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    PAK FA, T-50: News

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    GarryB
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    Re: PAK FA, T-50: News

    Post  GarryB on Fri Sep 17, 2010 4:12 am

    But this can also be said about T-50; rather this effect will be much more pronounced

    Not really because the T-50 has IRST and the F-22 does not so the T-50 could fly around in AB all day and that wouldn't effect the F-22s ability to see it.

    http://4.bp.blogspot.com/_7SvKgIpSQ6k/S5hC0bvEPpI/AAAAAAAAAgo/TgwjhYIVG4s/s640/PAK-FA_F22_Topviews_Radars.jpg

    This is wrong... the T-50 has 3 radar antenna in its nose, one large X band radar pointing forward and two small X band antenna facing sideways like a SLAR on a recon plane.
    The radar on the wing leading edge will likely take up the entire leading edge... that is why no one fits them to the nose position of fighters because they have to be long to work because of the frequency they operate at.

    @Nightcrawler
    What all that stuff you posted basically boils down to is the assumption that the F-22s radar return on high frequency X band radar, which is the radar frequency traditionally used for detection, tracking and terminal homing (because of its precision) that to track an F-22 requires the radar to track everything insect size and larger, which is too much. To categorise the insects and other things floating around like Clouds as noise is to also categorise the F-22 as noise so it becomes invisible.
    There was a similar problem a few decades ago with the An-2 biplane that the Soviets used as a light transport and also for dropping small teams of paratroopers.

    When flying low and slow a modern radar looking down would detect the plane but the plane would be hidden in the enormous radar reflection of the ground. To remove the ground as a reflector they simply used the doppler effect so anything that was not moving at 120km/h was removed from the radar display so that cars did not appear as targets. This meant that the An-2 flying at 90km/h also disappeared and so it was the first stealth aircraft!

    The difference in this case is that instead of looking down into a huge reflection of the ground looking for an insect sized target you are looking up and let me tell you there are no insects above 10,000m let alone the 20,000m operating ceiling of the F-22. Another thing is that few insects fly at anywhere near the speed of the F-22 so actual insects and clouds and other things that might be mistaken for F-22s can be removed as noise if they are moving at less than 50km/h which should remove everything except for those super cruising F-22s.

    Another issue is of course that the shape of an aircraft only matters to radar that can actually detect shape like X band radar. L and N band radar resonates of the aircraft as a single pulse and detection range is not effected by shaping at all so a wing mounted L band radar that can detect an Su-27 at 400km can detect a T-50 or an F-22 at 400km too.
    That is why they haven't wasted billions making the T-50 super stealthy... there will be no point in 20 years.

    Regarding the shooting down of the F-117 lets put it in perspective.
    It was NATO vs Serbia. NATO that looks on paper to be the most powerful military force the world has ever seen vs Serbia.
    The F-117 was claimed to be completely invisible, undetectable.
    It was going to go into the Soviet Union in the 1980s completely undetected but an enormous range of radars large and small and evade S-300 and S-300V SAM sites and Mig-31 interceptors and Su-27 fighters (note both with IRST sensors) and drop laser guided bombs on very high priority targets and then fly home in safety despite thousands of enemy fighters patrolling the skies etc etc etc.

    If the shoot down was luck then why didn't the Iraqis get some too?

    If you can base an air defence around luck why waste money on guided SAMs when unguided Grad rockets are much cheaper... just fit them with airpresure fuses so they explode at certain heights and fire barrages everytime you hear an aircraft engine?
    Try this.
    Get a digital camera and go out into the middle of nowhere that is under the flight path of an airport but far enough away from any airport so that all the aircraft are at 10,000m or so (ie 30,000ft would be a normal operating height for an airliner) so you can't hear its engines.
    Close your eyes and get your map out and look up the flight schedule and work out, based on airspeed and time when the next aircraft flys over.
    Using that fly over time you can take 30 shots of the sky but only planes caught in the dead centre of the picture count.
    You have to take the photos with your eyes closed and you are not allowed to look for aircraft before or even after you take the photos.
    Now do it again... at night.
    Luck my a$$.
    They wouldn't have been able to mass large numbers of SAMs to fire at the F-117 simply because a large group of SAMs would be detected and destroyed.
    They probably only had one or maybe two launchers so that means about 6 shots maximum at the target... and if you can't see the target your chances of hitting it with even 6 shots is so close to zero it is not worth the effort.
    The reality is that the F-117 was not invisible, what they probably did was illuminate the target with the radar of another battery from behind where the F-117 was coming from and so the radar emissions scattered from the target away from the emitting antenna would be reflected towards other batteries based in other places.
    This means several things... first it means they knew what the target was going to be... not rocket science... they were there to defend something so they knew what the target of any plane in that area was.
    Second it means they knew the direction it was coming from, which again is a no brainer because I am sure they would have taken steps to determine where NATO deployed its aircraft to and which were where.
    Third it means that there was a spy at the NATO base who watched the F-117s take off to pass that information on to the Serbian air defences... not really a surprise.
    Fourth... and most importantly they would need to aim the guidance beam at the F-117 and keep it on it for the missiles to guide. These SA-3s are not vanilla old models they have had upgrades and those upgrades probably included optical backup guidance which was probably used by the first unit to mark the aircraft with a pencil radar beam.
    I rather doubt luck is why the F-117 was brought down, that would take a lot of organisation and coordination.

    The reason the Serbs didn't seem to do very well with only two confirmed kills is simply because NATO was so scared it operated above the effective altitude of most Serbian systems. Another factor often ignored in the west is that the west used a lot of unmanned platforms and they lost something like 50 of those during the campaign.
    If the Serbian Air Defence Force failed because it only brought down 2 manned aircraft then the all powerful NATO force failed because after 74 odd days of total air superiority and air domination it completely failed in its mission to defeat the Serbian armed forces, and the Serbian air defence forces were as dangerous to NATO aircraft on day 74 as they were on day 1.

    Sounds like a fail fail fail for NATO to me.

    In the end NATO had to resort to lying to Russia to make it think it would have a role in the peacekeeping afterwards to get the Serbs to sign and when the Russians found they had been double crossed they raced forces to Pristina.
    The US General in charge reacted by ordering the local British forces to take Pristina, by force if necessary... to which the British General Michael Jackson (no joke... look it up) told him to get stuffed, that he would have to work with the Russians and he wasn't going to start WWIII over this.
    Sensible chap IMHO. (The brit, not the yank).

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    Re: PAK FA, T-50: News

    Post  nightcrawler on Fri Sep 17, 2010 9:15 pm

    When flying low and slow a modern radar looking down would detect the plane but the plane would be hidden in the enormous radar reflection of the ground. To remove the ground as a reflector they simply used the doppler effect so anything that was not moving at 120km/h was removed from the radar display so that cars did not appear as targets. This meant that the An-2 flying at 90km/h also disappeared and so it was the first stealth aircraft!

    Thnxxx

    Sensible chap IMHO. (The brit, not the yank).

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    Re: PAK FA, T-50: News

    Post  nightcrawler on Sat Sep 18, 2010 11:54 am

    Post n°72 @GarryB

    What is called stealth in modern fighter and bomber aircraft is actually an attempt to delay not just detection but the ability to lock on an engage by an enemy air defence system or interceptor aircraft.
    Too vague. What is called 'stealth' is properly known as 'low radar observability' or 'low radar reflectivity'. Since radar is the most productive sensor we have today, any body that is 'low radar reflective' will REDUCE the distance in which said body become a statistical certainty.
    by the way The US never claimed that our 'stealth' aircrafts are 'invisible' to radar. The word 'stealth' or 'invisible' are casual, not technical, terms, for media and public consumption.
    The stealthy plane uses its physical shape and surface coatings to reduce the high frequency radar waves of the enemies sensors and weapons to reduce the range at which you can be both detected and engaged.
    The point is that only high frequency radar waves are that are short enough to even detect shape will be effected by the shape of the aircraft.
    This is OK because traditionally short wave radar is used for terminal guidance (ie for AMRAAM and SPARROW etc etc) either from the missile itself (AMRAAM) or from the launch platform (SPARROW), and the same for ground launched radar guided missiles like HAWK and PATRIOT.
    High frequency radar gives the precise position of the target whereas longer range radar will create a larger return somewhere inside which is the target... good enough for detection but simply not accurate enough (in the past) for terminal guidance.
    The phrase 'high frequency' is meaningless. The correct descriptors are: decimetric (m), centimetric (cm), and millimetric (mm). They are wavelength descriptors. A wavelength can be measured from several points...From crest to crest, or trough to trough, or from zero to zero crossings. For example...
    http://www.dxing.com/frequenc.htm
    The distance between the peaks of two consecutive cycles is measured in meters.

    ...a frequency of 9680 kHz would be equivalent to a wavelength of 30.99 meters, which we would round to 31 meters. Thus, 9680 kHz, 9.68 MHz, and 31 meters all refer to the same operating frequency!
    Long wavelengths or low freqs produces long pulses and when it comes to target information, such as speed, altitude, heading, and aspect angle, short pulses or high freqs are desirable. Radar detection works on the principle of 'finite pulse length' to calculate those important target information. The radar computer calculate the timing intervals between the trailing edge of one pulse to the leading edge of the next pulse, of what it transmit, against what it receive when those pulses impact a body and reflect. The shorter the pulses, outgoing to the body or echoes off the body, the smaller the time intervals between them, similar to slow motion videography where the higher the shutter speed, the more detailed the 'slo-mo' video.

    A series of pulses is called a 'pulse train'. The pulse characteristic that is called 'finite pulse length' mean there is a leading and trailing edge to a pulse, but it also mean there is a finite amount of energy in each pulse. Finite energy equal to shorter distance traveled before the pulse is completely dead via 'atmospheric attenuation' or absorption by the many microscopic obstacles in the way, such as water molecules or simple dust particles. Therefore there is a trade off, shorter pulses produces higher target resolutions but at the expense of distance, whereas longer pulses travels further but at the expense of target resolutions.

    Another important relationship is between wavelength, beamwidth, and antenna dimensions. Basically, the larger the array, and antenna is NOT necessarily the array, the tighter the beamwidth, and the greater the distance. The US Navy's Aegis radars are centimetric (ghz), those radars can reach out to hundreds of km., but each array is meters in diameter. For any wavelength, the smaller the array, the wider the beam. Missile's radars are also centimetric (ghz) but because of their small diameter arrays inside the small radomes, which give the antennas limited scan movements, missiles usually require some degrees of external guidance. That mean for a missile to be effective despite its small radar array, the missile MUST use the centimetric (ghz) bands, short pulses, and high pulse repetition freq (PRF).

    US 'stealth' aircrafts are shaped against centimetric freqs, the bands that will produce the highest target resolutions. The millimetric freqs are too vulnerable to atmospheric losses to be of use outside of specialized applications.

    What I am trying to say is that the US has the stealth, but it still uses its old weapons that its own stealth was designed to work against like AMRAAM.
    This make no sense. The F-22's radar reflectivity has nothing to do with other aircrafts'. If others has higher radar reflectivity, the AMRAAM works upon that.
    The Russians have fitted long wave AESA antenna arrays within the leading edges of the wings of both the T-50 and the Su-35 which will not be effected by the thin coatings of RAM or the shaping of the aircraft like F-35 and F-22 and B-2.
    Regarding that important relationship between array dimensions, freq employed that affect beamwidth, the claim that the T-50's wing leading edge radars are effective against the F-22 is dubious at best precisely because of their small arrays.
    The US method of finding stealth targets is with high power broadcasts of AESA radars... hardly the best method!
    This make no sense. No one else has the F-22 equivalent
    The Russians have a range of BVR IR guided missiles and will no doubt expand that to include IIR guided weapons too.
    Infrared is passive sensor, meaning it relies on target characteristics to deduce target information. Currently, infrared can only give target direction, not radar-like resolutions such as speed, altitude, heading, and aspect angle. At best, complex IR arrays can produce target speed, hardly effective against a maneuvering fighter aircraft.
    Add to that the US plans to have their F-22s flying high and at supersonic speeds the IR signals from supersonic leading edges will make them targets rather than hunters.
    If leading edge IR emissions are so effective as claimed, then all missiles should have been IR equipped a long time ago. Fact is that such IR emissions are not consistent and insufficiently concentrated in a spatial environment.

    For example...
    http://adsabs.harvard.edu/abs/1993thph.confQ....B
    The present analysis of wing leading-edge radiance assumes that the optical axis of the sensor aligns with the chord line of the wing, and that the leading edge falls within the instantaneous field-of-view of the sensor. Wing radiance rapidly decreases with increasing angular dependence of surface emissivity. A sharp leading edge and a wedgelike shape minimize grey-body radiation from a wing. IR radiation is shown to strongly depend on the angular dependence of emissivity.
    For the highlighted, it mean the IR sensor's position is best head-on, else IR radiance decreases as angular difference between sensor and wing increases.

    Lastly GarryB plz elaborate why you think there is any resemblance b/w MiG-25 & F-15/YF-23 I dont see any....Belenko's defection with one MIG-25 debunked this.

