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Russia new generation fighter

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posted on Jul, 5 2006 @ 08:56 AM
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Originally posted by Aim64C

Originally posted by Laxpla
The F-23 didnt have unparalleled in its maneuverability against the F-22. The F-22 won because that mostly that reason itself.

And the F-22 does incorporate some kind of IR reduction. A new ceramic-matrix RAM on engine exhaust nozzles to reduce radar and IR signatures.



Wrong - the F-23 was far more maneuverable in high-speed engagements. The F-22 did have superior low-speed handling due to its ducted thrust. However, since it is a standard aircraft, it suffers performance loss as speed increases.

The F-22's IR reduction is fruitless. You're talking a difference of, maybe, 5% - most of the exhaust is expelled before any cooling can take place. The airfoil of the Raptor is, in a way, designed to mix the flow from the root of the main wing, around the horizontal stabilizers, and into the exhaust stream. However, this fails to substantially reduce the IR emissions. Considering an Aim-9M can lock onto a cigarette from a thousand feet away - one will have no problem picking out a Raptor.

The hope is that the raptor will be able to out-maneuver the missile, allowing it to veer off towards countermeausers or just get confused.

The F-23 was the true ATF - the F-22 is a repackaged F-15 with 30% of the capability.


Wrong. Can you provide a link stating that the F-23 had overwhelming maneuverable in high-speed engagements verses the raptor. It may be on Par at high speed, but Thrust Vectoring would dominate in a low speed, close range. Thus giving the upperhand to the raptor.

You contradicted yourself, your telling me "Wrong" when I was right? You stated the Raptor has excellent low speed handling.


Well maby if it is a 5% decrease, its better to have SOME decrease the NO decrease. Maby a couple extra seconds can be bought with that decrease thus every second counts, and could save a life.




posted on Jul, 5 2006 @ 10:41 AM
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The YF-23 did not have to use its ruddervators to achieve pitch or roll movement - slight adjustments to the leading and trailing edge of its wings gave it more than enough control during supersonic flight (and you still want to maintain consciousness). Its low drag and high instability also made it much more maneuverable by default - since less force is required to get the aircraft to change direction.

There are a couple things that kill the thrust vectoring 'advantage'. First, during supersonic flight - the movements of the control surfaces are inverted. However, the movements of thrust vectoring are not. Meaning that extending your vectoring nozles into the airflow is always resisting the force exerted by the thrust of the engine. Also, the rate of pitch and yaw through thrust vectoring is affected only by the amount of thrust the engine is producing. The pitch and roll control provided by thrust vectoring on the F-22 are also reduced by the resistance to movement by the large control surfaces.

The F-22 is a stable design - which is good for the old cable controled systems, but not bringing out the full potential of fly-by-wire. The F-22 has to move entire control surfaces to obtain movement, where the F-23 only has to make a couple of minor adjustments to the wings' leading/trailing edges in combination with the ruddervators to achieve maneuverability in supersonic flight (as well as high subsonic speeds).

These combined together mean that the F-23 will always be superior to a 'normal' aircraft in supersonic flight.

'Official' documents of the F-23's performance don't really exist - unless you want to take into account the refferences made between the two competitors in the decision to choose the Raptor. There weren't very many flights of the YF-23, either - they didn't even give it the chance to test the YF-120 engine - which was not ready for the prototype - so, rather, only the YF-119 engine was used for the ATF competition.

The 'official' claims were that the two were rather close in performance. However, comments by people who worked on both programs have said that the YF-23 was vastly superior in speed and maneuverability. NASA was given the two prototypes to do aerodynamic testing on because no other aircraft in the world has ever come close to its performance.

YF-23 on Globalsecurity.org




According to the Air Force, factors in the selection for production of the F-22 were a better designed for maintainability, greater potential for future development, and slightly lower cost. Secretary of the Air Force Donald B. Rice stated that the choice was based on confidence in the ability of the Lockheed team and Pratt & Whitney to produce the aircraft and its engine at projected costs.


