Sukhoi PAK FA

hit&run

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Some where i read that this plane has Artificial intelligence equivalent to human. Is it true can some one elaborate on this. What i have studied that humans are still not able to develop very basic intelligence artificially.
 

ppgj

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looking at the LERX and short take off capability and a natural high lift it obtains because of large delta wing, it seems, PAKFA down the line will have a naval variant - speculative though at present.
 

ppgj

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Some where i read that this plane has Artificial intelligence equivalent to human. Is it true can some one elaborate on this. What i have studied that humans are still not able to develop very basic intelligence artificially.
i guess, they mean to say the system's sensors are so advanced, that - they come close to what can be humanly possible.
 

p2prada

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Some where i read that this plane has Artificial intelligence equivalent to human. Is it true can some one elaborate on this. What i have studied that humans are still not able to develop very basic intelligence artificially.
They mean to say their best computers and softwares are in this plane. None of that Artificial Intelligence garbage.
 

Anshu Attri

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http://www.ausairpower.net/APA-NOTAM-130210-1.html

In his address to the Nation, the US Forces Commander in Chief declared:

“Well I do not accept second-place for the United States of America.”
State of the Union Address, January 2010
When it comes to America's defense policy and her ability to maintain air superiority if not air dominance, the US Secretary of Defense has obviously not read the memo. Thus, the challenges for this Presidential declaration of intent are twofold.

Firstly, the current anti-access and area denial capabilities of non-American origin that already exist in the marketplace will relegate the United States of America to second place in the air power stakes.
Machines like the Russian Sukhoi Su-35S Flanker1, which is specifically intended for export and is not ‘your Father’s Flanker’, assure this outcome, particularly when interoperating with the contemporary integrated air defense systems (IADS), equipped with S-300PMU2 Favorit / S-400 Triumf Surface to Air Missiles.
Secondly, with America becoming its own peer threat2 through naive if not ill considered and misled decisions like shutting down F-22A Raptor production at 187 aircraft, and putting all of its tactical air needs into one basket - the just so flawed JSF Program3 – then not accepting second place becomes a logic euphemism for saying that third and fourth place, or no place at all, are okay.

As to why the term JSF actually stands for ‘just-so-flawed’ and ‘just-so-failed’, one only has to study the form guide to see the knobble-ing by artisans of 'a total indifference to reality'4 at work and how the teachings of conventional wisdom5 have been ignored.

For instance, the JSF has about as much chance of being a Fifth Generation Fighter6 as the present Commander in Chief has of becoming the 46th President of the United States of America. Just as the US Constitution and US Law preclude the latter, there are the Laws of Engineering, Physics, Commerce and Common Sense that prohibit the JSF from ever being anything other than the misadventure it is.

This misadventure is now replete with spiraling cost increases, the figures looking like international telephone numbers on a cost base that resembles the galactic equivalent thereof; with almost weekly announcements of further schedule delays in plans that seem to be forever changing; and, failures to deliver on promises, particularly those marketed to the Australian people by senior US and Australian defense officials back in 2001/02.

Just who was it who said the JSF was affordable at “around forty million dollars per aircraft”?

However, these traits of misadventure are all now moot and for one simple, undeniable and self evident fact.

The advent of the Russian PAK-FA T-507 , the next true Fifth Generation Fighter, designed specifically to occupy the same territory as the F-22A Raptor and its far less capable siblings, the JSFs, has set in stone what many believe was achieved with the coming of its predecessor, the Sukhoi Su-35S Flanker.

That is, the JSF has now been made totally irrelevant, strategically as well as tactically, and will not be competitive, either in the air or in the marketplace.

The long evolving design pedigree of the PAK-FA T-50 has resulted in an aircraft that will be able to do things that no Western design is capable of doing. This is a game changer, a sure fire certainty in the air power stakes.

The only American aircraft that has any credible chance of being made to be competitive is the F-22A Raptor.

However, that chap who has yet to read the memo, has yet to also realize the error of his ways, though the fog would appear to be lifting and the painful truth that comes from realizing you have been duped is starting to make its presence felt.

Now, the simple question is: Which would be the more costly economically as well as politically – defending the fact that a mistake has been made and needs to be corrected, quickly, that is, “evidence based policy making” as our Prime Minister is apt to say; or, trying to defend your nation with something that can’t even make it to first base, let alone into second place?

