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Elite 1K Joined: Aug 19, 2004 Posts: 1090

Pilotasso wrote:

There are some videos out there showing it flying all the way to the target drone. Wink

http://www.patricksaviation.com/videos/Guest/18/

Uploaded this myself.

Missile snapping off 90ºs to one side will be flying much slower than the brochure mach 2.5. Thrust vectored off boresight shots have drasticaly reduced range, 2-3 miles as oposed to 8 miles max in brochure.

Umm.... what you're saying is obvious. Max range figures for any missile are for optimum firing conditions. Max range for an AIM-120 at low altitude against a target flying away from it at Mach 1+ will probably be less than 8 miles too. I don't know where you got the idea that the AIM-9X would be used to fire at targets 90 degrees angle off from max theoretical ranges, but this simply isn't how it will be used. High off borsight shots will be used against targets at relatively close ranges. Normally the pilot will be able to see the target (hence the helmet mounted sight). The missile will not have to go Mach 2.5 or fly for very long to hit its target. The idea is to fly fast enough and turn tight enough to hit a target at extreme aspect angles and closure rates. For a dogfighting missile like the AIM-9X, a rocket motor burn time of 4 seconds isn't bad at all. What did you expect the burn time to be? Dogfighting missiles can't have a large rocket motor. It would make them too big and heavy for use in a dogfight. Why is an AIM-9X not the size of an AIM-120?

Again, you can't go by what the missile brochures say unless you're talking about ideal conditions which almost never happen in combat conditions. The AIM-9X is still a very impressive missile and can do impressive things? You think it should be better? You think it's too slow? What? I don't understand. How is it lacking in comparison to other dogfighting missiles? You make the AIM-9X out to be some sort of failure. Craziness! Smile

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Raptor_One wrote:

Umm.... what you're saying is obvious. Max range figures for any missile are for optimum firing conditions. What did you expect the burn time to be? Dogfighting missiles can't have a large rocket motor.

I didnt expet anything like you say, was just making a comparison base and stating that thrust vecoring manueverability only occurs on that time frame and range. I think that was even more obvious. Wink

Pilotasso wrote:

mil_hobbyist wrote:

Thrust-vectoring should compensate for large control surfaces. Don't forget that the -9x is designed for 90-degree off-boresight shots.

But the missile motor only bruns for about 4 seconds, furthermore the missile will be much slower and have much less range in off boresight shots.

Elite 1K Joined: Aug 19, 2004 Posts: 1090

Your reply to mil_hobbyist implied that the lack of large control surfaces in favor of thrust vectoring was somehow a design flaw. Clearly the AIM-9X is designed to engage targets at relatively close range, just like the AIM-9M and almost all other IR homing short range missiles. An effective AIM-9X shot will be taken at relatively short range, regardless of the aspect angle. The AIM-9M wouldn't be fired at targets 8 miles out (if it could get a lock at such that far out in a tail chase situation). The -9X's more advanced IIR seeker will enable it to engage targets head on at much longer ranges than the AIM-9M. The -9X's small profile gives it less drag, and hence more range than the -9M.

There'd be little reason to fire the -9X at high aspect, off borsight targets at the published max range of 8 miles. You'd just turn into a target that far out and fire the -9X at optimum conditions (i.e. the right amount of lead given the targets altitude, speed, heading, etc.). In this scenario the -9X wouldn't have to use its thrust vectoring and would reach higher speeds than the -9M. Once the motor burned out, it would be going faster than the draggier -9M. Its smaller fins will probably be just as effective at these higher speeds than the -9M's larger fins at lower speeds. The -9X will also lose energy at a slower rate than the -9M once its motor burns out. Again, less drag due to the smaller control surfaces. In other words, the -9X will be just as capable as the -9M in terms of making final course corrections after its rocket motor burns out. Why? Because it will be going faster.

At ranges where the -9X and -9M are both highly effective, the -9X will be more effective because it's more maneuverable. For high off borsight conditions at optimal ranges, the AIM-9X can still engage while the -9M can't. Perhaps there's a very small portion of the engagement envelope where the -9M is superior due to its bigger fins, but I somehow doubt it. The -9X is just a better missile design. It's more capable in just about all scenarios than the -9M, if not all. Also, thrust vectoring may be used to a smaller degree for more effective maneuvering when fired at less extreme conditions. Small fins plus thrust vectoring may very well be better than large fins and no thrust vectoring in situations where either design would do the job. The combination of small fins + thrust vectoring on the -9X may result in less induced drag at moderate to high angles of attack compared with the -9M under similar flight conditions.

