lmao.

The R-27ER, which if we’re to believe WT, is both substantially faster AND substantially less draggy than the AIM-54C, has LESS range than the AIM-54C?

Of course the R-27ER has less drag than the AIM-54, its a smaller missile (260mm vs 380mm). That still wont make up for a 2.37x increase in drag AND reduced motor performance that the R-27ER would be incurring at 5000m vs the 12000m launches I tested.

Nvm the fact that with 30 seconds of burn time vs the ER’s 8 sec, the AIM-54C suffers the effects of base drag for a shorter period of time, or that drag increases with velocity squared, which means that for the ER to acheive higher speeds, it must push through even higher levels of drag.

Theres no good reason to suggest the ER, launched from over 100m/s lower launch speed than the 54C, at an altitude where its motor doesnt work as efficiently, and the air is 2.37x denser, would outspeed the 54C by around 100m/s.

The descrepency in velocity gained by both missiles is MASSIVE.
The 54C launched (ingame) at 12000m from ~588.08m/s(M2.0) only gained ~715.88m/s, while the ER launched from substantially less optimal conditions gained 920m/s? Thats a 28.5% increase in gained velocity in favor of the ER.

Thats not even saying the ER is too fast, thats aaying the 54C is too slow. The missile is know to acheive/surpass hypersonic speeds (M5.0) irl, but doesnt even get particularly close to Mach 5.0 at near optimal conditions. Considering drag increases with velocity squared, I woulsnt be suprised if doubling the 54C’s burntime ingame from 30sec to 60 sec still wouldnt allow it to acheive Mach 5.0. I think gaijins thrust numbers for the AIM-54’s motor are inadequate for it to ever reach the high speeds its known for.

The ER has every single advantage ingame besides launch and leave capability, and even then, the 54C is such a bad missiles ingame that it doesnt actually matter. The ER outperforms it in every way but range, and the range is irrelevant considering the combat ranges in WT anyways.

BBCRF · October 6, 2023, 8:29am

even if the Cd is the same for the missiles, then due to the area of the AIM-54 midsection, it will be worse.The EP is limited to a battery life of 60 seconds. Phoenix has no such problem. It already reaches 5M speed in the 1800m/s card.Both have a dual-mode engine

The ER is still limited to a minimum G and a minimum collision velocity with the target.Perhaps the Phoenix accelerates more slowly due to this it retains its energy longer