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

Yep exactly, iirc R-77 is lofting in game which is incorrect right? I imagine the motor will get turned up to compensate.

Mainly yes but they would want to test accurate missiles

The balance dynamic of R-77 and AIM-120B will be quite different once fixed

Fairly certain the R-77 doesn’t loft, so that appears incorrect. I’d need to reference their datamine again for that missile but I’d rather do it in the R-77 thread.

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I suspect the R-77 we have is supposed to be an R-77-1? the 3D model is a -1 and the performance seems closer to that

Who knows, but I find this unlikely as the motor stats match the standard R-77 data. Let’s move to the other thread.

Here are the results of my AMRAAM testing on the dev server. All results are for head on launches against co-speed, co-altitude, non-manoeuvring targets:
image

I’ll investigate rear aspect performance next.

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Where does the expected comes from?
Want to test this? Fire an aim120b flying at mach 0.94 520kts airspeed, 11k ft at a target flying towards you at 10kft 364 kts IAS. Vc should be ~1020 kts with this geometry. Ezzy and fire at 17.5km. SHould take like 17seconds to reach target

Performance seems to be very accurate, id attribute it primarily to poor lofting performances. Gaijin models missiles for rear aspect performance at 3-5km alts universally. Most missiles in-game ‘underperform’ in maximum range shot conditions by similar amounts.

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Alot of the lofting at longer ranges seem off due to missiles shaking too much ( im sure their is a better word for that )

The oscillations affect the missiles with TVC and higher fin AoA the most, such as the MICA and R-77

Yeah hopefully they fix it when they come in june

I hope that there is a dev update Monday so we can Atleast test accurate missiles in this test phase to see the missile dynamics.

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The National Archives and specifically Royal Aircraft Establishment (RAE) testing documents.

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Be wary of the claim it is battery limited, that does not mean it should have kinematic energy remaining to hit a target even at ~1G much beyond what was stated. Documentation for AIM-54 also shows potential for more than double it’s current range if battery life was unlimited… But floating down from space while waiting for a target to approach you is not truly “extending” the reach of the missile in a meaningful manner.

It is nearly drained of energy and coasting while losing altitude in these conditions mentioned for a high ballistic range trajectory when truly, the target is just getting more time to approach.

Additionally, it is not far off from the stated ranges. The wobbling and oscillation issue as well as incorrect loft profile cause a reduction in range performance to what is expected.

And to top all of that off, Gaijin tends to test in rear aspect scenarios for these missiles at 3-5km alt and sometimes the peak maximum range performance is less than expected from missiles (such as the case of the R-27 series for example).

Well the rear aspect range is underperforming to a much greater degree than the front aspect range currently: Community Bug Reporting System

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Then I look forward to seeing changes 👍

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How does that work? Trying to wrap my head around the idea of a missile underperforming in rear aspect to a greater extent than in front aspect. The lofting mechanism has to play a part in it I suspect.

rear aspect will be limited more by energy, and front aspect more battery life is my assumption. So i would expect it should have a greater impulse motor and or less drag, but the loft should be a greater angle, the higher distance travelled will mean its frontal range will be increase less than rear aspect. (oops deleted it)

I think these are primarily issues with the efficiency of lofting and drag of the missile overall as the thrust and performance matches known primary source material given in my OP.

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