F-104 TAS dodging AIM-9M fired from AH-1Z

Why are missile physics when attached to a helicopter non existent?

When fired from a plane, the missile inherits it’s current velocity and altitude making it much more effective. Helicopters typically fire their weapons when stationary and at low altitude though, so the the missile is entirely dependant on its motor.

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Yes why does the motor of the AIM-9M not work?

After watching the replay, you never fired a missile at the 104. The only plane you fired a missile at was a tornado over 4km out flying away from you.

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Because it’s not a very big motor. It’s not really supposed to be fired while stationary.

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Bell disagrees with you.

It is the same missile. But a plane is moving at Mach speeds when it fires the missile thus the missile is already supersonic and having a bigger range. A helicopter is not the same as a plane

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Of course it would impact range (due to the lower closure rate), but not by as much as you think. Since you aren’t going to find helicopters at that high an altitude, or likely to shoot at targets from the rear aspect which eliminates the low / negative Closure rate that would restrict range.

Range is going to be more heavily impacted by drag much more so than closure rate in most realistic scenarios near sea level.

Hes not trying to say its a different missile you cretin the difference is firing an Aim-9M at 1100kph means the booster can get it to mach 2+ and sustain its speed while tracking a target, while firing it from 0kph on a heli the booster might make the sidewinder reach mach 1.3 for a short time and only be useful in a front aspect

“not really supposed to be fired stationary”

Do you think Helicopters are moving very fast? You think Bell hasn’t taken that in to account when utilizing AIM 9s as its heli to air option?

Compared to a Stinger it’s a large heavy missile that produces a lot of drag. It’s one of the reasons why fixed wing aircraft air-to-air missiles are not often used on helicopters.

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I think their main motivations were:

  • it’s better than a stinger simply because of it’s size

  • their customers already have them in inventory

  • cheaper than designing a new designated missile

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The thing with (Super) Cobra(s) is that the design is old, so when the Sidewinder / Focus / SideARM (AH-1J, entered service in 1971) was integrated it was really the only serviceable option for air to air missiles

The Falcon was never going to work within the limitations of fixed wing aviation and an IR guided Sparrow would be far to heavy for helicopter use.

The fact that it also did well enough to never really need a direct replacement (trials using a variant of the Redeye [FIM-43] optimized for Air to Air use did occur, from which the Stinger is also a derived from, but never really went anywhere due to the Rear aspect Seekers of the time and lacking IRCCM capabilities[only truly fixed with the AIM-9M / FIM-92B(they both began production in the early '80’s)].

Especially since the hardware to mount Sidewinder had already been developed for the UH-1[AGM-87] anyway, and that helicopters rarely ever had to deal with fixed wing aircraft and the 20mm turret was already overkill for rotary threats considering that they predate threats like the Mi-24 by a few years, so the most likely thing to be running into was the Mi-4 /-8 or other early helicopter designs.

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Unfortunately, in most instances I’ve seen, you’d be lucky to fire off an Aim-9M at a jet in front-aspect if you weren’t looking for them in the first place, and if you do, the Aim-9M may not even hit (due to the aircraft flaring it off). That leads to, in most cases, the AH-1Z having to shoot the Aim-9M when the plane had already passed them, and therefore it would be a rear-aspect shot.

Physics still dictate that the velocity of the firing vehicle is added to the velocity of the fired missile. So if fired with a starting velocity of 0, obviously the missile already has to use up a significant part of its propellant to reach the same energy it would have if fired from an aircraft flying at fast subsonic speeds (or faster).

So obviously the envelope of a missile fired from a helicopter is much more rerstricted than the envelope from the SAME missile fired from a fast mover - even more so of course if fired form an advantageous position altitude-wise (higher up: less drag, also if fiiring at target lower than yourself higher potential energy…).

And Bell didn’a say anything about the performance of the missiles fired from the Viper, just that it can be fired…

(And I also have to say that if someone fires a Sidewinder from a heli at a fast jet flying away, which is already 4km out, he hasn’t really understood those physical aspects, sorry.)

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You’d be lucky to hit an Aim-9M rear-aspect in a helicopter even when the jet is going mach 1 and is only 2km away after you fired it.

Exactly.

Welcome to basically every Vamilad thread

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The motor is the same, but it’s fighting gravity with no help. You don’t inherit a high velocity from a helicopter - so the missile is also competing to overcome the distance and speed it never started with.

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The TY-90s are a much better helicopter anti-air missile than the Aim-9M will ever be, despite the TY-90s fairly recent nerfs. Arguably the mistrals and iglas too.

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