Air Power Australia is built on the great Australian heritage of punching above one’s weight while looking out and caring for one’s friends (a.k.a. “mate-ship”) and the earnest Australian belief in ‘a fair go’, as well as calling things as we see them, a.k.a. ‘straight talking’.

In keeping with these traditions, everyone should have the chance to admit their mistakes; then given the opportunity to fix them.

So it should be for the US Secretary of Defence and the just so flawed JSF Program. However, if Bob Gates does not have the wisdom and grit to do what is right and what is best, then the Commander-in-Chief should take over stewardship of this misadventure and scratch this knobbled and hobbled nag and all the rent seeking jockeys and punters and dopers that have sat astride it for so long.

As the Hon Robert Gates said recently when he sacked the very honest, honorable and straight talking MajGen David ‘Duncan’ Heinz, “. . when things go wrong, people will be held accountable”.
 

Anshu Attri

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http://www.defpro.com/daily/details/506/

Part 2 of a comprehensive overview on Sukhoi’s 5th generation fighter.

06:53 GMT, February 11, 2010 On 29 January 2010, the Sukhoi PAK-FA (Perspektivnyi Aviatsionnyi Kompleks Frontovoi Aviatsy, literally "Future Front line Aircraft System"), which could variously be described as a technology demonstrator, the first prototype of the future T-50 fighter, or an intermediate step between the two, took to the air for the first time from the freezing runway of Dzemgi Air Force Base (shared with the KnAAPO plant) at Komsomolsk-on-Amur in the Russian Far East Siberia (see also http://www.defpro.com/daily/details/497/). A fundamental step has at last been accomplished in the development of the long-expected Russian response to the American F-22 RAPTOR air dominance fighter.

(Part one of the article can be viewed here: http://www.defpro.com/daily/details/505/)


Airframe

The aerodynamic configuration of the PAK-FA maintains a vague reference to the Su-27 as regards the fuselage and the location of the engines, which are installed in widely separated nacelles forming a tunnel with the flat bottom of the fuselage. The general planform is a tailed delta, similar to the F-22, with the all-moving horizontal tailplanes close-coupled and on the same plane to the wing without any gap. The twin vertical surfaces, canted outward by perhaps 25°, are also all-moving. This solution has been used rarely in recent times; in particular the ill-fated Northrop YF-23 had a pair of all-moving butterfly tailplanes. The all-moving verticals however had been fairly used in supersonic designs dating back to the late 1950s or 60s, in particular the SR-71 which used a pair of all-moving verticals canted inward to reduce the induced roll moment when the surfaces were rotated, and most of the North American design of the period - the RA-5C VIGILANTE, its contemporary YF-107 and the unique XB-70 - as well as the British BAC TSR 2 used a similar solution. In the PAK FA design, their reason d’être arguably consists in enabling the smallest possible vertical surfaces for the sake of reduced radar signature and supercruise drag, while at the same time also maintaining (in combination with the 3D TVC nozzles) excellent manoeuvrability.

The underfuselage tunnel between the engine nacelles contributes significantly to the overall aerodynamic lift generation, just as in the Su-27 and MiG-29 as well as in the F-14 - arguably the real originator of the “centreplane lift” concept. This lift is added to that provided by the large wing and should enable excellent manoeuvrability even at high altitude - a potential advantage of the F-22 and now the PAK FA over all their rivals. The widely separated engines also offer much better survivability in the event of battle damage or accidental fire/explosion.

The fuselage sides have marked “chines”, again like the F-22 and its unfortunate competitor, the YF-23. This shaping can be assumed both to contribute toward reducing radar reflectivity and to develop, at high angles of attack, favourable lift-enhancing vortexes flowing above the inner wing upper surface just above the engine nacelles. The wing has dropping leading edges providing for a variable camber airfoil and separate flaps and ailerons, these latter contributing towards enhanced TO/landing performance (this should anyway be very good, given the huge lift generated by the aircraft configuration as a whole). The inner part of the wing leading edges is stepped longitudinally with a much longer chord which blends forming, in part, the engine nacelles’ upper “lips” and then merging into the fuselage to enhance the lift generating characteristics of the overall aircraft configuration, somewhat akin to a lifting body. Possibly for this reason, but also to ease a smooth airflow into the engines at very high angle of attack, the upper intake projecting false “lips” appear to be hinged parallel to the sweep real intake lips, thus providing a variable camber like the wing leading edge. In this way, the upper surface of the air intake contributes to overall lift generation. It is also possible that the movements of these peculiar elements, when linked to the full authority digital flight control system, could contribute in some way to the aircraft’s longitudinal control, acting like a third control surface (in line with the Sukhoi tradition as exemplified in the three-surfaces Su-30MKI). It seem however clear that the “lips” cannot move as fully independent control surfaces, due to their primary role in ensuring a correct airflow to the engines.

