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International Military News and Discussion

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International Military News and Discussion
#41
An interesting analysis on PAk-FA ( via keypubs ) link



Quote:A week past when the PAK·FA flew, it is the time to summarize some information we collected before till the some of huge pix showing PAK·FA released nowadays.



While the PAK·FA unveiled, it still surprised most of aircraft fans, although seemed they saw it somewhere or somewhen. Why, because the PAK·FA does have some advantages hidden behind the attractions from its appearance.



The first impressive character is its CARET inlet.

CARET inlet was not innovatively used by PAK·FA but S.H.E/F, nevertheless, the basic principle of CARET inlet is wave-ride, Russian used it better than American on PAK·FA, that's why we saw they transversely set the rectangular section of CARET inlet. Review: the longer the horizontal wedged edge, the more lift will be.



Second, movable LERX upon the CARET inlet.

This is the first time we saw a movable LERX was used on a true jetfighter, we remember Indian HAL LCA Tejas was planned it but that was merely a plan.

Is this only a movable LERX? I think it also is a vortex aileron, not a flap, it is capable to up-deflect, so it contains canard function too. We say it is a movable LERX because the angle of swept is really large enough to be a LERX. A large angle of swept edge cause vortex roll from down site to the up surface, however, when being slight AoA, this swept angle is too large to keep the pressure under the LERX so give a movable leading edge down deflect for works.

Then if you watch carefully, the LERX was up deflecting when PAK·FA tends to take-off, so the effect of this period factually is a canard alike.

Moreover, the movable LERX is a easy way to regulate the swept angle of shock wave produced by edge of CARET inlet whereas F-22 made it bypass door which was a hard method.



Thirdly, all-moving dorsal fins.

The earliest all-moving vertical tail we can remember was A-5 Vigilant used. The most strongest memory the A-5 gave me was wide-side setting engine nacelle, which also brought a commodious weapon bay to the A-5 Vigilant. Following the A-5 was F-14,the favorable jetfighter to the most military fans. The Tomcat set duel-fin. Now it is PAK·FA turn, that duel-fin is not enough to control such wide airframe, plus, too many tough maneuver are waiting for it to do, then we saw a couple of all-moving vertical tail with considerably small area for reducing weight.

Compare to the ATF from YF-22 to F-22's junk-like tail fin, this all-moving vertical-wing gives PAK·FA amount of advantages: reducing weigh; reducing RCS, more stability in High-maneuver, more controllability for yaw and spin.



Fourthly, omnidirectionanl vectoring thrust.

The nozzle F-22 like is worked for doable TVC at that time because airtight of movable workpiece in high temp pressure was hard to be circular shape, not like somebody dreamed for IR stealth。The rectangle nozzle was farfetched as stealth nozzle because of the exhaust gap appeared on F-117。 Yes, if L/W ratio approach the exhaust gap like F-117, you do gained IR reduced, but we say the nozzle on F-22 is a rectangle nozzle rather than a gap on F-117。But now, F-22 lost its capability of horizontal vectoring thrust.

Obviously, the OVT bring an ability of omni-maneuverability to do "helicopter" maneuver without loop previously.



Fifthly, YF-23 like back

The acr-shaped slope at up-surface will be a lift coming according the principle of Bernoulli. YF-23's design used it well but overrun. PAK·FA inherited it with slight humpback not only got drag reduced also obtained an additioanl lift from fuselage.



Last but not least

A relatively big angle for swept wing.

We know area ratio used for capability of transonic and supersonic good, but nobody noticed waspish design works for transonic good whereas there is another way design airframe like arrow same as Eurofighter Typhoon did, also is an excellent way for supersonic fly. The principle here is, the more time or position of shockwave occur you delay, the more drag could be decreased. For the PAK·FA, a high-swept wing will works for a real supercruise not like F-22 doing supersonic although without afterburner but still with range reduced compare to none-supersonic fly.
  Reply
#42
Looking at the small all movable Vertical Stabilizer and 3D TVC , my thinking is some advanced variant of PAK-FA will do away with VS and will only rely on 3D TVC once the engine and TVC has proven to work and is fail proof.