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    Re: PAK FA, T-50: News

    Post  GarryB on Sun Sep 19, 2010 5:49 am

    by the way The US never claimed that our 'stealth' aircrafts are 'invisible' to radar. The word 'stealth' or 'invisible' are casual, not technical, terms, for media and public consumption.

    Internal documents about the projected usage of F-117s and F-22s and B-2s talk about penetrating air defences with no chance of detection.

    The phrase 'high frequency' is meaningless.

    The link you gave:

    http://www.dxing.com/frequenc.htm

    A quote from the link you gave:

    For example, the 17-meter ham radio band is actually higher in frequency than the 16-meter broadcasting band.

    For high frequency to be meaningless there cannot be an order of frequency from low to high. If a frequency as a position above or below another frequency then there is such a thing as high and low frequency.

    Long wavelengths or low freqs produces long pulses and when it comes to target information, such as speed, altitude, heading, and aspect angle, short pulses or high freqs are desirable.

    So now high and low frequencies are not meaningless? Smile

    Therefore there is a trade off, shorter pulses produces higher target resolutions but at the expense of distance, whereas longer pulses travels further but at the expense of target resolutions.

    I know, though certain layers of the Earths atmosphere can be used to bounce waves of certain frequencies to extend the useful range beyond the visual horizon.

    The millimetric freqs are too vulnerable to atmospheric losses to be of use outside of specialized applications.

    They are developing into very useful bands for terminal missile guidance close to the ground where weather effects are at their worst. From MMW Hellfire to KASHTAN and of course the as yet unseen Russian ATGMs mounted on their Mi-28N and Ka-52s both of which use MMW and CM Wave radar.

    There was talk that the Kh-15 Kickback used MMW radar guidance in a proposed anti ship model and that there was an equivelent Kh-58 (AS-11) anti ship model.

    This make no sense. The F-22's radar reflectivity has nothing to do with other aircrafts'. If others has higher radar reflectivity, the AMRAAM works upon that.

    What I mean is that they don't have any BVR IR guided weapons like the R-27ET so in effect they have developed an aircraft optimised to defeat their own weapons systems.

    Regarding that important relationship between array dimensions, freq employed that affect beamwidth, the claim that the T-50's wing leading edge radars are effective against the F-22 is dubious at best precisely because of their small arrays.

    The full length of a T-50 or Su-35 wing is a small array? The drawing you posted certainly shows a very small array but can we assume it is accurate... especially when it does not show all three nose arrays?

    What other purpose would they use L and N band arrays on an interceptor? Do you think they don't know what they are doing?

    [qutoe]This make no sense. No one else has the F-22 equivalent[/quote]

    How arrogant are the Americans to think there will never be another 5th generation fighter made in the service life of the F-22?

    Infrared is passive sensor, meaning it relies on target characteristics to deduce target information. Currently, infrared can only give target direction, not radar-like resolutions such as speed, altitude, heading, and aspect angle. At best, complex IR arrays can produce target speed, hardly effective against a maneuvering fighter aircraft.

    Sonar is a passive sensor yet Submarines seem adept at finding the distance to things without even seeing them.
    IRSTs give very precise angular information that can be used to steer a radar of any frequency directly at a target. A single very short pulse will give range data. With R-27ET missiles having a rather long range it would probably be safe to assume such a weapon could outrange the detection capability of the IRST to detect an F-22.

    If leading edge IR emissions are so effective as claimed, then all missiles should have been IR equipped a long time ago. Fact is that such IR emissions are not consistent and insufficiently concentrated in a spatial environment.

    If stealth aircraft are so effective as claimed, then all aircraft should have been stealthy a long time ago. Fact is that such stealth designs are not consistent and insufficiently concentrated in a spatial environment.
    ...and they are ridiculously expensive too.

    I am not making fun of you, I am testing your logic. If your logic is sound then it shouldn't matter what I put in the sentence as the subject, if it is logical it should make sense.

    Stealth is a measure in the measure and countermeasure battle. This battle is never ending and no measure stays effective forever. There is a reason a country as rich as the US can't even afford more than 20 B-2s or 200 F-22s and why many of the US's allies are finding the F-35 too expensive too.
    For most of the conflicts the US is likely to fight it simply could have used non stealthy aircraft and the results would be the same. The one exception would be a conflict against the Soviet Union... and shock! horror! that conflict is not going to be determined by any sort of fighter aircraft.

    There is a thread on this forum about the Soviet Union making too many tanks during the cold war... well in 50 years time there might be a thread about how the US wasted all that money on stealth fighters that didn't matter against the Russians or the Taleban. They looked good at airshows and won a lot of exercises, but they weren't much use for anything else.

    For the highlighted, it mean the IR sensor's position is best head-on, else IR radiance decreases as angular difference between sensor and wing increases.

    The F-22 is supposed to roar around at supersonic speeds at 20,000m and zap targets below it using its high speed to be a hard target for climbing missiles, while giving a mach 1.5 or so boost to the AMRAAMs it fires. Now if it is going to do this it will leave the combat area fairly quickly unless it orbits. If it is going to orbit then anything on the ground or in the air will get plenty of chances to see it head on to detect its presence.

    Lastly GarryB plz elaborate why you think there is any resemblance b/w MiG-25 & F-15/YF-23 I dont see any....Belenko's defection with one MIG-25 debunked this.

    The Mig-25 was totally developed and flying before the requirements for the F-15 were even formulated. The F-15 was designed to try to beat what the Mig-25 was anticipated to be, so it adopted the Mig-25s layout... ie similar wing shape, two vertical seperated tail surfaces and two horizontal tail surfaces and two engines side by side in the rear tail area.
    The F-22 has the same basic layout.
    The T-50 also has the same layout but then you could say it is based on the Su-27 which also has the Mig-25 layout too.

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    Re: PAK FA, T-50: News

    Post  Austin on Sun Sep 19, 2010 8:21 am

    I dont think the concept of stealth was ever claimed to be completely invisible either by Americans or Russians.

    The term the Americans use is LO or VLO ( Low Observability/Very Low Observability ) , its a combination of VLO,Radar Coverage Gaps carefully studied ,Reduced Ability of Radar to detect inherently VLO Aircraft ,ELINT/Jamming and Tactics that makes the Stealth seems so invisible.

    Even the Russian recently said that the PAK-DA cannot be made complete invisible.

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    Re: PAK FA, T-50: News

    Post  nightcrawler on Sun Sep 19, 2010 4:23 pm

    If stealth aircraft are so effective as claimed, then all aircraft should have been stealthy a long time ago. Fact is that such stealth designs are not consistent and insufficiently concentrated in a spatial environment.
    ...and they are ridiculously expensive too.

    I am not making fun of you, I am testing your logic. If your logic is sound then it shouldn't matter what I put in the sentence as the subject, if it is logical it should make sense.

    you sir very clever Twisted Evil Twisted Evil

    The Mig-25 was totally developed and flying before the requirements for the F-15 were even formulated. The F-15 was designed to try to beat what the Mig-25 was anticipated to be, so it adopted the Mig-25s layout... ie similar wing shape, two vertical seperated tail surfaces and two horizontal tail surfaces and two engines side by side in the rear tail area.

    Do correct me if I am wrong but isn't F-15 was flying high before US even had a look on defected MiG-25

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    Re: PAK FA, T-50: News

    Post  GarryB on Mon Sep 20, 2010 4:06 am

    Do correct me if I am wrong but isn't F-15 was flying high before US even had a look on defected MiG-25

    Yes. They didn't copy a plane, they copied the idea of a plane.

    They thought the Mig-25 was an air superiority super fighter with an enormous radar and super powerful engines able to fly at mach 3 that will clean all US aircraft from the skies.
    When they got a look at one they found it had very sophisticated bits (when you land this plane from the 1950s you apply full braking because it has an anti skid braking system built in for example.) but it also have very basic bits. The radar for example had comparable power to the ground radars covering the north pole looking for Soviet bombers and missiles, but instead of having modern transistors it had older tubes for its electronics. The simple reason was that when it was designed transisters didn't exist and it hadn't been upgraded because it was an interceptor and high speed recon and it was already very good at its job.
    By the time the US found out their mistake it was too late, the resulting F-15 had already been designed to fight an enemy that didn't exist.

    you sir very clever

    I wish... merely a standard logic test. If an argument makes sense then it should make sense no matter what the subject.

    I dont think the concept of stealth was ever claimed to be completely invisible either by Americans or Russians.

    Really? I seem to recall statements from the Americans about this or that airspace over a certain city they happened to be bombing at the time was the most heavily defended airspace in the world and that their stealth aircraft could operate without support with impunity and without being seen.
    Of course they would also say that x number of weapons were fired blindly into the air but nothing came close.

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    Re: PAK FA, T-50: News

    Post  havok on Mon Sep 20, 2010 8:31 am

    GarryB wrote:The Mig-25 was totally developed and flying before the requirements for the F-15 were even formulated. The F-15 was designed to try to beat what the Mig-25 was anticipated to be, so it adopted the Mig-25s layout... ie similar wing shape, two vertical seperated tail surfaces and two horizontal tail surfaces and two engines side by side in the rear tail area.
    So what? How does this proved the F-15's design to be based upon the MIG-25? It does not.

    GarryB wrote:Yes. They didn't copy a plane, they copied the idea of a plane.

    They thought the Mig-25 was an air superiority super fighter with an enormous radar and super powerful engines able to fly at mach 3 that will clean all US aircraft from the skies.
    When they got a look at one they found it had very sophisticated bits (when you land this plane from the 1950s you apply full braking because it has an anti skid braking system built in for example.) but it also have very basic bits. The radar for example had comparable power to the ground radars covering the north pole looking for Soviet bombers and missiles, but instead of having modern transistors it had older tubes for its electronics. The simple reason was that when it was designed transisters didn't exist and it hadn't been upgraded because it was an interceptor and high speed recon and it was already very good at its job.
    By the time the US found out their mistake it was too late, the resulting F-15 had already been designed to fight an enemy that didn't exist.
    Incorrect.

    http://www.aviation-history.com/airmen/boyd.htm
    Boyd then used E-M as a design tool. Until E-M came along, fighter aircraft had been designed to fly fast in a straight line or fly high to reach enemy bombers. The F-X, which became the F-15, was the first Air Force fighter ever designed with maneuvering specifications. Boyd was the father of the F-15, the F-16, and the F-18.
    Boyd's Energy-Management Theory for air combat predated the MIG-25 and it heavily influenced the development of the F-15 and F-16. The F-111's first flight was in 1964 and eventually it failed to impress the US Navy, who took its TF-30 engines and built those engines into the F-14, which had its first flight in 1970.

    http://en.wikipedia.org/wiki/VFAX
    VFAX was essentially the Navy counterpart to the Air Force's FX study which eventually led to the F-15 Eagle air superiority fighter.

    When accepted by the Navy after a competition, the VFAX and VFX would become the F-14 Tomcat, the first dedicated US Navy air superiority design since the F-8 Crusader.
    The history goes this way: The F-X project was supposed to be an improved derivative of the F-111, which the US Navy rejected. The USN then created the VFAX/VFX program as a counter to the USAF's F-X project. The VFAX then became the F-14. The US Congress then threatened the USAF with the F-14, just like how the F-111 was supposed to be a Navy fighter as well. The USAF by this time was flying the F-4, which was originally a Navy fighter that was forced upon the USAF. The USAF was determined to have its own air superiority fighter that was independently developed from any Navy project, hence the F-X being the F-111 derivative. The original F-X was supposed to have swing wings like the F-111 and the F-14.

    http://www.ausairpower.net/Profile-F-15A-D.html
    The idea of an air-air fighter was under consideration as early as 1965, but the subsequent FX study generated by USAF Systems Command created the concept of a 60,000 lb swing wing machine much like the F-111, already under criticism for its inability to do what it wasn't built for.

    Boyd rapidly sunk the idea of a swing wing, on grounds of extra weight and complexity. He then proceeded to optimise the engine (turbofan being then the in thing) bypass ratio concluding that a turbojet is best, but accepting 1.5 as a reasonable compromise (later reduced).
    The F-15's first flight was in 1972 but its program inception as the F-X was six years prior. When Boyd began his Pentagon assignment as a major in 1966, there were no hardware development for the F-X. Boyd took the F-X apart and imposed his EM theory upon the design. Boyd's fighter was the F-16, never the F-15 even though he was called the 'Father' of it. The F-16 was the result of Boyd's frustrations with the politics, civilian and military, of F-X/F-15 project. The belief is that if Boyd had his way, what we know today as the F-16 would have been designated F-15. Boyd was openly contemptuous of the F-14 back then. Today, F-14 pilots do not like to mix with the F-16.

    Boyd's EM theory won over and the F-15's large wing area came from the F-86's philosophy, which was a high altitude interceptor and that mission require large wing area. This does not mean the F-15 came from the F-86. What it mean is that given a mission that demanded a set of performance criteria, a design is then bounded by the laws of physics to have a certain wing shape and surface area, or two engines instead of one, or intakes in certain positions, and so on...Other EM principles eventually shaped the F-X into current F-15. Given the fact that one of the F-15's missions is to be a high altitude and Mach capable interceptor, and the MIG-25 was supposed to be that high altitude and Mach capable interceptor, any visual similarities between the F-15 and the older MIG-25, are coincidental, not intentional, and quite superficial. What made the F-15 a superior aircraft over the MIG-25 was of Boyd's EM theory and US technology lead. Many would like to believe that the US copied the MIG-25 into the F-15 but the facts says otherwise.