The possible rationale behind the fuselage “chines” and wing strakes could be to generate two vortexes over each wing upper surface, thus enhancing lift (via more diffused vortex lift) at high angle of attack (AoA). In particular, the two inner vortexes (those generated by the fuselage “chines”) would energise the airflow over the inner wing upper surface blending with the fuselage above the engine nacelles. The two outer vortexes (those generated from the wing strakes outboard the intakes lips) would transfer their kinematic energy to the upper outer panel wing airflow. Furthermore, given the expected path of such latter vortexes, they would also interact with the upper airflow over the all-moving horizontal tailplanes - thus replicating the superior longitudinal control provided in the Su-27 by its peculiarly located slab tailplanes.*

Summing up, lift appears to be generated by following elements, working in a synergic way:

• Wing outer panels (outside the engine nacelles) with dropping leading edges (variable camber airfoil);
• Engine nacelles upper surface blended with outer wing panels and fuselage with dropping intake upper false lips/leading edges (variable camber);
• Fuselage tunnel between the engine nacelles;
• Vortexes generated from the front fuselage “chines“, enhancing the engine nacelles upper surface lift and possibly the all-moving verticals’ control authority at very high AoA;
• Vortexes generated by the wing strakes outboard the engine nacelles, enhancing the outer wing panels lift and possibly the all-moving horizontal tailplanes control authority at very high AoA.

The fuselage has the already mentioned flat bottom and a straight tapered upper part ending in a flat and somewhat smaller “sting” between the engine exhausts. The installation of a braking parachute in a bay in the upper part of the sting makes room for the rational introduction in the extreme tailcone of a wide-scanning ECM antenna or perhaps a rear hemisphere surveillance/tracking radar (experiments were carried out a few years ago on a modified Su-32FN). The second prototype, which was used for taxi trials on 23 January appears to have a different tail cone, for unclear reasons.

The rear fuselage beavertail appears wider than in the Su-27/-30 albeit with a similar layout, and should offer more freedom of movement to the multi-axis thrust vectoring control (TVC) exhaust nozzles which will most certainly be fitted to the engines of the T-50 (although their current presence on the PAK FA is not certain). This configuration with the widely exposed round engine exhaust nozzles is however detrimental in terms of rear-emisphere IR and radar signature.

The PAK FA is claimed by Sukhoi to offer “unprecedented small signatures in the radar, optical and infrared range”, and this is certainly true as regards Russian combat aircraft and quite possibly all existing non-American designs. At the same time, it is evident that the PAK FA has been designed with a close attention to stealth characteristics, but is not intended to be an uncompromising stealth aircraft à la F-22. When certain design features detrimental to low observability were deemed to be all-important, these were adopted nonetheless. It would be extremely interesting to watch the eventual results of this approach in terms of maintainability and operational availability, particularly in the light of the in-service experience so far with the F-22.

An element which maintains some similarity to the Su-27 family is the landing gear. All the members retract forward, easing the emergency extension which in this way can be accomplished simply by gravity and air pressure. The main tyres, again like the previous Sukhoi design, when retracted lays flat in bays partially above the air intakes and partially inside the thick wing root fairing born out from the air intake upper part and as a continuation of the sweep surface linking the fuselage side to the outer wing, running above the upper air intake lip.

The PAK FA appears to be built with a significant percentage of composites, including most of the wing, horizontal tailplanes and dropping intake lips skin, centre-forward engine nacelles, most of the fuselage skin and the doors of the weapons bays and landing gear bays. Metal parts seem to include the dropping wing and intake lips leading edges (with the exception of the inner sections where the conformal aerials are expected to be installed, and which should thus be built of dielectric material), the engine intakes and the wide fairings blending the outer wing panels to the fuselage. Press reports suggest a 75% (being weight) being made of titanium alloys and 20% by composites, which sounds plausible.


Powerplant

The planned engine for the T-50 is understood to be the new Saturn AL-41F, expected to offer about 17.5 tons of thrust in full afterburning mode and somewhere in the range of 12 tons in dry mode. The latter figure would comfortably enable supercruising (i.e., supersonic cruise flight without afterburner) at around Mach 1.5, thus in the same class as the F-22. The prototype/technology demonstrator now flying was expected to be powered by the Saturn 117S, a much improved version of the AL-31F intended for the Su-35 but still less powerful at 14.5 tons in full afterburning than the AL-41F. There however are some indications to suggest that the aircraft already has the new engines.