This will make the PAK-FA highly unstable giving it greater maneuverability and reduce its RCS even further.



What do you think on this Arun ?
  Reply
#43
[quote name='Austin' date='08 February 2010 - 07:58 AM' timestamp='1265633438' post='103993']

Looking at the small all movable Vertical Stabilizer and 3D TVC , my thinking is some advanced variant of PAK-FA will do away with VS and will only rely on 3D TVC once the engine and TVC has proven to work and is fail proof.



This will make the PAK-FA highly unstable giving it greater maneuverability and reduce its RCS even further.



What do you think on this Arun ?

[/quote]



Might the same thought and application add fuel to the indian AMCA? May be this is how the no stabilizer version of MCA appeared after validating MKI?



the experience that is cashed using FGFA is of invaluable sort that can enhance the scope of realisation of indian 5th gen with some one add-on and optimization in terms of technology.
  Reply
#44
[quote name='Austin' date='08 February 2010 - 06:28 PM' timestamp='1265633438' post='103993']

Looking at the small all movable Vertical Stabilizer and 3D TVC , my thinking is some advanced variant of PAK-FA will do away with VS and will only rely on 3D TVC once the engine and TVC has proven to work and is fail proof.



This will make the PAK-FA highly unstable giving it greater maneuverability and reduce its RCS even further.



What do you think on this Arun ?

[/quote]



Quite possible. I am nor sure quantitatively how much role the tail plays at supersonic speeds. As an aside the tail as it is now a a very light (composite material) structure, thus not such a weight or stealth issue. The only issue (a minor one) is its drag at supersonic regime



Another interesting possibility could be merging tail with elevator to make it a slightly V tail.
  Reply
#45
^^^ Arun wouldnt an aircraft without VS will be very highly unstable and hence far more maneuverable than any present manned fighter ?



some info on PAK-FA ( Russian Video )



[media]http://www.youtube.com/watch?v=J3uaS7pRGqE[/media]
  Reply
#46
[quote name='Austin' date='09 February 2010 - 09:23 PM' timestamp='1265730319' post='104042']

^^^ Arun wouldnt an aircraft without VS will be very highly unstable and hence far more maneuverable than any present manned fighter ?[/quote]

VS is for yaw stabelity. Not sure of aerodynamic maneuvering using yaw as a maneuvering advantage (I can only see that happen at very slow (sub stall) speed). I have not yet seen a craft designed for high yaw aerodynamic maneuver. In this case there is a side looking X band radar, teh missile lock and launch can be achieved without yawing the airframe.



Interesting video w.r.t. radars and sensors. "L band" is on leading edge of main wing.
  Reply
#47
VS is for yaw stabelity





Its a rudder that controls the yaw whereas the vertical stabliser controls the side slip.
  Reply
#48
Sukhoi PAK FA: First Observations Part 1 and 2

By Sergio Coniglio



[Image: f31e3343673b08b21f28d668752e0412fa205862_big.jpg]



06:51 GMT, February 10, 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.





The aircraft, with Sukhoi test pilot Sergey Bogdan in the cockpit, remained airborne for 47 minutes, enabling an initial evaluation of its controllability, engine performance and primary systems operation, including retraction and extraction of the landing gear. “The aircraft performed excellently at all flight-test points. It is easy and comfortable to pilot”, said Sergey Bogdan.



“Today we’ve embarked on an extensive flight test programme of the 5th generation fighter,” commented Mikhail Pogosyan, Sukhoi Company Director General. “This is a great success of both Russian science and design school. This achievement rests upon a cooperation team comprised of more than a hundred of our suppliers and strategic partners. The PAK FA programme advances Russian aeronautics together with allied industries to an entirely new technological level. These aircraft, together with upgraded 4th generation fighters will define Russian Air Force potential for the next decades.



“Sukhoi plans to further elaborate on the PAK FA programme which will involve our Indian partners”, Mr Pogosyan added. “I am strongly convinced that our joint project will excel its Western rivals in cost-effectiveness and will not only allow strengthening the defence power of Russian and Indian Air Forces, but also gain a significant share of the world market”.