    Last edited by havok on Mon Sep 20, 2010 9:03 am; edited 1 time in total

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    Re: PAK FA, T-50: News

    Post  havok on Mon Sep 20, 2010 8:49 am

    GarryB wrote:Internal documents about the projected usage of F-117s and F-22s and B-2s talk about penetrating air defences with no chance of detection.
    Based upon known radar practices. That still does not negate the fact that the US never claimed anything to be 'invisible' to radar detection.

    GarryB wrote:For high frequency to be meaningless there cannot be an order of frequency from low to high. If a frequency as a position above or below another frequency then there is such a thing as high and low frequency.
    Technically speaking, there are no such things as 'high' or 'low', but there are such things as 'higher' or 'lower'. Your argument centered around the phrasing 'high frequency' which give the readers no valid references, whereas the words 'decimetric', 'centimetric', and 'millimetric' are far more accurate descriptors.

    GarryB wrote:So now high and low frequencies are not meaningless?
    Never said so. What was pointed out was the phrasing 'high frequency'. It give the readers no references on the spectrum scale.

    GarryB wrote:They are developing into very useful bands for terminal missile guidance close to the ground where weather effects are at their worst. From MMW Hellfire to KASHTAN and of course the as yet unseen Russian ATGMs mounted on their Mi-28N and Ka-52s both of which use MMW and CM Wave radar.

    There was talk that the Kh-15 Kickback used MMW radar guidance in a proposed anti ship model and that there was an equivelent Kh-58 (AS-11) anti ship model.
    Yes...Terminal targeting schemes are specialized applications. Millimetric bands are nowhere as efficient as centimetric bands for general purposes and even less so than decimetric bands.

    GarryB wrote:What I mean is that they don't have any BVR IR guided weapons like the R-27ET so in effect they have developed an aircraft optimised to defeat their own weapons systems.
    And you are wrong. This argument wrongly assume that it is less expensive to produce a radar low observable aircraft than a BVR missile.

    GarryB wrote:The full length of a T-50 or Su-35 wing is a small array? The drawing you posted certainly shows a very small array but can we assume it is accurate... especially when it does not show all three nose arrays?
    Why is a radar antenna shaped more or less like a circle or derivatives of it? Array shape determine beam shape which in turn affect the scan pattern...Go here...

    http://www.ausairpower.net/APA-2009-06.html
    Figure 1: The array geometry produces a fan shaped mainlobe which is swept in azimuth by phase control of the twelve TR modules, providing a 2D volume search capability.
    Figure 1 has a reasonably accurate example of what this wing leading edge radar beam shape would look like -- a fan. This beam shape is best for 2D scan pattern. Azimuth is a side-side scan motion. Elevation is an up-down scan motion. A fan shape beam, azimuth or elevation, is not good for track or targeting schemes. The best targeting beam is the casually called the 'pencil' beam and is usually use with boresight mode where the beam moves in a circular motion, keeping the target always slightly off-centered inside this circle. So yes, the wing leading edge arrays are indeed smaller than what is normally employed.

    GarryB wrote:What other purpose would they use L and N band arrays on an interceptor? Do you think they don't know what they are doing?
    Of course they know what they are doing. But that does not mean they can defy the laws of physics. The wing leading edge radars have limited usage and therefore limited efficacy.

    GarryB wrote:How arrogant are the Americans to think there will never be another 5th generation fighter made in the service life of the F-22?
    Never said so. What was said was that the US is currently not facing any F-117 equivalent, let alone an F-22 peer. And the F-117 is retired.

    GarryB wrote:Sonar is a passive sensor yet Submarines seem adept at finding the distance to things without even seeing them.
    Wrong. Sonar is not a passive sensor. Just like radar, it is an active sensor. You know about the classic 'Ping', right? Watch 'The Hunt For Red October' again.

    GarryB wrote:IRSTs give very precise angular information that can be used to steer a radar of any frequency directly at a target. A single very short pulse will give range data. With R-27ET missiles having a rather long range it would probably be safe to assume such a weapon could outrange the detection capability of the IRST to detect an F-22.
    Infrared sensor is 'angular' only in the sense that the system give the pilot an angle displacement from the current position, similar to 'north by northeast' direction. On the other hand, radar can tell if an approaching aircraft is pointing at an angle away from the aircraft. The analogy is that you can tell if someone is facing you as well as he is standing on your left side. With infrared sensor, you can only tell if he is standing on your left side but not if he is facing you. Infrared emission still has to obey the laws of physics where energy decreases with distance: inverse-square law.

    http://en.wikipedia.org/wiki/Inverse-square_law
    In physics, an inverse-square law is any physical law stating that some physical quantity or strength is inversely proportional to the square of the distance from the source of that physical quantity.
    Wing leading edges can have their IR emissions controlled by internal cooling or with materials. But because of the inverse-square law and the fact that we are talking about an edge, this IR emission will be atmospherically attenuated. This is why IR sensor equipped missiles should still be looking at a strong heat source, like the jet exhaust, instead of a head-on view. It is not impossible but just very difficult for an IR missile to use wing leading edge sources. If anything, sunlight glinting off the canopy is a much better IR source.

    GarryB wrote:If stealth aircraft are so effective as claimed, then all aircraft should have been stealthy a long time ago.
    Say what? The Iraqi air defense thought low radar observable capability effective enough.

    GarryB wrote: Fact is that such stealth designs are not consistent and insufficiently concentrated in a spatial environment.
    ...and they are ridiculously expensive too.
    Completely nonsensical statement.

    GarryB wrote:I am not making fun of you, I am testing your logic. If your logic is sound then it shouldn't matter what I put in the sentence as the subject, if it is logical it should make sense.
    Considering how you do not know basic radar detection principles, you flunk your own test.

    GarryB wrote:Stealth is a measure in the measure and countermeasure battle. This battle is never ending and no measure stays effective forever.
    It just need to stay effective long enough. But as long as no one can produce a countermeasure then we remain in the advantage.

    GarryB wrote:There is a reason a country as rich as the US can't even afford more than 20 B-2s or 200 F-22s and why many of the US's allies are finding the F-35 too expensive too.
    That mean producing a low radar observable aircraft is not as easy as you think. What you apparently forgot is that no one has a monopoly on radar detection knowledge. Technology allows the refinement of that knowledge and in that, the US has the advantage. That mean we know better than most on how radar signals behave on a body and how to affect, perhaps even control, those behaviors. If we can affect behaviors, we can reduce the efficacy of any seeking radar. Like it or not, 'stealth' works and works very well.

    GarryB wrote:For most of the conflicts the US is likely to fight it simply could have used non stealthy aircraft and the results would be the same.
    Possibly...But in war, vital to winning and perhaps equally important to winning, is to inflict maximum losses to the enemy while minimizing one's own. Having a fleet of radar low observable aircrafts helps US in both.

    GarryB wrote:There is a thread on this forum about the Soviet Union making too many tanks during the cold war... well in 50 years time there might be a thread about how the US wasted all that money on stealth fighters that didn't matter against the Russians or the Taleban. They looked good at airshows and won a lot of exercises, but they weren't much use for anything else.
    Wasted? Deterrence is better than war. You might as well call all weapons as 'wasted' expenditures since not all were employed in the wars fought. This is a weak argument against US 'stealth' aircrafts.

    GarryB wrote:The F-22 is supposed to roar around at supersonic speeds at 20,000m and zap targets below it using its high speed to be a hard target for climbing missiles, while giving a mach 1.5 or so boost to the AMRAAMs it fires. Now if it is going to do this it will leave the combat area fairly quickly unless it orbits. If it is going to orbit then anything on the ground or in the air will get plenty of chances to see it head on to detect its presence.
    Wrong. Radar detection is essentially a statistical process. Even if you can visually acquire an F-22 with your own eyes, that does not mean your radar can. Radar detection is statistical in the sense that if ten pulses impact an aircraft and only two echoes are produced, the system will reject these two echoes as anomalous. You can force, or reprogram, the system to accept two out of ten but that would mean you will spend so much time and expend so much effort in chasing after false positives, aka 'ghosts', that eventually you will go bankrupt or too exhausted to respond when a true positive attack your position. Raise the threshold to five out of ten and there will be less work. There are plenty more details about this process but for now, it is sufficent to say that the B-2, F-22, and F-35 are designed to deny the enemy that consistent statistical analysis.

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    Re: PAK FA, T-50: News

    Post  havok on Mon Sep 20, 2010 9:02 am

    GarryB wrote:What all that stuff you posted basically boils down to is the assumption that the F-22s radar return on high frequency X band radar, which is the radar frequency traditionally used for detection, tracking and terminal homing (because of its precision) that to track an F-22 requires the radar to track everything insect size and larger, which is too much. To categorise the insects and other things floating around like Clouds as noise is to also categorise the F-22 as noise so it becomes invisible.
    Effectively...Yes...But clarifications to follow...

    GarryB wrote:There was a similar problem a few decades ago with the An-2 biplane that the Soviets used as a light transport and also for dropping small teams of paratroopers.

    When flying low and slow a modern radar looking down would detect the plane but the plane would be hidden in the enormous radar reflection of the ground. To remove the ground as a reflector they simply used the doppler effect so anything that was not moving at 120km/h was removed from the radar display so that cars did not appear as targets. This meant that the An-2 flying at 90km/h also disappeared and so it was the first stealth aircraft!
    Sure...If the goal is to credit who has the first 'stealth' aircraft, then you can speciously claim said credit. But no one is going to take said claim seriously.

    GarryB wrote:The difference in this case is that instead of looking down into a huge reflection of the ground looking for an insect sized target you are looking up and let me tell you there are no insects above 10,000m let alone the 20,000m operating ceiling of the F-22. Another thing is that few insects fly at anywhere near the speed of the F-22 so actual insects and clouds and other things that might be mistaken for F-22s can be removed as noise if they are moving at less than 50km/h which should remove everything except for those super cruising F-22s.
    There is a grossly flawed understanding of 'clutter' in general. To start...No one knows what the Earth itself look like from a radar perspective because the Earth is covered with 'stuff', from flora to fauna and everything in between. A bird may have the same reflectivity as a rock that is smaller than itself. A shrub may have the same radar reflectivity even though its volume is ten times larger than both bird and rock. Cumulatively, we have 'ground clutter'. To filter out 'ground clutter' is to filter out anything that falls within a certain reflectivity range that made up 'ground clutter', including the Doppler components of any object within that range. It is not difficult to understand the argument that: No movement, no Doppler component, and in order to exploit the Doppler component of a moving object, you must be focused on that object in the first place, and in order to focus on one or more objects you must be able to distinguish them based upon some criteria.

    Moving on...A 'decibel' is a base 10 difference between two power levels.

    http://www.howstuffworks.com/question124.htm
    On the decibel scale, the smallest audible sound (near total silence) is 0 dB. A sound 10 times more powerful is 10 dB. A sound 100 times more powerful than near total silence is 20 dB. A sound 1,000 times more powerful than near total silence is 30 dB.
    So we should see this scaling:

    http://upload.wikimedia.org/wikipedia/en/a/a0/X_and_log_x.svg

    If the bird has a .05db difference over the rock and this difference falls within the rejection threshold because the radar equipment is not capable of separating out objects with this difference level, then it does not matter if the bird is flying, hence having a Doppler component, and the rock is on the ground, hence having no Doppler component, because both will be classified as 'clutter' and rejected. If the radar equipment is capable of separating out objects down to .0000000000005db difference, which would make it a really outstanding piece, then we can have different levels of rejection thresholds. We can filter out individual leaves, one leaf that is swaying in the wind and one that is still. We can see bird's Doppler component when it is moving on the ground next to the rock and certainly when it is in flight.

    Often, when biologists 'sees' insects on their radar scopes, they do not see distinct units but rather the swarm itself, be it locust or the annual Monarch butterfly migration. This is only a reinforcement of basic radar reflective behavior. The radar signal, as a conical beam that expands with distance, reflect off individual insect (or bird) and this reflection in turn reflect off another insect (or bird) in the mass and so on. The effect is also called 'reverberation'. The result is that for insect swarms or flocks of birds, radar detection is usually volumetric, meaning the detection is based upon the cumulative effect from all the reflections inside the insect swarm or the flock of birds. Same idea for a tree. The radar signal will have multiple reflections off the individual leaves and the result is an electronic 'tree'. If a single insect drop out of the swarm, a single bird drop out of the flock, or a single leaf fall off the tree, each will NOT be seen by the radar. This type of clutter is called 'volume clutter': insect swarms, flocks of birds, flora, or various meteorological phenomenon such as rain/snow fall.

    http://www.fighter-planes.com/info/f111_aardvark.htm
    The F-111's automatic terrain-following radar system flies the craft at a constant altitude following the Earth's contours. It allows the aircraft to fly in valleys and over mountains, day or night, regardless of weather conditions. Should any of the system's circuits fail, the aircraft automatically initiates a climb.
    There were many F-111 sorties that came back with green evidences on an aircraft's underside. What happened was that even though the hill itself is full of trees and they contributed to a volumetric RCS that follows the hill's contour, one tree stands alone, or it was tall enough to stand out from the rest, so it was not detected and the aircraft clipped it as it flew over the hill top. This was rare but not unknown in the F-111 community. When such 'accidents' did occurred, it was always at very low altitudes and under TF 'Hard' setting.

