The AIM-120 'AMRAAM' - History, Design, Performance & Discussion

This is the second time @MiG-23M lied or about a source’s provenance and it seems completely pointless to continue arguing with someone when they’ve demonstrated that they’re not debating in good faith.

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You know very well what you did. Handing these sources off to me as legitimate and then turning around to paint me as guilty like this.

This also doesn’t change the fact that all of the graphs in the second book match the real primary source manual diagrams and charts for range on the remaining missiles. It’s highly likely that the R-77’s is accurate as well.

@Aetreus The argument stemmed from the fact that the R-77 outperforms the early AMRAAM’s, AIM-120A/B. I made the point that the first AIM-120 that would properly compete is the AIM-120C-5. This has not changed, and whether the R-77s max range is 80 or 100km doesn’t change that fact either. That will only really determine if the AIM-120C-5 will compete with, or beat it outright.

And @MythicPi if you still want to try and prove the AIM-120A/B is comparable to the R-77 I’d be happy to see you use napkin math or the same methods and reason as I have used to find the range of the missile. If you want to stick to your guns and not be a hypocrite about this you can go ahead and find any reasonable source to suggest the AIM-120A has more range than the AIM-7F/M barring guidance time and lofting.

Yeah no point in arguing anymore, I’ve just muted him.

Back on topic for the AIM-120, ill dig around and see if theres anything more I can find besides the source I already posted. Since it came from a mod, Gaijins already got eyeballs on that one, and beyond the fact that it indicates the AIM-120A matches the AIM-7M range and exceeds its envelope to the sides with conventional guidance, and exceeds its range with command inertial guidance, it doesnt give us any hard numbers beyond “better than AIM-7M”.

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Pointless muting someone who runs the thread and has more knowledge / information on the topic. I’ve already passed most public sources to the mods on the topic. In fact, they approached me for further information in the first place.

When you discover what I’ve said is true don’t be afraid to post it and admit as much.

I’m not painting anybody here. I only discuss misisles here and free to constructive dialogue. What’s wrong with showing that source you posted isn’t official and quite old, possibly outdated and perhaps not converging with reality?

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You had these sources, you knew that the RVV-AE is the export model yet failed to provide the information and when you did share it with others it was misrepresented. When someone posts it as it was shown to them you only take the time to correct them after it was posted here?

Yes let’s remain constructive and instead of attacking “napkin math” we can continue to make inferences on the performance of missiles without relying on arbitrary and inaccurate statements from the governments who produce them. The AIM-120 is clearly >20 miles maximum launch range, just the same as the R-77 is clearly capable of more than 80km. It would be considered dishonest imo to state that 80km is even the effective range of either weapon anyhow.

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I’m working on a working AIM-120A/B model in war thunder using the public data.
I don’t have real thrust figures, but using the burn times discovered and ISP of the HTPB propellants I’ve found a thrust that correlates. Adjusting the drag model to be between two missiles larger and smaller than the size of the AIM-120 has yielded the following results, and I’ll compare against R-27ER.

Co-altitude 10,500m target and launch aircraft.
Both locked at 1,200 km/h. Launch at 60km.

AIM-120A hits in 79s.

R-27ER hits in 52s.

This leaves approximately 27 seconds for the R-27ER launching aircraft to defend in this particular scenario. Honestly, I think the AIM-120A could come to the game very soon and it would be matched against the Russian aircraft equipped with R-27ER. (Albeit some AMRAAM slinging aircraft simply have more missiles).

Also take my testbed model of the AIM-120 with a huge pinch of salt. I’m working on estimates here, although at least well founded ones. The ISP, thrust etc could be way off since I’m guesstimating the thrust based on known propellant weight and burn time.

Note;
I tested the missile with an infeasibly low drag coefficient as well
(same CxK as AIM-7F albeit much smaller “caliber”)
Time to target dropped to ~69 seconds. This is still 17 seconds later than the R-27ER for a 60km launch in these conditions.

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Testing again, I found that the R-77 beats the AIM-120A/B test model to target as well. The time to target is approximately ~65s to the AIM-120’s best case scenario of 69s (and more realistic time to target of 79s).

Excuse the AIM-120C model, looking for an R-77 model to insert currently but wanted to share the results sooner.

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I found a source which states more clearly the fact that the AIM-120 uses instability to improve energy conservation and range as well as maneuverability.

Particular section;
In Russian
In English

https://www.gosniias.ru/index-e.htm#5

This is a “source” the same way “it came to me in a dream” is a source. A Russian state funded research institute commenting on a western missile is about as reliable as that Indian defense blog from a few days ago

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I did not include in in the OP of the thread for a reason, rather just shared something public that states something interesting about the missile. They also cited a number of sources for their information at the bottom of the page.

Its also just an erroneous understanding of what his source states, seeing as it specifies “the feature is a method of minimizing energy consumption by the drive” and speeks of the hinge moment.

This is literally just talking about how the missile minimizes how much effort the fins actuators (or drives) must work…

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This makes sense, I’m looking for more information on the “high-angle off-boresight capability” of the AIM-120C variants stated in various sources.

AIM-120C-7 initially seems to use the +5 motor from the AIM-120C-5, but later replaces the “SCAS” (shortened control actuator section) with “VCAS” (value control actuator section) and also received a replacement rocket motor from the firm “NAMMO”.

From what i understand , the C7 initial upgrade was new software to improve the resolution and interference immunity of the WGSN.
Later from lot27+ the use of a more modern oand compact element base (VCAS?) made it possible to increase the length of the engine bay and so more propelant = more range (120km vs 105km Max range)
The NAMMO remplacement motor was only a motor that could be use in cold temperature (ie Norway) because the initial one wasn’t working well for higth altitude cold air shot. I don’t think the motor was better in way than the atk one in performance.

NAMMO motor seems to have been offered at some point but only to those with VCAS modification which is why I presume it has higher performance similar to the lot27+ motors made by Orbital ATK but could be wrong. I also see no reason NAMMO couldn’t have helped produce both motors as well.

This has been a very interesting thread to read

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It is there and I did testing of it with a friend immediately after release, it works on F-14A Early at least with at least 2 missiles.

That is not giving multiple guidance, that was missiles own INS , now due to loft code , it is more inaccurate and needs the guidance by the radar .

This is the data of the aircraft of both sides in the China-Thailand military exercise. The Aim-120 has a range of 80km, but the R-77 has a range of 50 km?
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