Some Russian sources have suggested that the T-50 will enter service in 2015 (e.g. Russian 5th-generation fighter deliveries delayed until 2015), but this is but wishful thinking. Only another flyable PAK FA prototype and a ground test item exist thus far, while Sukhoi has indicated they will complete five prototypes for initial testing. These are scheduled for completion in 2011-12, with the company expecting to then produce an initial batch of pre-series aircraft for operational trials by 2015. A more credible projected IOC date for the T-50 would thus be towards the end of the decade - i.e. some 12-15 years after the F-22. Such a delay would be roughly in line when not with the scientific and technological potential of the Russian aerospace industry, then certainly with the Russian MoD’s financial muscle and the irredeemable time loss of the “black years” following the collapse of the USSR. There are persistent rumours of the PAK FA programme being largely financed directly by Sukhoi (some 75%, with the remaining 25% being provided by India), and in any case it is quite obvious that it could only progress thanks to the substantial revenues from export sales of Su-27/-30s.



Much has already been written and speculated about this first Russian 5th combat aircraft, but virtually nothing is known for certain. The few photos and the couple of videos documenting the first flight are all that is available for a first assessment of the aircraft’s characteristics, analysing its overall external configuration and trying to deduct the Russian Air Force’s requirements on which the PAK FA design can be assumed to be tailored.



Operational Considerations



As expected, the twin-engine PAK FA is a large aircraft, with roughly the same physical size and weight class as the Su-27/-30 family it is aimed to replace. The aircraft’s general configuration strongly suggests a design optimised primarily for the air superiority role, even though the T-50 will almost certainly eventually go along the same road as the Su-27 and evolve into a very capable multirole fighter-bomber. This emphasis on air-to-air combat is arguably due to both the Russian Air Force perceiving its main roles in a very different way than the USAF, and the fact that the Service’s deep strike requirements are satisfactorily covered by the very capable (although admittedly not stealthy) Su-34s currently being delivered.



Even though it is nearly automatic to think of the PAK FA/T-50 in terms of a direct confrontation vs. the F-22, and this may indeed have been the original goal when the programme was first launched in the late 1980s, in the current global strategic scenario it is perhaps more likely that the Russians are rather interested in maintaining an air superiority edge over China’s current J-11s/SU-27s/-30s and future J-12. Also, the expected future worldwide usage of the F-35 JSF attack aircraft with its low observability qualities requires an interceptor capable to deal with this peculiar threat.



Further considerations can be done as regards the expected future place of the T-50 in the Russian Air Force’s inventory, and thus the overall combat aircraft programmes in Russia. When first information on the PAK FA project started to circulate, the programme was widely reported to be intended to replace both the Su-27 and the MiG-29, thus leading to a single-type combat aircraft fleet not unlike the French Air Force’s with its RAFALE. Whether this was purely “disinformacija”, or the Russians were actually planning in that direction back then, it is impossible to ascertain. The fact is, the T-50 given its size and expected avionics complexity will most definitely be an expensive aircraft both to procure and operate, and it is very difficult to imagine how the Russian Air Force could ever be able to acquire it in large number - not to mention the type, for all of Mr Pogosyan’s rosy forecast, having a rather limited potential export market. Current Western and unofficial Russian estimates are of a production run of some 250 aircraft for the Russian Air Force, and even this may prove to be overoptimistic. The combination of the T-50 as the spearhead of a tactical combat fleet composed largely by modernised 4th generation types, as suggested by Mr. Pogosyan, does certainly make sense - but it is rather doubtful whether it could really last for “decades”, apart from the Su-35. Also, the upgrade programmes currently underway do not involve the MiG-29.



Hence, and although the notion of the Russian MoD and national industry being able to sustain the simultaneous development and eventual procurement of t w o different 5th generation fighters does admittedly defy imagination, the eventual launch of a programme for a smaller and less expensive “lo” fighter in a “hi/lo” mix with the T-50 looks virtually compulsory. Failing to do so would leave the Russian Air Force critically crippled in quantitative terms, and would consign the future export market for “affordable” fighter aircraft to Western and Chinese designs.





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.
  Reply
#49
Quote:[url="http://www.defpro.com/daily/details/505/"]Sukhoi PAK FA: First Observations Part 1 and 2 [/url]

By Sergio Coniglio





Thanks Austin for this excellent and exhaustive report/analysis.