    A volumetric RCS can have two Doppler components: from itself as a moving volume, and from the individual units. But if any unit is detached from the volume, its Doppler component will be lost to the seeking radar unless the radar is capable of distinguishing this unit in the first place.

    Centimetric freqs can distinguish individual insects, even within a swarm, BUT only at a few hundred meters.

    http://onlinelibrary.wiley.com/doi/10.1111/j.1744-7917.2003.tb00359.x/abstract
    The recent development of automatically operating, inexpensive vertical-looking radar (VLR) for entomological purposes has made it practical to carry out routine, automated monitoring of insect aerial migration throughout the year. In this paper we investigate whether such radars might have a role in monitoring and forecasting schemes designed to improve the management of the Brown Planthopper (BPH), Nilaparvata lugens, and of associated rice pest species in China. A survey of the literature revealed that these insects typically migrate at altitudes between 300 to 2 000 m above ground level, but calculations based on BPH radar scattering cross-sections indicated that the maximum altitude at which they individually produce signals analysable by current VLRs is only ˜ 240 m. We also show that coverage over most of the flight altitudes of BPH could be achieved by building a VLR using a wavelength of 8.8 mm instead of the 3.2 cm of existing VLR, but that such a radar would be expensive to build and to operate. We suggest that a more practical solution would be to use a 3.2 cm VLR as a monitor of the aerial movement of the larger species, from which the migration of rice pests in general might be inferred.
    Translation: We can use cm and mm wavelengths to detect individual insects but only out (or up) to 240 meters. For the Brown Planthopper (BPH), each bugger weighs about 1-2mg and 2-3mm in body length. Using wavelength 3.2cm of the standard X band radar...

    http://en.wikipedia.org/wiki/Radar
    X 8–12 GHz 2.5–3.75 cm Missile guidance, marine radar, weather, medium-resolution mapping and ground surveillance; in the USA the narrow range 10.525 GHz ±25 MHz is used for airport radar; short range tracking. Named X band because the frequency was a secret during WW2
    ...We have an estimated RCS of 2x10-4 cm/squared at 200-300 meters distance PER BUG. Beyond this distance and the radar will have to rely upon the volumetric density of a BPH swarm to know if there are any BPH aflight. Millimetric freqs are better but this wavelength matches the diameter of individual rain drops. The result is that a mm wavelength signal will be intercepted by rain drops or anything similar before the signal can pick up any bug. This is why the mm wavelengths are usually confined to laboratory and/or highly specialized detection schemes outside of military applications.

    The X band is centimetric but it does not matter the radar perspective, up or down looking, the distance involve between radar and aircraft renders the F-22 extremely difficult to create any statistical analysis by the seeking radar. As if looking up is not bad enough, there is the proverbial 'double whammy' if the radar is in a 'look down' perspective in that: Not only must the radar deal with a volumetric density that could be dismissed by itself but also that this volume's RCS is part of the 'ground clutter' rejection threshold.

    Clutter is from radar echoes. Noise is NOT clutter, is independent of clutter, can exist without clutter, is hardware related, and is usually affected by time and temperature. Clutter + Noise = Interference. The F-22's RCS signal level is well within the clutter rejection threshold OR internally generated noise. So even if there are no flock of birds or swarms of insects around, odds are excellent that a radar system's own noise already blanket the F-22. The argument that the F-22's Doppler component will give it away despite its 'insect' or 'bird' level RCS came from a flawed understanding of radar detection, clutter types, and noise.

    Still think you can detect the F-22?

    GarryB wrote:Another issue is of course that the shape of an aircraft only matters to radar that can actually detect shape like X band radar. L and N band radar resonates of the aircraft as a single pulse and detection range is not effected by shaping at all so a wing mounted L band radar that can detect an Su-27 at 400km can detect a T-50 or an F-22 at 400km too.
    No radar signals detect any 'shape'. The entire paragraph is absolutely nonsensical.

    GarryB wrote:That is why they haven't wasted billions making the T-50 super stealthy... there will be no point in 20 years.
    They did not waste any billions because they did not know how to build a 'stealthy' one.

    GarryB wrote:Regarding the shooting down of the F-117 lets put it in perspective.
    Yes...We should.

    GarryB wrote:It was NATO vs Serbia. NATO that looks on paper to be the most powerful military force the world has ever seen vs Serbia.
    Does not matter if it was NATO. An irrelevant argument.

    GarryB wrote:The F-117 was claimed to be completely invisible, undetectable.
    No one claimed so.

    GarryB wrote:It was going to go into the Soviet Union in the 1980s completely undetected but an enormous range of radars large and small and evade S-300 and S-300V SAM sites and Mig-31 interceptors and Su-27 fighters (note both with IRST sensors) and drop laser guided bombs on very high priority targets and then fly home in safety despite thousands of enemy fighters patrolling the skies etc etc etc.

    If the shoot down was luck then why didn't the Iraqis get some too?
    Because the Iraqi air defense was not so fortunate? Fortune and probability are not the same thing.

    GarryB wrote:If you can base an air defence around luck why waste money on guided SAMs when unguided Grad rockets are much cheaper... just fit them with airpresure fuses so they explode at certain heights and fire barrages everytime you hear an aircraft engine?
    Who said anything about using fortune as a basis for defense? Again...Fortune and probability are not the same thing. This argument is based upon a flawed understanding of fortune versus probability.

    GarryB wrote:Try this.
    Get a digital camera and go out into the middle of nowhere that is under the flight path of an airport but far enough away from any airport so that all the aircraft are at 10,000m or so (ie 30,000ft would be a normal operating height for an airliner) so you can't hear its engines.
    Close your eyes and get your map out and look up the flight schedule and work out, based on airspeed and time when the next aircraft flys over.
    Using that fly over time you can take 30 shots of the sky but only planes caught in the dead centre of the picture count.
    You have to take the photos with your eyes closed and you are not allowed to look for aircraft before or even after you take the photos.
    Now do it again... at night.
    Luck my a$$.
    They wouldn't have been able to mass large numbers of SAMs to fire at the F-117 simply because a large group of SAMs would be detected and destroyed.
    Nonsense. Currently, once a SAM is in flight, all an aircraft can do is evade, not try to shoot the missile. Perhaps what you mean is that the launchers would be destroyed? This argument ignored history, particularly the North Vietnamese air defense networks.

    GarryB wrote:They probably only had one or maybe two launchers so that means about 6 shots maximum at the target... and if you can't see the target your chances of hitting it with even 6 shots is so close to zero it is not worth the effort.
    By this logic, all soldiers should be superb marksmen, one-shot-one-kill. After all, if a soldier need to shoot off several rounds to increase his odds of hitting his target and with no guarantees to boot, it is not worth the effort of shooting.

    GarryB wrote:The reality is that the F-117 was not invisible,...
    The US never claimed it was. This is a weak argument in trying to downplay the its effectiveness.

    GarryB wrote:...what they probably did was illuminate the target with the radar of another battery from behind where the F-117 was coming from and so the radar emissions scattered from the target away from the emitting antenna would be reflected towards other batteries based in other places.
    Probably...??? This is called a 'bi-static' radar configuration. Some air defense training call it 'electronic bracketing'. Your usage of the word 'behind' is indicative of a highly speculative argument. In a bi-static configuration, the reflection off a body that is from another transmitter is used by a physically and geographically distinct receiver to determine if the target produced a valid return. There is no 'behind', only approach direction. The catch for an effective bi-static radar attack, or bracketing, is that both stations must be in sync with each other as to when the transmitter will go active, its transmit freq, and the direction of the transmit.

    The radar cross section (RCS) valuation of any body is essentially a 'fictitious' argument. This valuation is a 'fiction' in the sense that if no radar then no RCS. If the distance changes, then the RCS value changes. Same for freq employed, or transmit mode, such as pulsed or continuous wave (CW). The bi-static RCS of any object is always greater than its mono-static RCS but this assume that the F-117 was ALREADY under radar capture and its bi-static RCS is being used for greater odds of a successful SAM intercept. This is too much of an assumption that we cannot take it at face value.

    GarryB wrote:This means several things... first it means they knew what the target was going to be... not rocket science... they were there to defend something so they knew what the target of any plane in that area was.
    You need to clarify the context of the word 'target' here. From an air defense perspective, the 'target' is an attacking aircraft. From the attacking aircraft's perspective, the 'target' is whatever on the ground that has some value. Lack of proper context rendered this argument worthless.

    GarryB wrote:Second it means they knew the direction it was coming from, which again is a no brainer because I am sure they would have taken steps to determine where NATO deployed its aircraft to and which were where.
    After several attacks it would be a 'no brainer'. Nothing spectacular from the Serbian air defense here.

    GarryB wrote:Third it means that there was a spy at the NATO base who watched the F-117s take off to pass that information on to the Serbian air defences... not really a surprise.
    This has been established. Still no 'Wow' factor here.

    GarryB wrote:Fourth... and most importantly they would need to aim the guidance beam at the F-117 and keep it on it for the missiles to guide.
    Guidance beam? This is still under the assumption that the F-117 was detectable in the first place. Too speculative.

    GarryB wrote:These SA-3s are not vanilla old models they have had upgrades and those upgrades probably included optical backup guidance which was probably used by the first unit to mark the aircraft with a pencil radar beam.
    Probably? We need something more concrete. Else the default position is -- no.

    GarryB wrote:I rather doubt luck is why the F-117 was brought down, that would take a lot of organisation and coordination.
    The 'luck' here is not about how the Serbian air defense was able to exploit NATO's predictability, although it is commendable that they did. The 'luck' here is that several missiles were launched and one of them successfully damaged the aircraft. The tactic is not new and is called 'spray and pray'.

    GarryB wrote:The reason the Serbs didn't seem to do very well with only two confirmed kills is simply because NATO was so scared it operated above the effective altitude of most Serbian systems. Another factor often ignored in the west is that the west used a lot of unmanned platforms and they lost something like 50 of those during the campaign.
    Utter BS. Wild Weasels continued to harass the Serbian air defense at within SAM range. If whatever it was that Zoltan Dani did to make it so effective against the F-117, it should have been a hundred times more effective against these Wild Weasels fighters. The UAV combat loss is nothing more than red herring argument.

    GarryB wrote:If the Serbian Air Defence Force failed because it only brought down 2 manned aircraft then the all powerful NATO force failed because after 74 odd days of total air superiority and air domination it completely failed in its mission to defeat the Serbian armed forces, and the Serbian air defence forces were as dangerous to NATO aircraft on day 74 as they were on day 1.
    The air campaign did what it was supposed to do -- control the air space. To defeat the Serbian military it would have required a ground campaign. The dispute is not about whether the Serbian air defense was successful or not. The dispute is about the ridiculous claim that the F-117 was effectively detected, tracked, and targeted.

    GarryB wrote:Sounds like a fail fail fail for NATO to me.
    Sounds like a fail fail fail argument for the Serbian air defense to me.

    GarryB wrote:In the end NATO had to resort to lying to Russia to make it think it would have a role in the peacekeeping afterwards to get the Serbs to sign and when the Russians found they had been double crossed they raced forces to Pristina.
    The US General in charge reacted by ordering the local British forces to take Pristina, by force if necessary... to which the British General Michael Jackson (no joke... look it up) told him to get stuffed, that he would have to work with the Russians and he wasn't going to start WWIII over this.
    Sensible chap IMHO. (The brit, not the yank).
    This is a political argument.

    GarryB
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    Re: PAK FA, T-50: News

    Post  GarryB on Mon Sep 20, 2010 12:38 pm

    So what? How does this proved the F-15's design to be based upon the MIG-25? It does not.

    The Soviets fly a prototype with a specific planform and layout that has not been used previously.
    The US develops a counter aircraft with exactly the same unique planform.

    When it happens the other way around it is called copying.

    Boyd's Energy-Management Theory for air combat predated the MIG-25 and it heavily influenced the development of the F-15 and F-16.

    So? When the Soviets developed their space shuttle they were heavily influenced by the US Space Shuttle... NASA spent 2 billion designing the external shape of the shuttle so the Soviets adopted that shape with a few minor changes, but the conceptual design is totally different. The US Space shuttle is designed to be a very heavy aircraft with an enormous fuel tank that needs two solid rocket boosters to get airborne. The reuse of the fuel tank and various other design choices makes a US Space shuttle launch incredibly expensive.
    The Soviet design is a glider that sits on a rocket to get into space. No nasty toxic and incredibly expensive solid fuel boosters... and the rocket can be used to take up 100 ton payloads by leaving the shuttle on the ground if necessary which the US Space shuttle can't do.