I find that ironic.



posted on Jul, 5 2006 @ 10:54 AM
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From what I've heard the F-22 is actually an unstable design and that it was in fact more manuverable. The YF-23 was stealthier and quicker in accleration and top speed.

[edit on 5-7-2006 by JFrazier]



posted on Jul, 5 2006 @ 11:01 AM
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The YF-23 was NOT superior in acceleration. The plane had a somewhat lower thrust-to-weight ratio.

The F-22 is a stable design. Scale model RC aircraft of it can easily fly with no difficulties. However, the F-23 requires fly-by-wire to fly - without it, you could fly straight until you hit any sort of turbulance.

The claims of the F-22's performance by the people who created it are also overdramatic. Just as the claims of the F/A-18 E are.



posted on Jul, 5 2006 @ 12:01 PM
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I suspect much if not all of the room to mask IR signatures is taken up by the 3d vectoring nozzles that the Russians love so much, it will be interesting to see if they can manuver enough to dodge missiles.



posted on Jul, 5 2006 @ 12:07 PM
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Origihnall posted by aim64crong - the F-23 was far more maneuverable in high-speed engagements. The F-22 did have superior low-speed handling due to its ducted thrust. However, since it is a standard aircraft, it suffers performance loss as speed increases.

The F-22's IR reduction is fruitless. You're talking a difference of, maybe, 5% - most of the exhaust is expelled before any cooling can take place. The airfoil of the Raptor is, in a way, designed to mix the flow from the root of the main wing, around the horizontal stabilizers, and into the exhaust stream. However, this fails to substantially reduce the IR emissions. Considering an Aim-9M can lock onto a cigarette from a thousand feet away - one will have no problem picking out a Raptor.

The hope is that the raptor will be able to out-maneuver the missile, allowing it to veer off towards countermeausers or just get confused.

The F-23 was the true ATF - the F-22 is a repackaged F-15 with 30% of the capability.
You obviously don't know what you're talking about the F 22 IR reduction is very significant. Why don't you post a source about the Raptor not having significant IR signature.


Infrared radiation (heat) should be minimized by a combination of temperature reduction and masking, although there is no point in doing these past the point where the hot parts are no longer the dominant terms in the radiation equation. The main body of the airplane has its own radiation, heavily dependent on speed and altitude, and the jet plume can be a most significant factor, particularly in afterburning operation. The jet-wake radiation follows the same laws as the engine hot parts. Various ways have been developed and tested to cool down the engine exhaust gasses. The ilustration above shows how the hot exhaust gasses can be surrounded by cooler air, significantly reducing the IR signature of the plane.

Air has a very low emissivity, carbon particles have a high broadband emissivity, and water vapor emits in very specific bands. Infrared seekers have mixed feelings about water-vapor wavelengths, because, while they help in locating jet plumes, they hinder in terms of the general attenuation due to moisture content in the atmosphere. There is no reason, however, why smart seekers shouldn't be able to make an instant decision about whether conditions were favorable for using water-vapor bands for detection.
www.f-22raptor.com...








Radar absorbant materials, or RAM is applied sparingly on the F-22 airframe as opposed to the entire airframe on the F-117. This is because designers have incorporated curves on crucial surfaces and edges, which lessens the need for RAM. For example, new ceramic-matrix RAM is utilized on the engine exhaust nozzles to reduce radar and IR signatures, and a greater amount of wide-band structural RAM is used on the wing edges. The interesting shape of the radome on the F-22 reflects radar signals at all frequencies except the precise wavelengths emitted from the F-22. This can be attributed to the radome's low bandpass type.


www.globalsecurity.org...

read under infrared radiation in the globalsecurity link.


s one can obviously perceive, the IR signature cannot be eliminated, at the best only reduced. Flying at lower speeds, and using surface paints which have a similar IR reflectance to the background is liable to reduce emissions from the aircraft's skin. Emissions from hot parts of the engine can be screened off by parts of the airframe. The plume temperature may be reduced by mixing in further cool air, thus assisting in reducing the temperature of the tailpipe region. The key to success in suppressing an aircraft's signature lies in shifting its IR emissions into regions (wavelengths) which are more heavily attenuated by the atmosphere (as things are, the near IR is best transmitted in three 'windows', the 2.5, 4 and 10 micron bands), i.e. allowing them to fall outside of transmission windows, where they are more readily absorbed by C02 and water vapours. In this fashion, the heat emitted is far more difficult to detect, at long distances (a factor of growing importance, as the Soviets appear to be showing great interest in passive IR target acquisition systems).


www.ausairpower.net...



posted on Jul, 5 2006 @ 01:48 PM
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Originally posted by Aim64C
The F-22 is a stable design. Scale model RC aircraft of it can easily fly with no difficulties.