  Reply
#50
Finally the long awaited write up from APA is released



Assessing the Sukhoi PAK-FA



Sukhoi PAK-FA - Russia's Strategic ‘Game Changer’
  Reply
#51


[url="http://en.rian.ru/russia/20100215/157889612.html"]Russia, India to sign 5th-generation fighter deal in March[/url]







Quote: 15 Feb, 2010

Russia and India will sign the first contract on the manufacturing of a fifth-generation jet fighter in late February-early March, a Russian defense industry official said Monday.



"We expect a contract on the first stage of design, specifically the development of a technical design concept, to be signed in late February-early March," Alexander Fomin, first deputy head of the Federal Service for Military and Technical Cooperation, said.



He added that Russia and India were currently "at an active phase of negotiations" on manufacturing fifth-generation fighters.



It was not entirely clear whether Fomin was referring to Russia's prototype fifth-generation fighter, which has already made two test flights, or a new project. Nor did he indicate exactly what role India would play.



Russia has been developing its newest fighter since the 1990s. The current prototype, known as the T-50, was designed by the Sukhoi design bureau and built at a plant in Komsomolsk-on-Amur, in Russia's Far East.



It will be delivered to the Russian Air Force from 2015 onwards.



Russian officials have already hailed the fighter as "a unique warplane" that combines the capabilities of an air superiority fighter and attack aircraft.



NEW DELHI, February 15 (RIA Novosti)



  Reply
#52
Sukhoi's T-50 Ready To Fight with USA's F-22 Raptor



Quote:As suggested before, Т-50 resembles the American F-22 in appearance - aerodynamics is a stubborn thing. There are no miracles, and optimal shapes of promising machines always resemble each other – same nose dome, same tail unit. Under the fuselage you can clearly see missile-bay doors. The biggest difference between the American Raptor and T-50 is a more flattened shape of the latter.



“PAK FA goes far beyond just the new looks,” told Igor Korotchenko, a member of the Public Council of the Ministry of Defense to Izvestia. “It was designed with a number of innovative solutions related to new concealment technologies, new construction materials, artificial intelligence and element base.”



The All-Russian Research Institute for Aircraft Materials reported that T-50 is the first jet built with polymer carbon fiber reinforced plastic. This material is twice as light as aluminum and four to five times lighter than steel. New materials account for 70 percent of the jet’s surface. It is four times lighter than jets assembled with regular materials.
  Reply
#53
[url="http://www.openthemagazine.com/article/nation/india-s-ragtag-army"]India’s Ragtag Army[/url]
  Reply
#54
[Image: 317.jpg]



[Image: 316.jpg]
  Reply
#55
This is at ~ 175 Knots (330 KmpH) speed. When the AoA is high, one can see that tail fins see little velocity and its effectiveness plummet. Thrust vectoring engine thus are critical to provide lateral stability.
  Reply
#56
[url="http://www.dnaindia.com/world/report_russia-s-5th-generation-fighters-to-undergo-2000-test-flights_1354304"]Russia's 5th generation fighters to undergo 2,000 test flights[/url]

PTI Tuesday, March 2, 2010

Moscow: Russia's fifth generation all composite stealth fighter aircraft, in which India has a stake, would undergo over 2,000 test flights before its serial production commences, prime minister Vladimir Putin has said.



"Before the jet goes into production, it should complete over 2,000 test flights," Putin was quoted as saying by agencies at a meeting last night with the defence industry officials.



The T-50 technology demonstrator developed by Sukhoi Corporation would be Russia's answer to America's F-22 Raptor and J-35 fighters and is expected to be the next generation fighters for both India and Russia.



The T-50 made its maiden flight on January 29 and the standard flight tests programme of its three prototypes lasting couple of years would begin in April.



The Russians are keeping a veil of secrecy on the new fighter and have said that it would not take part in this year's Faranborough air show in UK. In his upcoming talks in New Delhi on March 12, Putin is expected to give a new fillip to the FGFA programme in which India's Hindustan Aeronautics Ltd and the fighters division of Russia's United AircraftCorporation (UAC) are 50-50 partners.