    The F-111's first flight was in 1964 and eventually it failed to impress the US Navy, who took its TF-30 engines and built those engines into the F-14, which had its first flight in 1970.

    The F-111 looks nothing at all like a Mig-25 which flew in 1964... early enough to influence both the F-15 and F-14.

    The USAF was determined to have its own air superiority fighter that was independently developed from any Navy project, hence the F-X being the F-111 derivative. The original F-X was supposed to have swing wings like the F-111 and the F-14.

    The F-111 was too heavy to be a navy fighter and was converted into a heavy strike aircraft with its radar and missile evolving into the F-14 radar and missile.
    This doesn't change the fact that when the US saw the Mig-25 their response was the plane we know now as the F-15 which is rather more like the Mig-25 than the F-111 or any other US aircraft previously seen.

    Given the fact that one of the F-15's missions is to be a high altitude and Mach capable interceptor, and the MIG-25 was supposed to be that high altitude and Mach capable interceptor, any visual similarities between the F-15 and the older MIG-25, are coincidental, not intentional, and quite superficial.

    Nice try but the F-4 was already a capable supersonic interceptor so it wont wash.

    What made the F-15 a superior aircraft over the MIG-25 was of Boyd's EM theory and US technology lead.

    What made the F-15 a superior fighter is that it was designed as a fighter.
    What made the Mig-25 a superior interceptor was that it was designed to accelerate to mach 2.5 and fly at that speed out to a target and shoot at that target with very long range missiles using a very powerful but optimised radar and then fly back to base at mach 2.5.
    The F-15 might reach mach 2.5 for 3 minutes but it will not fly all the way to its target and back at such speeds.

    Many would like to believe that the US copied the MIG-25 into the F-15 but the facts says otherwise.

    No. The facts do not say otherwise. The fact that Boyd is considered the father of the F-15 yet if he had actually designed it it would be an F-16 suggests that the Mig-25 was the basis for the F-15 against his wishes!
    The USAF wanted a big powerful twin engined heavy high mach fighter plane that they assumed the Mig-25 was. That led them to the F-15. As you say if the so called father of the F-15 had had his way it would have been barely able to fly mach 2 with a single engine and single fin, two wingtip missiles and a gun and a good radar.

    Based upon known radar practices. That still does not negate the fact that the US never claimed anything to be 'invisible' to radar detection.

    So claiming enemy air defence radars can't detect it means what? I would thing not visible to radar. Another way of saying that is invisible to radar detection. Or has the English language changed?

    Technically speaking, there are no such things as 'high' or 'low', but there are such things as 'higher' or 'lower'.

    The EM spectrum includes a wide range of frequencies that include visible light. I would say that short wavelengths relate to high frequencies and long wavelengths relate low frequencies. I could be very precise and mention bands... in fact to be fair I believe I did. I called the 3 antennas in the nose of the T-50 X band AESA high frequency radars and the wing mounted L and N band AESA radars as being longer wavelength lower frequency radars. Considering the number of fighter aircraft with radars of L and N band or lower (ie pretty much 0) I think it is fair to call such band radars low frequency radar even though they are not that far apart on the EM spectrum.

    Your argument centered around the phrasing 'high frequency' which give the readers no valid references, whereas the words 'decimetric', 'centimetric', and 'millimetric' are far more accurate descriptors.

    Sure, I would be happy to use such descriptors. The X band is 2.5cm to 4cm wavelength, L band is 15cm-30cm, but what is N Band? Clearly longer than 30cm but how much longer and what range of length. This puts L and N band in decimetric, and X band in Centimetric.

    Millimetric bands are nowhere as efficient as centimetric bands for general purposes and even less so than decimetric bands.

    For targets surrounded by severe clutter like a tank dug in to a hillside surrounded by trees and grass etc it is the only radar option. The only problem has been range and considering the MMW radar on the Mi-28N will detect a tank size target against a ground background from 10-12km I think the range problems have been solved. The Mi-28N also uses a mast mounted CM wavelength radar for air targets because of its extra range but the Ah-64D Apache uses MMW only AFAIK.

    And you are wrong. This argument wrongly assume that it is less expensive to produce a radar low observable aircraft than a BVR missile.

    You are wrong. You need to develop BVR missiles no matter what. There is no reason to waste money on a radar low observable aircraft.

    The USAF could get by if all their F-22s suddenly disappeared. If all their AMRAAMs and SPARROWs and Phoenix's disappeared however I think I know what they would develop first and it wouldn't be an F-22 replacement.

    So yes, the wing leading edge arrays are indeed smaller than what is normally employed.

    You misunderstand. Look at the posted drawing above, the array is depicted near the wing tip on the leading edge of the wing and is quite short. For all we know it might be located near the wing root so that the angle of its positioning allows for both arrays to see a target dead ahead of the aircraft. This could be used in a way that if a target is detected in L band but not in X band the aircraft could turn till both arrays can see the target which shouldn't be too hard with the directional information already provided. Active emissions from the L band radar will give a range accurate enough to fire a heat seeking missile with lock on after launch capability. The R-27ET does not have that capability, but to use an internally fired IR guided AAM they will have to develop such a capability. Once they have developed a short range AAM with lock on after launch capability is it no problem to fit that seeker and guidance to an R-27ET with an intertial navigation system to get it to the target area...

    The wing leading edge radars have limited usage and therefore limited efficacy.

    Together with a powerful nose mounted X band radar and IRST on both the Su-35 and the T-50 it will be part of a tool set that will likely give the pilot an edge they can either take advantage of or ignore.

    Never said so. What was said was that the US is currently not facing any F-117 equivalent, let alone an F-22 peer. And the F-117 is retired.

    In less than 5 years it could be facing stealthy UAVs like Migs "SKATE" yet BVR missiles it would need to deal with such a threat are not even on the drawing board.

    Wrong. Sonar is not a passive sensor. Just like radar, it is an active sensor. You know about the classic 'Ping', right? Watch 'The Hunt For Red October' again.

    Hahahahaha... you use "Hunt for Red October" as an example of Sonar technology?

    Submarines do not operate in a vaccuum, a Seawolf has had trillions of dollars spent on it to make it as quiet as possible yet in order for it to sink an enemy sub it must broadcast its presence with a ping like a WWII destroyer?

    When countries report the presence of a specific model submarine in their waters and lodge a protest do you think it was a ping they used to identify the target?

    How do they find targets? Ping continuously and listening to the noise bouncing off thermal layers and the sea bed to create a 3 D image? Or do they slow down and be as quiet as they can and listen to the noises made by other vessels and use its own slow movement and timed recordings of the sound source along with triangulation to work out the position in addition to a rev count of the targets propeller to determine speed?
    Sonar is very much like radar in the sense that in the real world it spends most of its time listening. The difference is that a Sonar is only used actively very rarely if at all.

    With infrared sensor, you can only tell if he is standing on your left side but not if he is facing you. Infrared emission still has to obey the laws of physics where energy decreases with distance: inverse-square law.

    Based on the IR signal you could roughly estimate range, but that is not important because the precise angular positioning of the target is all you need in a Soviet jet fitted with IRSTs. The Mig-29 and Su-27 and Mig-31 for that matter have their IRSTs and radars and helmet mounted sights all linked. This means a target detected by IRST can be ranged by radar without needing to scan to find the target. A fraction of a second ranging pulse to determine range and due to doppler shift in the beam you can also determine whether it is getting closer or further away from you.

    This is why IR sensor equipped missiles should still be looking at a strong heat source, like the jet exhaust, instead of a head-on view. It is not impossible but just very difficult for an IR missile to use wing leading edge sources. If anything, sunlight glinting off the canopy is a much better IR source.

    You are a couple of IR missile generations out of date. The very first missiles locked on to the hottest thing they could see. Very easily fooled by flares they were. Later they went to seekers that locked onto something that was not the hottest part of the aircraft so they developed flares with varying temperatures. Then they went for patterns of IR emissions so flares started getting released in bunches.
    Now they have IR seekers that use thermal images of the target that looks like a black and white photograph of the target and they can lock their missiles on any part of the target including the canopy. That is where we are today. The current defence is DIRCMs.

    Say what? The Iraqi air defense thought low radar observable capability effective enough.

    Even if the US had no stealth aircraft the result would have been the same.

    Completely nonsensical statement.

    I didn't make it. I was testing the logic by substituting a different subject.

    Considering how you do not know basic radar detection principles, you flunk your own test.

    You sound upset. Please explain which basic radar detection principle I got wrong before you give me that fail.

    It just need to stay effective long enough. But as long as no one can produce a countermeasure then we remain in the advantage.

    Yes... the F-22 is the most effective anti IED ever invented.

    Perhaps when you realise the cold war is over and your ability to WIN just leads to to getting into senseless wars... never mind. Merica strong!
    pirat

    Like it or not, 'stealth' works and works very well.

    It works well because F-117 flights are routed around things that will detect it. It works well because the US has a lot of satellites looking for large radar sites and has lots of planes snooping to find frequencies etc etc. Lots of planes with designations starting with RB got shot down and men killed to get that valuable information... so that the US can do the opposite of what its morals and ideals say it should. Sad

    Wrong. Radar detection is essentially a statistical process. Even if you can visually acquire an F-22 with your own eyes, that does not mean your radar can. Radar detection is statistical in the sense that if ten pulses impact an aircraft and only two echoes are produced, the system will reject these two echoes as anomalous. You can force, or reprogram, the system to accept two out of ten but that would mean you will spend so much time and expend so much effort in chasing after false positives, aka 'ghosts', that eventually you will go bankrupt or too exhausted to respond when a true positive attack your position. Raise the threshold to five out of ten and there will be less work. There are plenty more details about this process but for now, it is sufficent to say that the B-2, F-22, and F-35 are designed to deny the enemy that consistent statistical analysis.

    Context my friend. I was talking about IR signature of a supercruising F-22. Its having to maintain its position inside the battlespace means it can't simply fly in one direction, and that orbiting maximises its own radar coverage, but also means that an IR sensor looking for it will get it facing it every once in a while.



    Sure...If the goal is to credit who has the first 'stealth' aircraft, then you can speciously claim said credit. But no one is going to take said claim seriously.

    The USAF takes that claim seriously. The North Koreans planned to use to slow low flying An-2 to drop paratroopers over the south. They even made dedicated versions with the metal skin replaced with canvas to reduce RCS. Not all stealth is high tech.

    The Soviets also developed a prototype invisible aircraft that was made of a type of glass. From a distance the effect was apparantly quite effective, but over time cracks appeared and rendered the invisible effect less effective. That was during WWII.

    There is a grossly flawed understanding of 'clutter' in general.<snip>guish them based upon some criteria.

    What are you getting at? A downward looking radar scans its field of view and gets an enormous return from all the bits and pieces on the ground that reflect radar waves. A computer processes the return signal and ignores everything that is not moving faster than a set speed. This means it ignores grass moving in the wind or trees swaying in the wind or birds flying. Everything that is moving above a set speed is displayed on the radar screen. Why do you feel the need to make it more complicated than that? Of course I know it is more complicated than that but this thread is about the T-50, not radar technology.

    Still think you can detect the F-22?

    Your mistake is that you are using a tool the F-22 was precisely designed to evade to detect it. Using a long wave radar the F-22 isn't the size of an insect... it is the size of an F-22.

    No radar signals detect any 'shape'. The entire paragraph is absolutely nonsensical.

    To suggest radar signals are not effected by shape is to suggest that the shaping techniques used on the F-117 and F-22 and B-2 have nothing to do with reduced RCS.

    They did not waste any billions because they did not know how to build a 'stealthy' one.

    Ahh, so now they don't understand the physics of stealth... even though a Russian invented the mathematics that makes it possible? Till the US got their hands on their algorithms they were making models and making guesses to design stealth aircraft... an incredibly slow process with no guarantee of success.

    Does not matter if it was NATO. An irrelevant argument.

    Of course it matters. NATO is the west, the last remaining superpower and her cronies. Serbia should have been whipped in hours and not shot down a single aircraft. There should have been rows of burning Serbian tanks and apcs.

    Nonsense. Currently, once a SAM is in flight, all an aircraft can do is evade, not try to shoot the missile. Perhaps what you mean is that the launchers would be destroyed? This argument ignored history, particularly the North Vietnamese air defense networks.

    With all of NATOs surveillance assets there is no way a large number of large SAMs could be amassed near a target without it being noticed and attacked. There were planes flying over Serbia daily looking for something to bomb and returning home with bombs because they couldn't spot a target.


    By this logic, all soldiers should be superb marksmen, one-shot-one-kill. After all, if a soldier need to shoot off several rounds to increase his odds of hitting his target and with no guarantees to boot, it is not worth the effort of shooting.

    Strange twist of logic. But a blind soldier that can't see his targets could not rely on luck either. Not matter how many shots they took.

    You need to clarify the context of the word 'target' here. From an air defense perspective, the 'target' is an attacking aircraft. From the attacking aircraft's perspective, the 'target' is whatever on the ground that has some value. Lack of proper context rendered this argument worthless.

