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

Machinery of War Discussion Aircraft
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The AIM-54A uses Ammonium Perchlorate (Flexadyne), which can have an ISP ranging from 180-260s.
The HTPB in the AIM-120 has an ISP around ~245-255, (based on this report about reduced smoke propellants).

It is possible that the HTPB matches or improves on the ISP of the original motors, and is the only reduced smoke propellant type the US used prior to the late 1990s to my knowledge. 245 / 260 = 0.942
So we are looking at the absolute most difference, 5.8% worse specific impulse. This is assuming the Flexadyne has the highest ISP (260) and HTPB has the lowest possible (~245).

TL;DR AIM-54C may have worse performance than the earlier models due to a reduced smoke motor but should only (at most) be 5.8% less ISP.

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Anyone have that image of the AIM-54 flight trajectory vs long/short range targets that was posted on the old forums? its not there anymore

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Can you describe the scenario better? I probably have it somewhere but I don’t know which one you want.

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I more specifically want the image that showed the AIM-54 had a post launch climb period before it began SARH guidance. The image has all the guidance steps an AIM-54 took from launch until hitting a distant target, and also described the 2 target scenarios (long or short range) at the bottom?

This bit here:

image
image1326×653 107 KB

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Interavia World Review of Aviation, Astronautics, Avionics Vol.37
https://cdn.discordapp.com/attachments/955829235493273680/1121576087026143283/image_1.png

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Thanks!

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According to Solid Propulsion Enabling Technologies and Milestones
for Navy Air-launched Tactical Missiles

The AIM-54A has 364 pounds of Flexadyne propellant, yet in-game the empty mass is 375 pounds less than when the burn starts. Also, it states the Mk60 is “functionally” a CTPB equivalent of the Flexadyne Mk47 based motors for the AIM-54A.
https://cdn.discordapp.com/attachments/1078877088087552102/1121631438073245747/image.png
https://cdn.discordapp.com/attachments/1078877088087552102/1121628905518931988/image.png

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@MiG_23M

F-14 WSC can change radar target size, which will also send a message to the Phoenix when to go active. In DCS the ranges are documented as: SMALL - 6 NM, NORM - 10 NM and LARGE - 13 NM.

The LARGE is 24 km, which is close to the max 25 km range of Phoenix radar in WT.

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DCS is wrong about the performances of the rocket motors so I’m not certain I can trust them on everything else. I’d need more sources.

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Regarding the rocket motors propellant weight being incorrect; I have put in a report on this issue.
https://community.gaijin.net/issues/p/warthunder/i/r8SdwCrLivnX

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Regarding the AIM-54A in DCS vs the AIM-54A in War Thunder and IRL, I will do a comparison;

Spoiler

Weight (mass)
IRL- 978 pounds (443.613kg)
DCS- 444kg (rounded I guess?)
WT- 443.613kg

Fuel mass
IRL- 165.108kg (364) pounds of Flexadyne (CTPB), RDS-500 series
DCS- 163.3kg (360) pounds
WT- 170.55kg (376) pounds

So it seems while war thunder has the correct missile mass, and DCS didn’t bother to put in an exact number (rounded to nearest non-decimal)… War Thunder has the incorrect fuel quantity.

DCS marks the Mark 47 Mod 0 with “Flexadyne” as high smoke and the CTPB Mark 60 motor as “Medium” despite them both being a type of CTPB propellant with no serious distinction besides the choice of oxidizer, which does not change the quantity of aluminum in the propellant… So it should both be “high smoke”.
DCS also marks the Mark 47 Mod 1 motor as smokeless, when this should only be reduced smoke.

The idea that the HTPB in the Mark 47 Mod 1 has higher ISP than the CTPB is wrong, DCS’ has this backwards. The CTPB propellant has a higher ISP due to the added aluminum and the reduced smoke motor would be slightly lower overall performance due to the differences in specific impulse in HTPB and CTPB type propellants. The Mark 47 Mod 1 in the AIM-54C also has less propellant, at only 360 pounds vs 364 in the Mark 47 Mod 0.

I’ve gone over the AIM-120B and AIM-54 and it seems there is no consistency with DCS regarding missiles. Some stuff is dead-on to the hundredth in terms of accuracy regarding the numbers, other stuff is rounded to the nearest whole number. Some information they used for their missiles is just wrong (AIM-120B mass, AIM-54 motor information). The common trend it seems to me is that despite using “subject matter expert” opinions on many aspects of the sim DCS has incorrect information to model their systems off of. The AIM-54 and AIM-120B are great examples, as is the Mirage 2000. Using DCS as a source is generally going to result in no more accuracy than quoting from random websites, as it seems they have derived a great deal of data from outside analysis (guessing) and corrected it over time as real data is presented.