The engines are fed by two-dimensional raked air intakes with the upper lip generating an oblique shock wave favourable to dynamic pressure recovery in the supersonic regime, which for the PAK FA could approach Mach 2.3÷2.5. While in appearance of fixed geometry, it is possible that a variable-position upper ramp, to generate multiple oblique shocks is part of the system for a further better dynamic pressure recovery in the high supersonic speed regime.

The tight shape of the engine nacelles and the position of the ventral “venetian blind” auxiliary intakes seem to suggest that the PAK FA does not feature a serpentine air duct to the engine compressors, as typically adopted for low-RCS aircraft. It is possible that the Sukhoi designers have preferred to limit the compressors’ strong radar reflection by inserting a grill in front of them, while optimising the air intakes for higher max. speed and supercruise performance.

The engines are mounted with a slight forward convergence (some 3°). This, in twin-engine aircraft with conventional exhaust nozzles, would typically reduce thrust asymmetry in the event of an engine flame-out - although with the drawback of reduced controllability. Given however the installation of TVC nozzles, the choice of converging axis built into the nacelles could be the outcome of an aerodynamic local airflow optimisation due to interaction of all the aircraft elements.

A large fuel capacity in line with the previous Sukhoi fighters is certainly provided, let’s say in the order of 12,000 litres. A fully-retractable in-flight refuelling probe is installed on the left side of the fuselage in front of the windscreen.


Armament

The standard air-to-air armament is carried internally in two identical tandem weapon bays, which can be estimated at about 5m x 1.2-1.3m. The bays’ position inside the tunnel between the engine nacelles ensures a discrete opening of their doors at weapons launch, otherwise a drawback for a stealth aircraft. In addition, the doors have saw tooth-shaped edges to further reduce radar signature. The size of the bays can be assumed to allow internal carriage of eight R-77-class radar-guided AAMs with folding wings, i.e. the same figure as for the F-22.

Similar to American 5th generation types, for the “second/subsequent” days of war operations, four additional underwing hardpoints can be installed under the outer wing panels. However no wingtip store positions appear to have been foreseen. A dark area to the right side of the upper front fuselage under the cockpit betrays the installation, similarly to the Su-27, of a single cannon (a 30mm GSh-30-1?) for close combat engagements.


Avionics

The combat avionics of the T-50 has been under development for some time, and some elements will almost certainly be installed in the Su-35 interim fighter. The main sensor will be a Tikhomorov NIIP X-band radar with active AESA antenna, which was unveiled at the latest MAKS Air Show in August 2009. The 1m-dia. antenna contains some 1,500 solid stat transmit/receive modules by NPP Pulsar, which places it in the same class as the F-22’s APG-77. Tikhomorov claims an exceptional range of ~400km against a 1m² equivalent radar surface target. The radar entered bench testing in November 2008, and a flyable operational prototype will be completed by mid-2010.

In a very innovative development, the main X-band antenna will be supplemented by auxiliary L-band antennas installed in the wing inboard leading edges. In addition to the obvious IFF/SSR functions, this arrangement (which is also being offered for retrofit on the Su-27/-30 family as well as the Su-35), has a very clear anti-stealth search function. Most current stealth or semi-stealth designs - and most particularly the F-35 JSF, although not the F-22 - are optimised to reduce radar signature against X-band fire control radars as the main threat, and their low-observability features and shapings do not work as well against L-band radars. Of course, the lower the frequency the higher the wavelength the poorer the accuracy of distance and angular measurements, and thus even apart from excessive volume, weight, power and cooling requirements a fighter aircraft could not possibly rely on a main L-band system alone. However, the presence of the additional L-band antennas will provide an important early warning function against at least some low-observable targets, and it may also enable a “mini-AWACS” role. It is additionally conceivable that these antennas could also be used for the detection and disruption of sensors and digital communications systems operating in L-band, including e.g. the all-important JTIDS/MIDS/Link-16.

While the PAK FA has no functioning radar yet, it already sports the protruding head of an electro-optic IRST system in front and to the right of the cockpit’s windscreen. This will maintain the excellent mixed solution (radar/IRST) used in all modern Russian fighters, event tough the IRST seeker’s “ball” is at odds with the search for a reduced radar signature in the front emisphere. The decision to add the L-band antennas while maintaining the IRST reinforces the perception of the T-50 being mainly intended for air defence roles against intruding low-observable strike aircraft.