    It is clear from context that in this instance the target is the ground target and its relevance is in determining the location of the various SAM batteries that would be involved.

    After several attacks it would be a 'no brainer'. Nothing spectacular from the Serbian air defense here.

    Yet not luck either... it seems after fighting Iraq all this time they are used to fighting amateurs when it comes to mission planning.

    Probably? We need something more concrete. Else the default position is -- no.

    What is concrete is the wreckage of the aircraft shot down.

    The 'luck' here is not about how the Serbian air defense was able to exploit NATO's predictability, although it is commendable that they did. The 'luck' here is that several missiles were launched and one of them successfully damaged the aircraft. The tactic is not new and is called 'spray and pray'.

    And suddenly radar expert becomes fool. The SA-3 is a SARH, I assume you understand the principle. If a flight of 20 F-4 aircraft each carrying 8 SPARROWs all fired their missiles at a target 10kms away directly above them... that is 160 SPARROW missiles against an F-117 that was not being tracked or painted by radar exactly how many of those SPARROWs would hit? I mean really! attack

    Utter BS. Wild Weasels continued to harass the Serbian air defense at within SAM range. If whatever it was that Zoltan Dani did to make it so effective against the F-117, it should have been a hundred times more effective against these Wild Weasels fighters. The UAV combat loss is nothing more than red herring argument.

    And how many SAM sites were destroyed by these Wild Weasels that are designed to defeat SAM sites? Planes entering Serb airspace were no safer on the last day than they were on the first. Fail Wild Weasels.

    This is a political argument.

    It was a political war and historic fact.

    havok
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    F-15 TRUE HISTORY

    Post  havok on Tue Sep 21, 2010 2:45 am

    GarryB wrote:The Soviets fly a prototype with a specific planform and layout that has not been used previously.
    The US develops a counter aircraft with exactly the same unique planform.

    The F-111 looks nothing at all like a Mig-25 which flew in 1964... early enough to influence both the F-15 and F-14.

    The F-111 was too heavy to be a navy fighter and was converted into a heavy strike aircraft with its radar and missile evolving into the F-14 radar and missile.
    This doesn't change the fact that when the US saw the Mig-25 their response was the plane we know now as the F-15 which is rather more like the Mig-25 than the F-111 or any other US aircraft previously seen.

    No. The facts do not say otherwise. The fact that Boyd is considered the father of the F-15 yet if he had actually designed it it would be an F-16 suggests that the Mig-25 was the basis for the F-15 against his wishes!
    You have a problem understanding history here. Both the MIG-25's and F-111's first flights were in 1964. The F-111's failure as an air combat platform was quickly evident even before its first flight. Quick enough to make the USN rejected it on several reasons, least of all its 'saltwater' capability. If the F-X program intended the new air superiority fighter to be an improved F-111 derivative complete with swing wings, then it is not possible that the US learned of the MIG-25's planform on its first flight to copy it. As an aside, as someone who was in the right seat (WSO) of the F-111E, I can say that the F-111 itself was much more maneuverable than people gave it credit. If anything, it was highly probable that the Soviets, in designing the MIG-25, copied the North American A-5 Vigilante, which first flew in 1958...

    http://en.wikipedia.org/wiki/North_American_A-5_Vigilante
    Role Nuclear strike bomber, reconnaissance aircraft
    Manufacturer North American Aviation
    First flight 31 August 1958

    Although the Vigilante served in the attack and reconnaissance roles, its design and configuration was believed to be a major influence on one of the world's most famous postwar interceptors: the Soviet MiG-25 "Foxbat".[11] The MiG-25 would look even more familiar if the Vigilante had retained the twin vertical fins of the prototype; although North American originally specified two fins, that part of the design was vetoed by the Navy in favor of one folding tailfin. Dual tailfins would become part of the U.S. Navy's F-14 Tomcat, the US Navy's and U.S. Marine Corps' F/A-18 Hornet and the U.S. Air Force's F-15 Eagle and F-22 Raptor. The F-14, F-15 Eagle and other Western aircraft would also adopt a high mounted wing and wedge-shaped intake geometry (i.e., wedged air inlets) that were incorporated in the RA-5C.
    Most people either forgot or were ignorant of the A-5 and its shape. So look up the A-5 and compare it against the MIG-25 for yourself. Why should we copy the MIG-25's shape when we already have a high altitude and Mach capable shape in inventory to improve upon in the A-5? The F-111's swing wing for the F-X was an attempt to compensate for the A-5's low subsonic flight behavior. Like I said earlier, if there is a set of performance criteria required to accomplish a mission, the design must obey certain laws of physics and aerodynamics. The USSR had no SR-71 peer. Why not? It certainly was not because Soviet designers were stupid. The reason why the Soviets had no SR-71 peer was because they could not manufacture an aircraft with the same technology to achieve the same performance criteria. If the Soviets could, their version would look very similar to the SR-71.

    GarryB wrote:When it happens the other way around it is called copying.

    So? When the Soviets developed their space shuttle they were heavily influenced by the US Space Shuttle... NASA spent 2 billion designing the external shape of the shuttle so the Soviets adopted that shape with a few minor changes, but the conceptual design is totally different. The US Space shuttle is designed to be a very heavy aircraft with an enormous fuel tank that needs two solid rocket boosters to get airborne. The reuse of the fuel tank and various other design choices makes a US Space shuttle launch incredibly expensive.
    The Soviet design is a glider that sits on a rocket to get into space. No nasty toxic and incredibly expensive solid fuel boosters... and the rocket can be used to take up 100 ton payloads by leaving the shuttle on the ground if necessary which the US Space shuttle can't do.
    Both the US Space Shuttle and the Soviet Buran are multi-stage rocket vehicles. How each get the main craft into orbit is independent of the craft itself. In this, the Buran was truly a copy of the Space Shuttle and evidenced by the years spanned between the two as well as its shape. The Buran's first (and only) flight was in Nov 1988. The Space Shuttle's operational flights began in 1982.

    GarryB wrote:Nice try but the F-4 was already a capable supersonic interceptor so it wont wash.
    It was a nice try...To explain the true history of the F-15's development, not the false one that you would like gullible people to believe.

    GarryB wrote:What made the F-15 a superior fighter is that it was designed as a fighter.
    What made the Mig-25 a superior interceptor was that it was designed to accelerate to mach 2.5 and fly at that speed out to a target and shoot at that target with very long range missiles using a very powerful but optimised radar and then fly back to base at mach 2.5.
    The F-15 might reach mach 2.5 for 3 minutes but it will not fly all the way to its target and back at such speeds.
    The MIG-25's radar was 'optimized'? For what? If it was 'optimized' for anything, it was simply powerful enough to burn through some ECM tactics. As for its speed, if the engines had to be trashed after every Mach 2 flight, that made the MIG-25 severely limited in deployment. Do we need to review its combat radius...???

    http://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25
    Combat radius was 186 miles (300 km), and maximum range on internal fuel (at subsonic speeds) was only 744 miles (1,200 km) at low altitude (< 1000 meter).
    Sorry, buddy...But even though the world can mock US for grossly overestimating its capabilities, that was nothing compared to the shock that such a power like the Soviet Union can produced such an inferior product.

    havok
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    Re: PAK FA, T-50: News

    Post  havok on Tue Sep 21, 2010 9:15 am

    GarryB wrote:So claiming enemy air defence radars can't detect it means what? I would thing not visible to radar. Another way of saying that is invisible to radar detection. Or has the English language changed?
    It means that based upon 'current' radar technology and applications, the F-117 was effectively 'invisible' to any radar that operate under certain configurations. That does not mean we believe that the F-117 was truly invisible to radar. The English language has not changed but certainly your comprehension of it is lacking.

    GarryB wrote:The EM spectrum includes a wide range of frequencies that include visible light. I would say that short wavelengths relate to high frequencies and long wavelengths relate low frequencies. I could be very precise and mention bands... in fact to be fair I believe I did. I called the 3 antennas in the nose of the T-50 X band AESA high frequency radars and the wing mounted L and N band AESA radars as being longer wavelength lower frequency radars. Considering the number of fighter aircraft with radars of L and N band or lower (ie pretty much 0) I think it is fair to call such band radars low frequency radar even though they are not that far apart on the EM spectrum.

    Sure, I would be happy to use such descriptors. The X band is 2.5cm to 4cm wavelength, L band is 15cm-30cm, but what is N Band? Clearly longer than 30cm but how much longer and what range of length. This puts L and N band in decimetric, and X band in Centimetric.
    The L, N, or X bands do not tell the readers any more relevant information than 'high' or 'low' freqs. Those letters are merely groups, not characteristics, descriptors. Words like 'decimetric' or 'centimetric' give the readers far more information about a signal's characteristic, which is its wavelength. Am willing to bet that you did not know of these terms before I came on here.

    GarryB wrote:For targets surrounded by severe clutter like a tank dug in to a hillside surrounded by trees and grass etc it is the only radar option. The only problem has been range and considering the MMW radar on the Mi-28N will detect a tank size target against a ground background from 10-12km I think the range problems have been solved. The Mi-28N also uses a mast mounted CM wavelength radar for air targets because of its extra range but the Ah-64D Apache uses MMW only AFAIK.
    You are still talking about specialized applications of the mm wavelengths. Look at the distance: 10-12km. That is visual range. Because the mm wavelengths are borderline infrared, coupling infrared, a passive sensor, to generalize a heat source, and use radar, an active sensor, make a more precise target location, make sense.

    GarryB wrote:You are wrong. You need to develop BVR missiles no matter what. There is no reason to waste money on a radar low observable aircraft.
    Talk about bad reasoning. Here is the uncomfortable truth...

    http://www.acc.af.mil/news/story.asp?id=123041831
    Invisibility - even with eyes on

    When the Raptor finds itself in a dogfight, it is no longer beyond visual range, but the advantage of stealth isn't diminished. It maintains "high ground" even at close range.

    "I can't see the [expletive deleted] thing," said RAAF Squadron Leader Stephen Chappell, exchange F-15 pilot in the 65th Aggressor Squadron. "It won't let me put a weapons system on it, even when I can see it visually through the canopy. [Flying against the F-22] annoys the hell out of me."

    Lt. Col. Larry Bruce, 65th AS commander, admits flying against the Raptor is a very frustrating experience. Reluctantly, he admitted "it's humbling to fly against the F-22," - humbling, not only because of its stealth, but also its unmatched maneuverability and power.
    Yes...It is good to kill the enemy from as far away as possible. In exercises, we usually give %100 assurance to the missile, meaning that if a simulated missile is launched after a radar lock is announced, we consider it a valid 'kill'. In the real world, that would not be true, however, we do not want pilots to shoot at each other with live missiles in peacetime exercises, do we? So we defaulted to the missile. But if, as Chappell witnessed, that despite the F-22 being within visual range of the pilot, the F-22 still make it difficult for its enemy to get a radar lock, what make you think radar can get such a fix from beyond visual?

    GarryB wrote:You misunderstand. Look at the posted drawing above, the array is depicted near the wing tip on the leading edge of the wing and is quite short. For all we know it might be located near the wing root so that the angle of its positioning allows for both arrays to see a target dead ahead of the aircraft. This could be used in a way that if a target is detected in L band but not in X band the aircraft could turn till both arrays can see the target which shouldn't be too hard with the directional information already provided. Active emissions from the L band radar will give a range accurate enough to fire a heat seeking missile with lock on after launch capability. The R-27ET does not have that capability, but to use an internally fired IR guided AAM they will have to develop such a capability. Once they have developed a short range AAM with lock on after launch capability is it no problem to fit that seeker and guidance to an R-27ET with an intertial navigation system to get it to the target area...

    Together with a powerful nose mounted X band radar and IRST on both the Su-35 and the T-50 it will be part of a tool set that will likely give the pilot an edge they can either take advantage of or ignore.
    The array must be continuous. You make this argument because you do not know what an aircraft look like under its skin. I do. The wing leading edge is not continuous and the wing itself is not that thick. The thicker the wing, the increase of drag but increase of lift efficiency, helpful at TO/L speed. The thinner the wing, the faster the aircraft.

    http://www.ausairpower.net/APA-2009-06.html

    The above source which I posted earlier has images of how small these radar arrays are behind the wing leading edges and you seem to have a problem with the concept in radar detection that array dimensions affect detection range, beamwidth, and beam shape. This is not one continous array but of several small arrays. In a phase array antenna, individual transmit/receive (T/R) units must be precisely separated, usually wavelength dependent, and usually half wavelength apart. Another thing you do not seem to understand is that the antenna is NOT the array. The antenna contains the array. That mean this wing leading edge radar will be even smaller than what the leading edge implies. The wing leading edge may give the PRAT-FALL improved aximuth scan area but is hardly a reasonable response against US 'stealth' aircrafts. If anything, the F-22 will see this as a 'Here I am come get me' beacon by the PRAT-FALL and shoot it down without using its own radar.

    GarryB wrote:In less than 5 years it could be facing stealthy UAVs like Migs "SKATE" yet BVR missiles it would need to deal with such a threat are not even on the drawing board.
    Dream on.