Regarding war thunder, I think sufficient public information exists to model the AIM-120 and AIM-54 more accurately than DCS has thus far… if Gaijin pays attention to these threads… or actions on reports sooner than they have in the past.

Also,
if you wanted, here is a photo of the various parts of the radar and guidance system for the YAIM-54A

The radar is known as the “AN/DSQ-26”. You can see the antenna, electronics, batteries, etc. On the tail end is the control fin, and the cable links that go around the propulsion system.

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Great post, thanks!

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Ima be real, War Thunder will never be more realistic than DCS or Falcon BMS full stop until gaijin chooses to fully refactor how missiles work in general.

Remember, missiles in WT are functionally the same as torpedoes, yes the torpedoes launched from ships, along with SARH and ARH missiles being modified IR missile code, modified to mimick how each type of homing works.

To compare the spaghetti that is WT to functionally any other sim is a disservice to pretty much anything you compare it to.

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War Thunder is not a sim, and yes it’s missiles are more realistic than DCS in a multitude of areas. It goes both ways, though. Let’s not pretend DCS is even remotely above war thunder as a flight sim since everyone wants to quote it for realism and yet the only focus they truly have is in making sure the buttons you click imitate what they do in real life.

DCS’ missile motor arrangements for the Phoenix are just plain goofy and almost solely based on the data put out by a forecast international magazine from the 90s. Their AIM-120 data looks like it was pulled off wikipedia for the most part. Their Mirage 2000 out-rates any other fighter in the game. The MiG-29 they have pulls obscene AoA and can easily do 16G turns on a whim. Anything they’ve modeled “accurately” was done after the fact and after ripping through the actual NATOPS (F-16, F-14 etc) and in some cases, sourcing that data illegally… lol

As for War Thunder, the missiles don’t NEED to be modeled down to the minute details. That’s how efficient code works, it imitates what it needs to for some semblance of realism and that’s enough. Anything “extra” is just unnecessary and overly complicated.

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“efficient code” - “war thunder”

You can pick one, you cant have both, as I have already shown prior.

To that same end its already been made blatantly clear numerous times before this that you do not know what you are talking about in terms of BMS or DCS, instead carrying along what seems to be a rather large vendetta against both titles for unknown reasons.

You are after all somehow comparing a game that refused to add in lofting for almost a year and 3 months on a missile who’s primary flight characteristics relied solely on lofting to operate in it’s primary role, yet here you are saying somehow WT is even remotely more accurate than actual proper sims.

Come to think of it, we’ve come back to this exact issue more than a few times at this point, with nearly identical arguments pertaining to a multitude of subjects that have been proven moot multiple times now being brought up as fact once more.

No missiles DO need to be modeled down to minute details as thats what defines the actual differences between missiles IRL, you either arcadeify all of them like WT currently does, along with putting a venire of realism over them or actually model proper missile mechanics like BMS or DCS. The entire skyflash family is probably the best example of all of this, being functionally just AIM-7E-2s with no actual modeling of the benefits they have over their standard sparrow counterparts when they existed IRL because WT does not care about such small details.

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“The issue is that what you are asking for from War Thunder is minute details that DO NOT MATTER in the long term for gameplay in an arcade game. We can’t pretend war thunder is a sim, it’s not. Nowhere has it ever been declared a “flight simulator”.”

Ok no I’m not even going to humor you anymore if you carelessly sweep your statements on the previous forum under the rug that easily, thank you for finally showing your true colors on this subject, you have fully proven to me that you do are not interested in good faith discourse.

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The secondary source you cite says that the mk.60 is “functionally” the same.

The adjustments they’ve made on the linked patch notes has the missiles functioning pretty closely in final results. The mk.47 with the longer burn performs slightly better in short range engagements, and the mk.60 slightly better in very long range shots.

I’m curious what items you think they are so off base on, and whether that’s a function of poor research or ED’s failure to give Heatblur a custom API to properly implement the missile.

I know we’re focusing on getting an accurate version of this missile into WarThunder, but a lot of people have an impression that Heatblur’s implementation is pretty definitive. It might help if you pointed exactly where you think they are so off base and why.

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will have a possibility of a changelog to change the burn time of aim-54A and its thrust, same as aim-54C, but with active seeker turn on if you don’t mid-course it?
And how works the ability to fire 6 phoenixes at 6 different targets at once?