The Indian Factor

Back in early 2007, Russia and India reached an agreement to cooperate on a Fifth Generation Fighter Aircraft (FGFA) based on the PAK FA for the Indian Air Force. The programme is officially described as involving a 50-50% split as regards both financing and R&D activities, but it is nearly universally understood to rather cover a scheme, under which India will fund a substantial portion of the PAK FA’s development bill in exchange for access to the relevant technologies.

The Indian Air Force’s requirements do differ rather substantially from the Russian Air Force’s, and are reported to demand a twin-seat configuration as well as possibly a different wing and control surfaces. Hindustan Aeronautics Ltd is expected to become responsible for some 25% of the total development workload for the FGFA programme, involving modifying the PAK FA single-seater airframe to a twin-seater configuration as well as the mission computer, navigation system, cockpit displays and ECM dispensers. HAL will of course also take care of eventual series production of a tentatively planned total of some 200-250 aircraft.

Indian sources have ventured into suggesting that the FGFA could be in service by 2015, but this is quite obviously not feasible given that development has not yet started. A logical date would be well into the 2020s.


Conclusions

As a first tentative assessment and on the basis of the basis of the scarce information as currently available, the PAK FA (T-50-1?) looks like a mix of well-proven solutions from previous Sukhoi designs married to several new ideas, in particular as regards the still superior quality of Russian aerodynamic research.

It is also possible that the significant delay suffered in developing a Russian counterpart to the F-22 could have turned into a blessing in disguise, giving Sukhoi designers a period of reflexion to generate a well balanced design. This would relate in particular to the decision not to push for extreme low observability characteristics at the expense of everything else, including not only flight performance but also acquisition costs and most importantly maintenance requirements and thus operational availability.
 

Armand2REP

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What if you are making a deep penetration strike at some strategic target. I am assuming here that since the target is deep inside the enemy territory there might be operational SAM batteries & even airfields (may be slightly off the flight path). These may choose to engage after the aggressor has crossed them so that it does not have the option to turn back and run. This would be more important in an Indian perspective (India Vs Pak/China) as we don't have long range cruise missiles to do the job. If ballistic missiles are used I don't think the enemy is going to wait for it to detonate to see if it has a nuclear or non nuclear payload, we would probably have a nuclear war as soon as the missile launch is detected. So that option cannot be used.
If you plan on using PAK FA like an F-117 for penetration strikes with no support you will need a stand-off missile. The Russians aleady have the Kh-31 for ARMs and the Kh-59 for stand-off which I'm sure the PAK FA will carry. Launch your missiles and haul ass before anyone can catch you. That is how our fighters do it with Apache and Scalp. PAK FA will be able to get a bit closer with the internal bays and be able to escape with the super cruise. If you go the conventional route you will carry a strike package that includes SEAD and FastCAP. PAK FA can fill both those roles by blasting a hole in the defences on the ground and in the air. If India was counting on a strike plane that can fly into the heart of Chinese air defences alone and not get shot down, PAK FA is not it.
 

gambit

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couldn't understand please elaborate . if you have a decent RWR then how would you become a victim without knowing you are a victim??
You are missing the point. It does not matter if you have powerful engines or if you have a 'decent RWR' system. The point here is to avoid becoming a victim in the first place. The worst thing for any flyer is to know he has an aggressor in his after sector. It does not matter if the aggressor found him or not. The fact that he knows someone is looking for him forces him to reconsider his mission, as in how to achieve it in ways not in the original plan.

If you are in an ingress route to a target, you are the aggressor and your enemy is the victim. However, there are no guarantees these statuses will remain absolute. If enemy fighters managed to detect you they will attempt to prevent you from delivering your ordnance to their facilities, whatever those might be. In doing so, now it is YOU who are the victim. The enemy will deploy additional interceptors and/or missiles to either destroy you or deter you from your mission. As a victim who is determined to be the aggressor again, now you must take alternate routes to your target and this will consume additional fuel and require more time. The worst is that you may never reach your target. In short, it is NEVER a good thing to be a victim.