Your basing that on a model??

If you change the wing section, you change the Cp point, hence changing the static margin = stability.

Since no scale model is going supersonic, I'll happily bet that the wing sections are not the same as the F-22.


The F-22 is quicker to react in pitch than all the teen fighters, and is only slower in roll acceleration to the much smaller F-16. It won't achieve the pitch superiority over the F-16 without a reduced static margin or control authority.



posted on Jul, 5 2006 @ 01:54 PM
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Originally posted by Aim64C
There are a couple things that kill the thrust vectoring 'advantage'. First, during supersonic flight - the movements of the control surfaces are inverted.



Sorry, thats incorrect - during high transonic flight the trailing edge control surfaces may become inverted due to shock induced stalling when there is a higher pressure gradient [induced by a positive angle of attack].

After transistion to full supersonic flight, control functions much the same as before, although the mechanism for force [lift] creation has changed - the surface facing the flow [pressure surface] is more important than was the case in subsonic flow where lift comes mainly from the surface away from the flow [suction surface].


edit: I also have severe doubts over using leading edge slats for control in supersonic flight, due to the reason mentioned above - extending the slats will increase the droop of the leading edge, decreasing lift and inducing a nose down pitching moment - but when decelerating to subsonic speeds this effect will be reversed. Stability & Control engineers hate that [a large variation with conditions - and especially a reversal], even with FBW software its to be avoided at all costs, I know on the F-22 they went to great lengths with placement/size/canting of the 'vertical' tails to avoid similar instabilities in yaw at high AoA.

[edit on 5-7-2006 by kilcoo316]



posted on Jul, 5 2006 @ 02:38 PM
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First off - the F-22's IR emissions are well within detection thresholds. They are low enough to reduce IR searching mechanisms (such as using ground based IR search devices rather than radar) - or to nullify long-range IR seeking missiles - but short ranged missiles - Dogfighting missiles - will have no problem with the Raptor.

Although the materials involved in the development of the Raptor are very effective at reducing IR emissions - the fact of the matter is that the exhaust is spewed out of the plane before it can be distributed across the structure of the plane. Mixing the exhaust with airflow also works to an extent.

This is what the Raptor hype is all about - an FX7900 GTX graphics card in an AGP port - good materials - but not worth the hype in application. No numbers are ever given as to how effective using all of these expensive materials are - they're just slapped on and said "It makes it better."

My mistake on the control surfaces - It was a factoid from my dad several years ago - and it's quite probable he was mistaken.

The radar emissions of the raptor are quite a bit greater than that of the F-23. The shape of the plane, in an attempt to remain stable, does not keep leading and trailing edges parallel to each other - causing RCS lobe overlaps - which are lethal to a plane. RCS lobe overlaps are many times worse than reflections emitted by a material - to the point where the material a surface is made of does not matter - if the lobe overlaps - it's an area from which a radar can detect and destroy an aircraft.

The F-22 and F-23 both have advantages during supersonic flight. However, the YF-23 has a larger wingspan, larger wing surface area, a greater fuel capacity, and reduced drag. The reduction of drag reduces surface IR emissions and increases fuel efficiency - increased fuel capacity also means increased range/endurance.

The production line F-23 (which was already drafted up and ready to undergo initial production and testing had the YF-23 been selected) was going to have narrowed exhaust ducts (since STOLV was no longer necessary - although both aircraft are capable of it), an extended weapons bay - allowing for an additional 2 AMRAAMs - also increasing its mulitrole capability.