[color="#0000ff"]Although the airframe of the fighter would be of the Russian design it would be further developed with the contribution of Indian experts and engineers, who would provide composite materials for the hull and 'artificial intellect' for the FGFA.[/color]



According to sources Russia would begin the induction of single seater fighter beginning from 2015, [color="#0000ff"]while the twin seater jet designed exclusively for the IAF is expected to be inducted from 2017 onwards[/color].
  Reply
#57
[url="http://www.seattlepi.com/national/1152ap_us_us_pakistan.html"]US to share laser-guiding bomb kits with Pakistan[/url]
Quote:WASHINGTON -- The U.S. will deliver this month to Pakistan 1,000 sophisticated laser-guided bomb kits that would enable the government there to strike insurgent targets with more precision.



The arms sale suggests that U.S. officials are trying to deepen America's relationship with Pakistan and increase military cooperation. The U.S. has been trying to encourage Pakistan to take a tougher stand against Taliban forces operating within its borders.



Lt. Col. Jeffry Glenn, an Air Force spokesman, said Tuesday the U.S. had delivered 1,000 MK-82 bombs to Pakistan last month. This month's shipment of kits would enable Pakistan to use sophisticated laser technology to guide the bombs to specific targets.



Glenn said the U.S. also plans to provide Pakistan 18 new F-16 fighter jets by June.
  Reply
#58
[size="6"]Shifting Geopolitics Realigns Indian Relations[/size]

http://www.defensenews.com/story.php?i=4...=FEA&s=SPE



NEW DELHI - India has shifted back into a closer relationship with Russia as New Delhi perceives a growing threat from China while the U.S. Obama administration has focused on engaging traditional foe Pakistan to aid its Afghanistan campaign, defense analysts said.



While New Delhi signed a $2.1 billion contract with the United States to purchase six P-8I long-range maritime reconnaissance aircraft in January 2009, India and Russia closed the year by signing an agreement on nuclear cooperation and resolving the long-standing Admiral Gorshkov aircraft carrier dispute. India agreed to pay $1.2 billion above 2004's contracted price of $800 million for the ship.



The countries also finalized the joint production of a fifth-generation combat jet for $10 billion, and the Indian Navy has decided to buy additional MiG-29K aircraft from Russia worth about $1.2 billion.



India and Russia signed a nuclear cooperation agreement in December 2009 that offers India better terms than the Indo-U.S. nuclear cooperation agreement, which has yet to become operational, Indian officials said.



The Russians have offered a lifetime supply of fuel for reactors it would build in India and to transfer nuclear energy technology. India and the United States still have not concluded a crucial pact on reprocessing spent fuel, the primary hindrance to implementing a civilian nuclear cooperation deal signed in 2008, the officials said.





China is already making its presence felt in the Indian Ocean region, where it could come into conflict with Indian maritime interests, an Indian Navy official said. China has established a military base in the Coco islands, leased from neighboring Myanmar; is helping build the Gwadar Pasni port in Pakistan; has established good relations with several African states and has some leverage with Iran, the official added.



China's feverish military modernization is the most destabilizing factor for Indian national security, the official said.



The annual Indian Defence Ministry report of 2009-10 describes what it views as China's growing threat to the region: "China's stated objectives, in their White Paper of National Defence in 2008, of developing strategic missile and space-based assets and of rapidly enhancing its blue-water navy to conduct operations in distant waters, as well as the systematic upgrading of infrastructure, reconnaissance and surveillance, quick response and operational capabilities in the border areas, will have an effect on the overall military environment in the neighborhood of India."



PREPARING FOR CHINA

India has begun improving its infrastructure and road system along its border with China, a senior Indian Army official said. Special troops are being trained to deploy along the Chinese border, and tenders have been floated to buy ultralight 155mm guns along with a variety of helicopters and light combat tanks.



The Air Force has procured C-130J aircraft from the United States to speed deployment of troops, and efforts are being made to improve surveillance and search assets, including through UAVs.



India and China fought a brief battle in 1962 over a border territory issue. The border between India and China is currently defined by a 4,056-kilometer Line of Actual Control (LAC), which is neither marked on the ground nor on mutually acceptable maps. Efforts since the mid-1980s to have a recognized LAC have made little headway.