    GarryB wrote:Hahahahaha... you use "Hunt for Red October" as an example of Sonar technology?

    Submarines do not operate in a vaccuum, a Seawolf has had trillions of dollars spent on it to make it as quiet as possible yet in order for it to sink an enemy sub it must broadcast its presence with a ping like a WWII destroyer?

    When countries report the presence of a specific model submarine in their waters and lodge a protest do you think it was a ping they used to identify the target?

    How do they find targets? Ping continuously and listening to the noise bouncing off thermal layers and the sea bed to create a 3 D image? Or do they slow down and be as quiet as they can and listen to the noises made by other vessels and use its own slow movement and timed recordings of the sound source along with triangulation to work out the position in addition to a rev count of the targets propeller to determine speed?
    Sonar is very much like radar in the sense that in the real world it spends most of its time listening. The difference is that a Sonar is only used actively very rarely if at all.
    The fact that you do not deny that sonar does transmit make the laugh on you. Radar and sonar contain structurally distinct sections: transmit and receive. If a submarine is 'noisy' in anyway, be it deliberate or accidental, it does not negate the fact that sonar does transmit, aka 'ping'. So your argument that sonar is a passive sensor is wrong. Just because a person listen (passive) more than he speaks (active) does not make him any less of a transmitter of audio signals.

    GarryB wrote:Based on the IR signal you could roughly estimate range, but that is not important because the precise angular positioning of the target is all you need in a Soviet jet fitted with IRSTs. The Mig-29 and Su-27 and Mig-31 for that matter have their IRSTs and radars and helmet mounted sights all linked. This means a target detected by IRST can be ranged by radar without needing to scan to find the target. A fraction of a second ranging pulse to determine range and due to doppler shift in the beam you can also determine whether it is getting closer or further away from you.
    Now who is the joke here? You speak as if the fighter's radar has 360deg capability. It does not. Or is Russia exempt from the laws of physics? If an infrared sensor detect a target that is outside of the radar's physical sweep (scan) limits, then all you have are less than ideal range estimation, and I know that it is possible to have IR target range estimation, and general target direction. If a missile is launched in that direction, it will be at a disadvantage because of the lack of initial target radar information. In exercises, we will give %100 assurance to the helmet mounted cueing system. But in the real world, things will be quite different.

    GarryB wrote:You are a couple of IR missile generations out of date. The very first missiles locked on to the hottest thing they could see. Very easily fooled by flares they were. Later they went to seekers that locked onto something that was not the hottest part of the aircraft so they developed flares with varying temperatures. Then they went for patterns of IR emissions so flares started getting released in bunches.
    Now they have IR seekers that use thermal images of the target that looks like a black and white photograph of the target and they can lock their missiles on any part of the target including the canopy. That is where we are today. The current defence is DIRCMs.
    And you are grasping at straws. The main reason why flares are released in salvos is because flares do not have the same aerodynamics characteristics as the parent aircraft. It does not matter if the IR sensor can distinguish gradients of IR emissions on a body if its sensor view is completety blanketed by a greater IR emission, be it from one or more flares. That is the goal of chaff and flares: To blanket the appropriate sensor's view for as long as possible. This is why aircrafts make violent maneuvers after these discharges.

    GarryB wrote:Even if the US had no stealth aircraft the result would have been the same.
    With the F-117, it was a better result.

    GarryB wrote:You sound upset. Please explain which basic radar detection principle I got wrong before you give me that fail.
    Not upset at all. Just amused at the lengths that some people would go in trying to downplay the effectiveness of low radar observability. As far as radar detection goes, you got all wrong.

    GarryB wrote:Yes... the F-22 is the most effective anti IED ever invented.
    Sarcasm about our stuff does not elevate Russian stuff.

    GarryB wrote:Perhaps when you realise the cold war is over and your ability to WIN just leads to to getting into senseless wars... never mind. Merica strong!
    The Cold War may be over but human conflicts continues. You are just upset that Russia is no longer as influential as when the Soviet empire existed.

    GarryB wrote:It works well because F-117 flights are routed around things that will detect it.
    Such as?

    GarryB wrote:It works well because the US has a lot of satellites looking for large radar sites and has lots of planes snooping to find frequencies etc etc. Lots of planes with designations starting with RB got shot down and men killed to get that valuable information... so that the US can do the opposite of what its morals and ideals say it should.
    Spare me your crocodile tears for our morals and ideals. Try to remain in the technical realm.

    GarryB wrote:Context my friend. I was talking about IR signature of a supercruising F-22. Its having to maintain its position inside the battlespace means it can't simply fly in one direction, and that orbiting maximises its own radar coverage, but also means that an IR sensor looking for it will get it facing it every once in a while.
    Once in a while? The F-22 is to achieve air supremacy...

    - Air dominance: The ability of an air force to compel other air forces to change their arrays and tactics, usually in favor of this air force, and without combat.

    - Air superiority: The ability of an air force inflict overwhelming losses to contestant air forces to gain control of an air space, leave the area, and return to achieve the same level of control over and over again -- without suffering losses that would degrade this ability.

    - Air supremacy: He flies, he dies.

    We achieved this without the F-22. You are dreaming with your IR sensors.

    GarryB wrote:The USAF takes that claim seriously. The North Koreans planned to use to slow low flying An-2 to drop paratroopers over the south. They even made dedicated versions with the metal skin replaced with canvas to reduce RCS. Not all stealth is high tech.
    You are confused between 'stealth' and 'low radar observability'. Understandable, however. For the former, flying below the radar horizon make an aircraft 'stealth'. Avoidance of radar capture is the goal. For the latter, the goal is the ability to influence how radar behaves on one's body. That ability can be deliberate or accidental. A Sopwith Camel would be quite difficult to detect and this is accidental as the designers did not know of radars. The F-22 and its brethens cannot be compared in anyway, not even in principle, to what you are talking about because your version of 'low radar observability' is a compromised version from the original with inferior performance. This is a weak argument against US 'stealth' aircrafts.

    GarryB wrote:The Soviets also developed a prototype invisible aircraft that was made of a type of glass. From a distance the effect was apparantly quite effective, but over time cracks appeared and rendered the invisible effect less effective. That was during WWII.
    Source please.

    GarryB wrote:What are you getting at? A downward looking radar scans its field of view and gets an enormous return from all the bits and pieces on the ground that reflect radar waves. A computer processes the return signal and ignores everything that is not moving faster than a set speed. This means it ignores grass moving in the wind or trees swaying in the wind or birds flying. Everything that is moving above a set speed is displayed on the radar screen. Why do you feel the need to make it more complicated than that? Of course I know it is more complicated than that...
    This is what I mean when I said you have a flawed understanding of radar detection. I cannot make it clearer: Doppler is a component of target detection. But if you already dismissed the target as part of clutter, then its Doppler component, if any exist, is also dismissed. The reason why moving target indicator (MTI) radar works is because the target was not so rejected. In other words, BEFORE the MTI indicator is active for a target, the radar system ALREADY considered it a valid target and displayed its Doppler component.

    GarryB wrote:...but this thread is about the T-50, not radar technology.
    When you begin to exaggerate the PRAT-FALL's radar capabilities, you made radar detection a parallel issue.

    GarryB wrote:Your mistake is that you are using a tool the F-22 was precisely designed to evade to detect it. Using a long wave radar the F-22 isn't the size of an insect... it is the size of an F-22.
    In order to truly make the F-22 'resonates' and therefore detectable you need to get down into the decimetric freqs and we are talking about meters length freqs -- the HF bands.

    http://en.wikipedia.org/wiki/Radar
    HF 3–30 MHz 10–100 m
    We knew of this from the F-117 days. But the problem with the HF bands is array dimensions, as in meters wide. Sorry...But the wing leading edge does not qualify because the word 'wide' here mean both width and height.

    http://www.argospress.com/Resources/radar/radarcrossectio.htm
    # Raleigh region. If the target is a lot smaller than the wavelength of the radar system, the target is said to be in the Raleigh region. If the target is in the Raleigh region, the radar cross section of the target tends to be smaller than the target's physical size.

    # Resonance region. If the target is of similar dimension to that of the wavelength, the target is said to be in the resonance region. In the resonance region, the radar cross section of the target may vary a great deal but tends to be larger than the physical size of the target.

    # Optical region. The optical region occurs when the target is much larger than the operating wavelength of the radar. This is quite often the case with operational radar systems whose wavelengths are normally in the order of centimetres in length. When operating in this region, the radar cross section of the target is similar to its physical size
    See the highlighted? So...If you want to resonate a Brown PlantHopper (BPH) bug whose body is 2-3mm in length and the same in diameter, then you need to use the millimetric freqs. If a centimetric (cm) freq is used, then the bug will be in the Rayleigh region where its RCS will indicate to be smaller than its true physical dimensions. Get it?

    For the F-22...Yes...Its physical dimensions are much larger than the BPH insect but even if the L (cm) band is used, the F-22's ability to affect radar wave behaviors on its body will still produce an RCS in the same 'insect' range. You bring up size, now you learned something new about the relationship between radar and size.

    GarryB wrote:To suggest radar signals are not effected by shape is to suggest that the shaping techniques used on the F-117 and F-22 and B-2 have nothing to do with reduced RCS.
    I 'suggest' no such thing. I was responding to YOUR claim in post 76...

    GarryB wrote:Another issue is of course that the shape of an aircraft only matters to radar that can actually detect shape like X band radar.
    Radars do not detect shapes whereas reflective areas on a body create radar echoes. Shaping affect those reflective areas. Your flawed understanding of radar detection made you jumped to that conclusion.

    GarryB wrote:Ahh, so now they don't understand the physics of stealth... even though a Russian invented the mathematics that makes it possible? Till the US got their hands on their algorithms they were making models and making guesses to design stealth aircraft... an incredibly slow process with no guarantee of success.
    No...The Soviets did not. I have Ufimtsev's text book. He moved to the US, taught electromagnetics at UCLA, and retired in the US. His book is not a 'cookbook' on how to create a low radar observable body. Ufimtsev was not surprised at all when the Soviets ignored his work, considering how the Soviets were quick to assign some degrees of military value to most academic products. No guarantee of success, you say? Then do explain why now everyone, from the Russian to the Chinese, are jumping on this 'stealth' bandwagon. Your desperation is hilarious.

    GarryB wrote:Of course it matters. NATO is the west, the last remaining superpower and her cronies. Serbia should have been whipped in hours and not shot down a single aircraft. There should have been rows of burning Serbian tanks and apcs.
    Your attempt to distinguish the US from NATO regarding the F-117 made NATO irrelevant. The F-117 was an American product, flown by American pilots.

    GarryB wrote:With all of NATOs surveillance assets there is no way a large number of large SAMs could be amassed near a target without it being noticed and attacked. There were planes flying over Serbia daily looking for something to bomb and returning home with bombs because they couldn't spot a target.

    And how many SAM sites were destroyed by these Wild Weasels that are designed to defeat SAM sites? Planes entering Serb airspace were no safer on the last day than they were on the first. Fail Wild Weasels.
    The fact that Zoltan Dani managed to launch several missiles meant that Wild Weasels missions were not %100 successful. This is funny. First you want to give Dani exaggerated technical credits, now you are trying to make it as if the Serbian air defense were completely helpless. Make up your mind.

    GarryB wrote:Strange twist of logic. But a blind soldier that can't see his targets could not rely on luck either. Not matter how many shots they took.
    If a soldier cannot see his target, he has no choice but to rely on luck. In any war, in any battle, there are always far more ammunition expended than bullets that hit an enemy soldier. The 'spray-and-pray' tactic is tried and true. Same for air defense missile training where multiple launches are advised even for a single hostile.

    GarryB wrote:What is concrete is the wreckage of the aircraft shot down.
    Yup...Just two out of tens of thousands of sorties. Not an air defense combat record to boast about. Not even for 'spray-and-pray' tactic.

    GarryB wrote:And suddenly radar expert becomes fool. The SA-3 is a SARH, I assume you understand the principle. If a flight of 20 F-4 aircraft each carrying 8 SPARROWs all fired their missiles at a target 10kms away directly above them... that is 160 SPARROW missiles against an F-117 that was not being tracked or painted by radar exactly how many of those SPARROWs would hit? I mean really!
    Who knows how many? But the issue here is result and two out of tens of thousands sorties is a sorry result.

    GarryB
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    Re: PAK FA, T-50: News

    Post  GarryB on Wed Sep 22, 2010 8:18 am

    You have a problem understanding history here.

    You mean your perception of history written by those you trust is more accurate than my perception of history written by those I trust?

    Both the MIG-25's and F-111's first flights were in 1964. The F-111's failure as an air combat platform was quickly evident even before its first flight.

    The first flight of the swing wing single tail fin F-111 is irrelevant.

    Its main problem was it was too heavy for carrier operation. The radar and missile and weapon system and even the engines seemed to work to a basic level in the F-14A.
    Seemed to work OK in the F-14D so if the F-111 had been made lighter I see no fundamental reason for it not to work if the same changes were made.