The F-23 was a more survivable aircraft than the F-22. Give me a single production-model F-23 and I'll take out an entire flight of 6 raptors ranging from maximum engagement range to a merger.

Of course - that will never happen - so my challenge means nothing.



posted on Jul, 5 2006 @ 03:08 PM
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I can definitely state for certain that neither the F-22 or YF-23 are STOVL capable, unless by 'STOLV' you meant something else?



posted on Jul, 5 2006 @ 05:54 PM
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Short takeoff and landing vehicle - yeah, both are capable of taking off and landing from a runway of those requirements. Although it would be stretching the performance of both aircraft to land within the requirements, as the reverse-thrusting was not implemented in either design.

However, STOLV was an original requirement of the project, which is why the YF-23 had rather large exhaust ducts - to facilitate the reverse-thrust mechanisms. However, the requirement was dropped, so the production model was drafted with much narrower ducts that would have further reduced RCS values and drag.

The production model also had some improvements in the airfoil of the aircraft that were learned from the prototypes. and as mentioned earlier - an extended fuselage that had an enlarged munitions bay that was designed to better enable multi-role capability.



posted on Jul, 5 2006 @ 11:52 PM
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I will be gone for a day and a half, so I will be posting a full evident report basing that my claims are correct with facts and sources after those days. Just hold on!

My post will be running over the time limit that I'm limited to now.



posted on Jul, 7 2006 @ 10:24 AM
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Those Russians are clever people IMO, they have the right idea.

Skip all the ruinous expense of actually making and operating a 4.5 or 5th gen fighter (this supposed new fighter has been so long coming it will be out of date if it ever sees the light of day) on anything approaching a large scale but keep the research up on maintaining the option of making leading edge stuff if it should ever be needed at some point.

It makes for a nicer and safer world IMO and by lowering their military spending priorities it means an aggressive, unstable and restless Russia is even less likely than it is anyway.
Pity for the rest of us that the US can't ease up on their military mania too.



posted on Jul, 7 2006 @ 10:33 AM
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Originally posted by Aim64C
Short takeoff and landing vehicle - - STOLV


Can you give me a source for that acronym as I have never heard it before? However when I googled 'STOLV' I got the reply 'did you mean STOVL?' and this is the acronym that I thought you were using, which stands for 'Short Take Off and Vertical Landing', which again, I absolutely guarantee is not a feature of either ATF design.

There were also search results for several forums where 'STOLV' was being discussed but in every single case they were talking about the F-35B and the Harrier and had misspelt STOVL - it must be a very common error.

Such as here for example;


google search for STOLV - Short Take Off and Landing Vehicle



[edit on 7-7-2006 by waynos]



posted on Jul, 8 2006 @ 06:36 AM
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In terms of the picture above showed, that advantageous of this PAK FA layout is:
1) Canards. according to basic aerodynamics, close set of foreward wing has more lift than normal layout.
2)The airframe was designed as a lift-airframe combined with canard will lead to a couple of separation vortex across throgh flaperon beside thrust nozzle while the fighter so high attack angle maneuver, so even over losing speed, this fighter still can be control at supersonic. remember, at supersonic, that vector thrust are almost no effective.
3)The vertical fin was set so wide that has more efficiency.
4)Almost all of leading edge of wing is parallel, so would have better low detective charator.
5)twin caudel vertebra could carry back-looking radar, the advantageous is obvious



posted on Jul, 8 2006 @ 08:29 PM
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That concept, I sure hope they doesn't even thought about build it up. I saw the pics of straight-wing version of Su-47 pictures and in some ways, it have comparsions with F-22 Raptors. I'm seeing the great competiton coming soon between Raptors and Berkuts. Its a way to go design, you guys will like it. You can find on google and click "image" and type Pak Fa and you will recongize it with few other concepts.



posted on Jul, 8 2006 @ 10:28 PM
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Originally posted by sminkeypinkey
Pity for the rest of us that the US can't ease up on their military mania too.


America spends around 4% of her GDP on defences, I would hardly call that "military mania"

It just happens that 4% of 13 trillion is a lot of cash.




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