My point was that controll surfaces are not the same as thrust vectoring ( I was thinking on the python 5 wich has a greater range), while any other agile missile will use the controll surfaces at any stage of the flight the 9X will have to be in a favourable trajectory by the time the motor burn out in order to hit home using its small surfaces only, theres a difference (again I was thinking on the python 5 claims that large advanced surfaces are better than thrust vectoring), I wasnt even thinking about he 9M, but good post anyway, I agree with what you said albeit being a bit off from what I was trying to point out.

Cheers.

Elite 1K Joined: Aug 19, 2004 Posts: 1090

Like I said, the AIM-9X is much less draggy than most other dogfighting missiles and will thus be going faster after motor burnout for somewhat long range shots. The higher the speed, the more effect the control surfaces have. Hence the smaller control surfaces.

Hmm.. I'don't know..
Since it seems that USAF is non so interested in range performance (talking about short range aam's) as agility and HOBS characteristics, I suppose that to let the old bigger control surfaces it would have been the correct choice.. i still hope that there is another reason..

Elite 1K Joined: Aug 19, 2004 Posts: 1090

Neno wrote:

Hmm.. I'don't know..
Since it seems that USAF is non so interested in range performance (talking about short range aam's) as agility and HOBS characteristics, I suppose that to let the old bigger control surfaces it would have been the correct choice.. i still hope that there is another reason..

C'mon now. Are you seriously trying to say that Raytheon didn't know what they were doing and made a missile with control surfaces that were too small to meet the requirements set forth by the USAF and US Navy? Just because you don't understand why the AIM-9X doesn't have both large control surfaces AND thrust vectoring doesn't mean the AIM-9X should be redesigned to have huge control surfaces! You are basically saying that Raytheon and the USAF/USN made foolish decisions and that the AIM-9X won't be agile enough to do the job it was designed to do. Raytheon and the Pentagon analysts should have consulted with you first, I guess. You would have told them to put bigger control surfaces on the AIM-9X and it would have been a better dogfighting missile. How silly of them! Rolling Eyes

No Raptor_One, obviously i wasn't..
I still (only) hope this characteristic is a symptom of an intention to fit 2 aim9x in a single side bay.
Scorpion, don't be amazed, this is simply a my hope.

Elite 1K Joined: Aug 19, 2004 Posts: 1090

Neno wrote:

No Raptor_One, obviously i wasn't..
I still (only) hope this characteristic is a symptom of an intention to fit 2 aim9x in a single side bay.
Scorpion, don't be amazed, this is simply a my hope.

Huh? No, that's not the reason why they have small fins! They have small fins because they don't need larger ones to meet their requirements. What's your deal, man?

Obviously the 9x is a good missile, my country is studying its aquisition. But I would still prefer to use a more expensive but less risky AMRAAM further out. Wink

Elite 1K Joined: Aug 19, 2004 Posts: 1090

Pilotasso wrote:

Obviously the 9x is a good missile, my country is studying its aquisition. But I would still prefer to use a more expensive but less risky AMRAAM further out. Wink

What do you mean by further out? Most aircraft would carry a mix of AIM-9X and AIM-120. You could use either one.

I know, But I would feel better taking an enemy 4-5 (if not BVR) miles away than having to resort to the helmet on an off boresight shot, because then I might be in trouble anyway.

Elite 1K Joined: Aug 19, 2004 Posts: 1090

Pilotasso wrote:

I know, But I would feel better taking an enemy 4-5 (if not BVR) miles away than having to resort to the helmet on an off boresight shot, because then I might be in trouble anyway.

That's why most fighters carry more medium range missiles than they do short range missiles. I don't get what you're trying to say. Are you trying to say that you think short range missiles are completely useless?

I think he's trying to say that he would rather not be put into the situation to use a short range missile

Elite 1K Joined: Aug 19, 2004 Posts: 1090

sprstdlyscottsmn wrote:

I think he's trying to say that he would rather not be put into the situation to use a short range missile

Yes, but that would once again be stating the obvious. My question to that statement is, "What's your point?" Stating something obvious doesn't mean you have a point. Smile

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