This is why you cannot ignore rear aspect RCS regardless of how good is your RWR system. If your RWR system detect seeking radars but there are no indicators that the enemy found you, you will be cautious but at least you know you are STILL hidden from his radar thanks to your low rear aspect RCS. You are a victim only if you are compelled to take actions that deviate from your original plan. So you should have as low rear aspect RCS as possible, keep your RWR modern, be alert, have alternate plans, and hope you would not have to use those alternate plans thanks to your low rear aspect RCS.

Get it?
 

gambit

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How does rear aspect RCS matter to an agressor radar? Unless you have your ass facing their nose it won't even come up. You should already have control of the airspace behind you.
You cannot afford that certainty. Not even the US is willing to be that presumptuous.
 

gambit

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By Itar-Tass World Service writer Lyudmila Alexandrova

The plane's shape makes it invisible in the optical, infra-red and traditional radar wave bands. The T-50 will have the capability to perform combat tasks in any weather round the clock and extra maneuverability. The minimum runway length requirement for take-off and landing is 300-400 meters.

I have no choice but to dismiss this columnist as nothing but an idiot. Basically...She is saying the aircraft is invisible to the naked eye.
 

planeman

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My guess at FGFA in light of T-50 layout. Basically just added a second seat slightly stepped to allow commonality with trainer version, and a deeper belly pan to allow carriage of KS-172 AAM. Click for larger view,

More on my blog in a few weeks. http://planeman-bluffersguide.blogspot.com/
 

SATISH

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You are missing the point. It does not matter if you have powerful engines or if you have a 'decent RWR' system. The point here is to avoid becoming a victim in the first place. The worst thing for any flyer is to know he has an aggressor in his after sector. It does not matter if the aggressor found him or not. The fact that he knows someone is looking for him forces him to reconsider his mission, as in how to achieve it in ways not in the original plan.

If you are in an ingress route to a target, you are the aggressor and your enemy is the victim. However, there are no guarantees these statuses will remain absolute. If enemy fighters managed to detect you they will attempt to prevent you from delivering your ordnance to their facilities, whatever those might be. In doing so, now it is YOU who are the victim. The enemy will deploy additional interceptors and/or missiles to either destroy you or deter you from your mission. As a victim who is determined to be the aggressor again, now you must take alternate routes to your target and this will consume additional fuel and require more time. The worst is that you may never reach your target. In short, it is NEVER a good thing to be a victim.

This is why you cannot ignore rear aspect RCS regardless of how good is your RWR system. If your RWR system detect seeking radars but there are no indicators that the enemy found you, you will be cautious but at least you know you are STILL hidden from his radar thanks to your low rear aspect RCS. You are a victim only if you are compelled to take actions that deviate from your original plan. So you should have as low rear aspect RCS as possible, keep your RWR modern, be alert, have alternate plans, and hope you would not have to use those alternate plans thanks to your low rear aspect RCS.

Get it?
Sir,
I have a question to ask...Sir, I dont have any doubt about the stealth capabilities of the F 22. But there is one question in my mind..If the F 22 radar locks onto the aircraft wont the aircraft be warned by the RWR as soon as the lock is achieved? Once the pilot knows this wont he and his WSO start working on deploying the counter-measures and jamming the missile radar? How well is the AIM 120D onboard Radar protected from Jamming? if the Missile misses target then wont it lead to a WW type of merge forcing the F 22 into a dogfight? How well is the performance of the F22 compared to its adversaries in the SU/MiG/J 10/JF 17 when it comes to aerodynamics? I guess there are lots of questions...Kindly request your assistance here sir.
 

Armand2REP

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You cannot afford that certainty. Not even the US is willing to be that presumptuous.
The PAK FA has a rear radar with range enough to use the R-77, it is pretty well covered from the conventional threats. With the supercruise they won't be likely to catch up to it anyway. If they use it as a strike fighter as IAF plans, there will be Su-30MKIs with powerful radars providing FastCAP anyway. I doubt its "fat ass" is big enough to give it away at more than 30km.
 

planeman

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Sir,
I have a question to ask...Sir, I dont have any doubt about the stealth capabilities of the F 22. But there is one question in my mind..If the F 22 radar locks onto the aircraft wont the aircraft be warned by the RWR as soon as the lock is achieved? Once the pilot knows this wont he and his WSO start working on deploying the counter-measures and jamming the missile radar? How well is the AIM 120D onboard Radar protected from Jamming? if the Missile misses target then wont it lead to a WW type of merge forcing the F 22 into a dogfight? How well is the performance of the F22 compared to its adversaries in the SU/MiG/J 10/JF 17 when it comes to aerodynamics? I guess there are lots of questions...Kindly request your assistance here sir.
The latest radars like on the F-22 (and presumably PAK-FA) are designed to not let the enemy know if they have been locked onto or not. Older radar systems had different modes for search and track so opponent could tell whether they were being targetted or not, less so now.

