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

This argument makes no sense.

How is a missile (which already accelerates to mach 3+, and is designed to handle 20g+ manouvers) going to have any negative effects whatsoever from being launched at mach 1+?

Like aerodynamic heating maybe? But they already do mach 4 how is another ~.5 mach increase going to do anything?

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Its LITERALLY your own damn chart. Arguing with you RU fanboys is like speaking to a fking wall ffs:

If the math is a little too hard for you, here you go;

1400m/s - 500m/s = 900m/s

EVEN IF you wanna argue the launch speed is “not quite 500m/s” its at worst 480m/s, and nothing you say actually even disproves my point.

Stop wasting time with all this off topic garbage

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Did you read what he said?
Also my calculations show approximately 942 m/s DeltaV for the missile, which seems to mean it is accurate.
https://cdn.discordapp.com/attachments/955829235493273680/1156344222530670703/image.png?ex=6514a0fa&is=65134f7a&hm=70451a8a51f19014dd2cd8c9616522e9534fbe8ee108e02ced5bb1b87726252c&

I’ve done similar stuff for the AIM-120 and seen based on public information anywhere from 833 to 904 m/s deltaV configuration and I CANNOT STRESS ENOUGH how this is irrelevant when comparing two different missiles of two different sizes with different burn profiles and different aerodynamic characteristics such as grid fins vs conventional fins.

It makes no sense to those who have no knowledge of the forces applied to the launch platform itself. When a missile sits on a rail flying the speed of sound. The missile will buffet. You can actually jam the missile and it will ignite and not separate. Thats why to release at such speeds you must be at a high altitude. It is a delicate process for SUPERSONIC separation. With failure rates increasing the lower you are in the dense atmosphere.

That is why certain aircraft were designed to drop them instead.

All you know if video games like my dear friend.

“the missile flies fast already!” is their argument. lol.

I like how this “0.9 to 1.2 mach” number has been completely pulled out of your ass despite evidence indicating that the transonic choke effect actually extends across a much wider drag range. I.e. this NASA study you can see the onset of the effect in wind tunnel studies around Mach 0.75 in the axial drag coefficient section, and this USAF study shows a similar onset. The effects of this fade but they don’t vanish until high supersonic speeds(above Mach 2).

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Please cite sources and provide any reason to give you benefit of the doubt.

Generally stuff closer to the airframe drops to avoid smoking up the intakes and wing mounted stuff goes off rails since it isn’t as much of a concern.

Please reference the sources shared previously by the Russians on their own missiles.

Source, then? Like we can see both the papers I listed and references in those papers give a onset range from around 0.75-0.82 mach and a fade until around 2.0-2.5 mach. Aerodynamics is the same for everyone and there’s a considerable body of research in the US literature on grid fins.

@Aetreus

the best study in Belotserkovsky’s book

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Which what, I am supposed to go buy and trust that it proves how wonderful grid fins are, sight unseen?

I don’t know, it’s your choice, you can model the missile like I did

Yes, because some random person on the internet is comparable to NASA/USAF studies on the subject? Yeah right, pull the other one.

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Yo, bbc. Let’s keep it real though. The only reason you support anything my bud has to say is because he is not undermining soviet weapon systems. The second he does your honeymoon is over with.

I’ve been buffing a metric shit ton of NATO equipment such as Magic 2, Phoenix lately and you ignore that conveniently because you think I report only in biased manners. The only person here who has a bias is you, against me for reasons far more personal than game or forum related. Stop stooping to this level, as I said, it’s beneath you.

I am for objectivity

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He does not know that shhh. There you go.

The Russian document is better sourced for the Russian missile than is the American ones imo.

1:05 target Su-27 speed 0.8M

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So there is what, some sort of magic Russian sauce that makes their grid fins better than US ones? Despite the fact that American studies were done with at that point knowledge of the R-77’s configuration, and that the R-77 includes no obvious optimizations to reduce flow choke(i.e. sweep of the lattice leading edges, coarse grid geometry).

Also saying “the Russian document” is ludicrous when no-one has even said what document it is, let alone actually presented an excerpt from it.

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Interestingly, we can see the fins maneuvering in the same way the Phoenix does (“X” config) here. I think this is proof it maneuvers in combined plane, should have a 50G overload in-game.