The dispute involves the longest contested boundary in the world; both nations claim the same 92,000 square kilometers of territory.



India and Japan have also upgraded their defense relations and in December 2009 established a long-term framework to review defense ties on a regular basis. Maritime security dialogue between the two nations has been taking place for some time.



Indo-Japanese strategic ties are part of an effort to counter China's growing influence in the area, said Mahindra Singh, retired Indian Army major general and defense analyst. The dependence of Japan and India on oil imports from the Arabian Gulf is another major driver behind their growing relationship, Singh said.



India and Bangladesh also signed three security-related deals during the Jan. 11-14 visit of Bangladesh Prime Minister Sheikh Hasina to New Delhi. The pacts relate to treaties on mutual legal assistance in criminal matters, mutual transfer of convicted prisoners, and cooperation in the fight against international terrorism, organized crime and illegal drug trafficking.



India is concerned that Bangladesh may drift toward China. There have been reports that China has access to Bangladesh ports and may try to locate a military base there, Singh added.



PROCUREMENT DELAYS

The United Progressive Alliance government, which came to power for the second term in May 2009, hiked the defense budget by 34 percent to $28.9 billion for the current financial year, which ends March 31, but a cumbersome Defence Ministry bureaucracy still slows procurement. The result is that not a single 155mm artillery gun has been procured since 1986 because of a cautious political process that has led to several foreign bidders being blacklisted on corruption charges.



The Indian Army desperately needs 155mm/52-caliber guns, a senior Army official said.



India is preparing for possible conflict with China and Pakistan, but New Delhi cannot afford to overreact on a border issue with China, Singh said.



"Both China and India cannot afford to have a war in the near future, as their economic growth path would be severely derailed," Mathews said
  Reply
#59
[quote name='ankit-s' date='03 March 2010 - 04:12 AM' timestamp='1267569259' post='104734']

[size="3"]Shifting Geopolitics Realigns Indian Relations[/size]



NEW DELHI - India has shifted back into a closer relationship with Russia as New Delhi perceives a growing threat from China while the U.S. Obama administration has focused on engaging traditional foe Pakistan to aid its Afghanistan campaign, defense analysts said.



While New Delhi signed a $2.1 billion contract with the United States to purchase six P-8I long-range maritime reconnaissance aircraft in January 2009, India and Russia closed the year by signing an agreement on nuclear cooperation and resolving the long-standing Admiral Gorshkov aircraft carrier dispute. India agreed to pay $1.2 billion above 2004's contracted price of $800 million for the ship.



The countries also [color="#0000ff"]finalized the joint production of a fifth-generation combat jet for $10 billion,[/color] and the Indian Navy has decided to buy [color="#0000ff"]additional MiG-29K aircraft from Russia worth about $1.2 billion[/color].



India and Russia signed a nuclear cooperation agreement in December 2009 that offers India better terms than the Indo-U.S. nuclear cooperation agreement, which has yet to become operational, Indian officials said.



[/quote]

Thanks Ankit for posting this.



One of the crucial payback for playing strategic cooperation with Indian post 1998 Pokhran, Op-Prakaram and Nuclear Deal is to reward French and Russia. The carrot of the MRCA deal worth $12 Billion had been hanging up the pole for long, and it was critical for India for split the deal between two supplier countries (on Indian TOT terms) between Russia and France/Europe.



US had a chance in between, but the crooked tail of the dog has shown to not become straight and remain crooked under Obama; thus the US Teens (F-Fifiteen or F-Eighteens ) will remain naked, and no new bones thrown at them (P8I and C130 is enough bone for the dog)



Now with the $10 Billion (for FGFA) and change (for Mig29-K, Akula and Greshkov) going to Ivan, the MRCA can now settle for the best technical fit for IAF, and I hope Rafael or Gripen will be chosen for the full compliment of 128 aircrafts, instead of splitting it between two supplier that will be a costly maintainace and up-time nightmare for IAF and India.
  Reply
#60
ankit-s

Because of copyright issues, please provide links to article site (URL of article).

Thanks.
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