F-22 is very credible in close, especially if it receives HMS and AIM-9X which seems to be odds-on before PAK-FA enters meaningful service. PAK-FA may be better with more control surfaces and 3-D TVC, but it's likely to be close enough that the well trained American pilots can fly their planes to optimise their chances.
 

notinlove

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You are missing the point. It does not matter if you have powerful engines or if you have a 'decent RWR' system. The point here is to avoid becoming a victim in the first place. The worst thing for any flyer is to know he has an aggressor in his after sector. It does not matter if the aggressor found him or not. The fact that he knows someone is looking for him forces him to reconsider his mission, as in how to achieve it in ways not in the original plan.

If you are in an ingress route to a target, you are the aggressor and your enemy is the victim. However, there are no guarantees these statuses will remain absolute. If enemy fighters managed to detect you they will attempt to prevent you from delivering your ordnance to their facilities, whatever those might be. In doing so, now it is YOU who are the victim. The enemy will deploy additional interceptors and/or missiles to either destroy you or deter you from your mission. As a victim who is determined to be the aggressor again, now you must take alternate routes to your target and this will consume additional fuel and require more time. The worst is that you may never reach your target. In short, it is NEVER a good thing to be a victim.

This is why you cannot ignore rear aspect RCS regardless of how good is your RWR system. If your RWR system detect seeking radars but there are no indicators that the enemy found you, you will be cautious but at least you know you are STILL hidden from his radar thanks to your low rear aspect RCS. You are a victim only if you are compelled to take actions that deviate from your original plan. So you should have as low rear aspect RCS as possible, keep your RWR modern, be alert, have alternate plans, and hope you would not have to use those alternate plans thanks to your low rear aspect RCS.

Get it?
If i am the aggressor then the enemy fighters and sam sites would be in my forward sector and not aft sector. and as armand said before , i would be having my ass covered with other fighters providing fastCAP.i think we are talking about different missions here, i am talking about Prilim SEAD missions here and i suppose you are talking about Deep strike missions.

Moreover , the point of contention was

Being a victim without knowing you're a victim
You'll atleast know when you have been detected.
 

gambit

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If i am the aggressor then the enemy fighters and sam sites would be in my forward sector and not aft sector.
Wrong...Seriously wrong...And is indicative of gross naivete. The ideal situation for any hunter is to be BEHIND the prey, which would be YOU. Interceptors, be it manned aircrafts or missiles, could be from your sides, or if possible, SAM launchers would allow you to pass so your large rear aspect RCS and IR returns would provide seeker heads direction.

and as armand said before , i would be having my ass covered with other fighters providing fastCAP.
Again...You and your friend are being awfully assured of your air supremacy.

i think we are talking about different missions here, i am talking about Prilim SEAD missions here and i suppose you are talking about Deep strike missions.
It does not matter.

Moreover , the point of contention was

Being a victim without knowing you're a victim
You'll atleast know when you have been detected.
Against an LPI radar, odds are very good that you will be a victim without knowing you are already a victim. You need to check up on pilot testimonies on why they always 'check six'.
 

gambit

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If the F 22 radar locks onto the aircraft wont the aircraft be warned by the RWR as soon as the lock is achieved? Once the pilot knows this wont he and his WSO start working on deploying the counter-measures and jamming the missile radar?
You are treading into Low Probability of Intercept (LPI) radar mode. So here it goes...

NOTHING is invisible to radar. We need to get that fact out of the way. The US have never claimed our 'stealth' aircrafts are 'invisible'. Any antenna, and this include the popular image of a rotating dish radar antenna, coupled with sensitive enough receiver hardware, can pick up cosmic background radiation. But this is not what we want. Other things that we do not want to DISPLAY are water, earth, clouds, insect swarms, flocks of birds, storm mass, and many other natural objects. So what we do is classify the radar return signatures for these items as 'clutter' and do not display them. This is called 'clutter filtering' or the 'clutter region'. Remember...We do detect them, we just do not want to DISPLAY them.

What an LPI radar mode does is to transmit a pulse that attempt to mimick all the characteristics of these 'clutter' items. The radar warning receiver (RWR) set is basically the receiver portion of the total radar system: transmitter and receiver. It contain all the 'clutter' type signals and will not warn the pilot, after all, why would you want to warn the pilot that there is cosmic background radiation? Birds and insects do not transmit, but the universe is filled with noise and all around us are stray radio and television signals. We do not want to warn the pilot of these items. So what the RWR system does is to search for signals that contains characteristics of a seeking radar. Radio and television signals that bounces off the layers of the atmosphere have different signal characteristics that we inject into such as high and rapid amplitude and frequency modulations to carry information. Radar transmissions are less complex but they do have distinct characteristics.

However, if a radar transmission is low powered enough it may be able to hide in the clutter region despite having distinct characteristics. Background noise do have occasional spikes that are above the clutter threshold but in order for the RWR system to classify it as a legitimate radar seeker transmission, there must be some level of constancy over time. This detection and classification is called 'probability of intercept'. The word 'intercept' here is meant to denote a recognition that the system is being scanned by an unknown radar. If the transmission is in the megawatt range then certainly it will have a highest level of 'probability of intercept', correct? So what an LPI capable radar system will do is to transmit a pulse in a freq that will spike just barely above the clutter region, then jump to another freq, then another and so on. It must remember the exact sequence of these jumps. This is called 'frequency agility' and is often used to resist ECM. But freq agility is equally important in LPI operation in the sense that agility is necessary to avoid recognition. The important thing to remember here is the difference between 'detection' and 'recognition'. The RWR system may or may not detect these low power pulses, but even if it does detect them, the freq spread is sufficiently wide enough that the RWR system would classify them as background noise spikes, hence 'low probability' of recognition or 'intercept' -- Low Probability of Intercept mode.

Any radar can be modified to have LPI mode, provided the level of technological sophistication is available. But the best LPI radar is an Active Elect Scan Array radar system. The F-22 has an AESA system. An antenna is a physical structure that contain the array. There is an AESA technique called 'subarray partitioning' where a single antenna can turn into multiple arrays.

http://www.faqs.org/patents/app/20080204350
The forward housing may be designed for redundancy. For example, each antenna subassembly 102 assembly may contain four separate, individual subarrays. In such an embodiment, each subarray is functionally independent of every other subarray. If one subarray fails, the other subarrays continue functioning. With such an embodiment, a technician may be able to delay needing to perform repairs on the individual antenna 102.

There is one large array in 'a' and there are nine subarrays in 'c'. Can you see that? Subarray partitioning is possible ONLY with an AESA system, not a PESA system. With sophisticated array partitioning and choreography software, and they are top secret, an LPI radar can transmit low power pulses in different freqs AT THE SAME TIME or in various sequences that will not be any more suspicious than background noise spikes, giving the F-22 greater assurances of its target information than any other type of LPI capable systems out there. The key is the array partitioning and choreography software. With the AESA and LPI combination, the victim will be so without him knowing he is a victim with his RWR of little help.

How well is the AIM 120D onboard Radar protected from Jamming?
The missile's own radar could be inactive as long as the F-22 is able to provide guidance from the mentioned AESA/LPI radar system. Once the missile is close enough its radar will go active to provide boresight seeking. Future versions will have the missile equipped with its own AESA/LPI radar. The F-22's larger AESA is already extremely resistant to ECM.

if the Missile misses target then wont it lead to a WW type of merge forcing the F 22 into a dogfight? How well is the performance of the F22 compared to its adversaries in the SU/MiG/J 10/JF 17 when it comes to aerodynamics? I guess there are lots of questions...Kindly request your assistance here sir.
The F-22 will be dominant in that regime as well and I do not place high value on 3D thrust vectoring or that airshow 'cobra' maneuver.
 
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notinlove

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Wrong...Seriously wrong...And is indicative of gross naivete. The ideal situation for any hunter is to be BEHIND the prey, which would be YOU. Interceptors, be it manned aircrafts or missiles, could be from your sides, or if possible, SAM launchers would allow you to pass so your large rear aspect RCS and IR returns would provide seeker heads direction.
Why would a SAM operator take such a risk?

gainst an LPI radar, odds are very good that you will be a victim without knowing you are already a victim. You need to check up on pilot testimonies on why they always 'check six'.
Agreed, an LPI radar does decrease it to an extent, legacy RWR systems would be rendered quite useless against an agile beam in search mode.

if you have any data regarding the performance of modern sensor systems like ALR-94 against an AESA do share it
TIA.
 

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