    If anything, it was highly probable that the Soviets, in designing the MIG-25, copied the North American A-5 Vigilante, which first flew in 1958...

    Except that a Tu-4 looks like a B-29 and the Soviet Buran looks like a Space Shuttle, and an R-3 looks like an early model Sidewinder. The Mig-25 looks quite unlike an F-111 or A-5 Vigilanete. The F-15 has the same layout as the Mig-25. The F-15 looks nothing like an F-111 or A-5.

    So look up the A-5 and compare it against the MIG-25 for yourself.

    I fail to see the similarity.

    Why should we copy the MIG-25's shape when we already have a high altitude and Mach capable shape in inventory to improve upon in the A-5? The F-111's swing wing for the F-X was an attempt to compensate for the A-5's low subsonic flight behavior.

    Because the plane they were working on was a failure, they see a Soviet plane and they need a plane to beat it and they have no time to develop it from scratch so they copy what they are trying to compete with. The exact same story for the Tu-4, the Sidewinder, and the Space Shuttle. The Soviets had 4 engined bombers in 1933. In fact the single engined ANT-25 flew 9,000km in 1937 to the US and that was what shocked the American congress into continuing funding for what was to become the B-17 which was going to be cut.
    Same with the Sidewinder, they already had their own missiles, but the Sidewinder was so different they had nothing like it. It was so simple and basic and modular that rather than wait 5 years for the concept of modular design to be absorbed in the AAM design industry they chose to copy the layout and design, though they used their own sensors and rocket motors, just like with the Tu-4 they used their own engines and defensive guns and bombs of course.

    The USSR had no SR-71 peer. Why not?

    They had plenty of mach 3 plus designs, mostly bombers. The main reason they were not built was because ICBMs were more promising and they would have no use for an SR-71 type aircraft. The Mig-25 recon model was good enough for most of their needs.

    The reason why the Soviets had no SR-71 peer was because they could not manufacture an aircraft with the same technology to achieve the same performance criteria. If the Soviets could, their version would look very similar to the SR-71.

    Interesting logic, but flawed. After looking at the heavy steel used in the manufacture of the Mig-25 western experts also claimed it was because of the backwardness of Soviet manufacturing technology and lack of skills with Titanium.
    The amount of Titanium used in one Alpha class sub could have made 1,000 Mig-25s.
    The Mig-25 met the requirements of the Soviets, they didn't care that it was heavy, or that it was cheaper to make.

    Both the US Space Shuttle and the Soviet Buran are multi-stage rocket vehicles. How each get the main craft into orbit is independent of the craft itself. In this, the Buran was truly a copy of the Space Shuttle and evidenced by the years spanned between the two as well as its shape. The Buran's first (and only) flight was in Nov 1988. The Space Shuttle's operational flights began in 1982.

    The Buran was much better system that was based on learning from the mistakes of the Space Shuttle. Every Shuttle launch was enormously expensive because those solid fuel rockets are very very expensive to run. Those large fuel tanks had to be recovered and returned to original shape and then thoroughly checked before it could be reused which is of course very expensive too. The 10 tons of rocket engine the Space Shuttle has in its rear end to burn all that fuel in the main fuel tank is dead weight for the rest of the flight.
    It was supposed to be cheaper but ended up being much more expensive. Each shuttle flight cost over 600 million dollars, compared to about 20 million to replace an ISS crew by Russian rocket. It is very useful for some missions and about 3/4 or Shuttle missions were military, but as a shuttle to move people to and from a space station it was a white elephant.
    Buran would be cheaper but not overly better than the shuttle for transfering crews. Where Buran would be totally superior is in constructing the space station itself. Simply by taking the Buran off the rocket and replacing it with 100 ton components to build the ISS they could have taken the entire existing station up in about 4 missions. Construction in space is enormously difficult and slow and making large components on the ground and taking them up in one piece would greatly speed up building the station and getting it operational.
    Unfortunately they only had the US Space Shuttle which cannot be seperated from the rockets that get it to space so you take up 90 tons of dead weight with a 10 ton payload. So 10 times more missions and long periods between missions fitting all the smaller components together in space.
    The Soviet copied the external aerodynamic shape but they clearly learned from the design faults of the US space shuttle to produce a clearly superior vehicle. Of course by the time it was ready there were economic problems and not being necessary it was amongst the first item to be cut.

    It was a nice try...To explain the true history of the F-15's development, not the false one that you would like gullible people to believe.

    So if they already had a Mach 2+ high altitude fighter what exactly made them suddenly want to develop a plane that looked like the Mig-25?
    Fear. They saw this plane at an airshow, which at the time they thought was the Mig-23 and from its layout they worked out it was a mach 3 fighter. They knew from intel that the Mig-23 was replacing the Mig-21 as the standard Soviet fighter so they copied the layout to ensure the performance would be similar and then they put in the best radar and best engines and best of everything they could manage to try to give their aircraft superiority because surely merican engines and radar and stuff would make it better. The problem was that it wasn't the standard fighter, it was a custom designed interceptor of very specialist design. Doesn't mean they didn't copy the external shell.

    The MIG-25's radar was 'optimized'? For what? If it was 'optimized' for anything, it was simply powerful enough to burn through some ECM tactics.

    Of course the radar was optimised... it was designed specifically for the aircraft for the interception role. It had no ground mapping or sea mapping capability. It was matched with the missiles and other systems for a specific role... it was optimised.

    As for its speed, if the engines had to be trashed after every Mach 2 flight, that made the MIG-25 severely limited in deployment. Do we need to review its combat radius...???

    The engines were fine up to Mach 2.85 and were only trashed when that speed was exceeded for more than a few minutes. The Mig-25 was used by the PVO air defence forces and were deployed to shoot down incoming US bombers so it is hardly surprising they weren't deployed to Frontal Aviation bases.
    Its combat radius was 10 times bigger than any other interceptor aircraft flying at faster than mach 2.

    Sorry, buddy...But even though the world can mock US for grossly overestimating its capabilities, that was nothing compared to the shock that such a power like the Soviet Union can produced such an inferior product.

    Hahahahaha... you are a funny guy. A 300km radius of action would be a mach 2.85 which is only matched today by one interceptor in service... the Mig-31.

    and maximum range on internal fuel (at subsonic speeds) was only 744 miles (1,200 km) at low altitude (< 1000 meter).

    And when would a Mig-25 operate at below 1,000m altitude? The Answer is twice... takeoff and landing. It operates normally at mach 2.5 plus and that can't happen for any aircraft below 1,000m.

    It means that based upon 'current' radar technology and applications, the F-117 was effectively 'invisible' to any radar that operate under certain configurations.

    It is very interesting that the first attacks of desert storm were attacks by low flying Apache helicopters on radar bases before the radar invisible F-117s entered Iraqi airspace.

    The L, N, or X bands do not tell the readers any more relevant information than 'high' or 'low' freqs. Those letters are merely groups, not characteristics, descriptors. Words like 'decimetric' or 'centimetric' give the readers far more information about a signal's characteristic, which is its wavelength. Am willing to bet that you did not know of these terms before I came on here.

    A reader that doesn't know what an X band radar probably wont be enlightened by being told it is a radar with a bandwidth inside centimetric wave band... or that the S band is also in that frequency range but the centimetric range is 100 times bigger than the milimetric range and the S band is a very small subset of that centimetric band. X, and L bands are more specific and precise than centimetric and milimetric bands. The AM band is a range of radio frequencies used to transmit AM radio, the FM band is a higher range that allows more information to be transmitted, including stereo signals. Telling someone the band width makes rather more sense than saying the signal is measured in centimetres or milimetres or tens of metres (ie decimetres). And if you take that bet you lose.


    You are still talking about specialized applications of the mm wavelengths. Look at the distance: 10-12km. That is visual range. Because the mm wavelengths are borderline infrared, coupling infrared, a passive sensor, to generalize a heat source, and use radar, an active sensor, make a more precise target location, make sense.

    Except that for an air to air missile visual range doesn't necessarily means the target is visible due to weather conditions like cloud or heavy rain. It is certainly not impossible to fit an Imaging infrared seeker together with a MMW radar seeker, but most of the time that will be redundant. You would need to analyse the expected results, of course you might find the IIR is good enough on its own, or that the computing power needed for the MMW seeker and its on board library of targets means another seeker will not fit. You could equally go the way the Russians have gone with one seeker head they have shown in public with an active radar homing seeker in the centre with passive radar sensors around the outer edge. The main radar seeker has a range of 20km in ARH mode but the passive sensors have a range of over 200km against an emitting target. Future seekers are likely to become multisensor.

    But if, as Chappell witnessed, that despite the F-22 being within visual range of the pilot, the F-22 still make it difficult for its enemy to get a radar lock, what make you think radar can get such a fix from beyond visual?

    He was in an F-15, perhaps if he was in a Mig-29 or Su-27, or for that matter a Su-35 he could use his IRST to get an initial lock or simply use his helmet mounted sight and lock an R-73 on the target.

    The array must be continuous.

    Why? The Zaslon-M radars of 4 seperate Mig-31s flying 200km apart are not continuous, yet their data can be combined into an antenna coverage 1,000km in width.
    The "failed" attempt to put a large radar in the nose and tail of a Nimrod aircraft to provide 360 degree coverage as an AWACS aircraft failed, but the fact that they tried suggests it is possible.

    You make this argument because you do not know what an aircraft look like under its skin.

    I make the arguement because from the photo of the array it is difficult to tell how long it would be or how many could be fitted to each wing.

    This is not one continous array but of several small arrays.

    And you are trying to correct me? It is one continuous array, the array consists like any array of array elements. An array of arrays would be each element in this case being an AESA radar on its own and it clearly is not.

    Another thing you do not seem to understand is that the antenna is NOT the array.

    As I mention above I know what an antenna is and that several radars can be linked together to make a larger antenna by using more and spaced arrays. Each Array is a collection of array elements.

    If anything, the F-22 will see this as a 'Here I am come get me' beacon by the PRAT-FALL and shoot it down without using its own radar.

    Hahaha... and a missile that guides to L band emissions would spell the end of stealth aircraft too... NATO operates it netcentric management system in L Band datalinks.

    Dream on.

    Of course... no one else in the world could ever develop a stealth UCAV. Russia can have stealthy cruise missiles but not stealthy UCAVs.
    BTW the performance of the SKATE will probably be comparable to the F-117 in that it will deliver two guided bombs in the 1,000-1,500kg range to about 2,000km flight radius at about 800km/h.

    The fact that you do not deny that sonar does transmit make the laugh on you.

    Active IR exists too... what is your point?

    Radar and sonar contain structurally distinct sections: transmit and receive. If a submarine is 'noisy' in anyway, be it deliberate or accidental, it does not negate the fact that sonar does transmit, aka 'ping'.

    And aircraft transmit IR radiation too... are you getting to a point any time soon?

    So your argument that sonar is a passive sensor is wrong. Just because a person listen (passive) more than he speaks (active) does not make him any less of a transmitter of audio signals.

    SONAR and RADAR and IR can all be passive and/or active. As a passive sensor sonar can determine range without being used actively. Just as my point was that IR sensors could also use the same or similar methods to be used passively to determine range. They can be accurate to within 1km and still be good enough because they are not being used for terminal guidance, they are being used to set up a shot.

    In both cases the weapon launched, whether it be a BVR AAM or a torpedo has its own seeker that might be active or passive that will take care of the terminal phase.

    Now who is the joke here? You speak as if the fighter's radar has 360deg capability. It does not. Or is Russia exempt from the laws of physics? If an infrared sensor detect a target that is outside of the radar's physical sweep (scan) limits, then all you have are less than ideal range estimation, and I know that it is possible to have IR target range estimation, and general target direction. If a missile is launched in that direction, it will be at a disadvantage because of the lack of initial target radar information. In exercises, we will give %100 assurance to the helmet mounted cueing system. But in the real world, things will be quite different.

    What I mean is if a pilot detects a target on his IRST he doesn't need to scan the entire sky with radar to find the target as this will give his position away to all aircraft nearby. He just needs to direct a ranging pulse of radar at the target and use the return information to determine range and closing speed. If he has to manoeuvre to get the target inside his radar field of view I am sure he will bother to take the time for the information it will deliver. I would suggest that considering the R-27ET is reported to have an air to air head on range of about 60km at medium to high altitudes that if the IRST has detected the target it will not likely be much further than that away from the launch aircraft and is worth a shot especially if the target didn't appear on radar before.

    The main reason why flares are released in salvos is because flares do not have the same aerodynamics characteristics as the parent aircraft.

    ? So. Do you think the incoming missile sees the salvo of flares and things... oh oh that isn't flying like a plane... I will ignore it.
    I think you Americans have taken your own terminology too far... smart weapon indeed.

    I stand by what I said originally.

    It does not matter if the IR sensor can distinguish gradients of IR emissions on a body if its sensor view is completety blanketed by a greater IR emission, be it from one or more flares. That is the goal of chaff and flares: To blanket the appropriate sensor's view for as long as possible. This is why aircrafts make violent maneuvers after these discharges.

    A modern IIR seeker like on AIM-9X creates an image like a thermal imager that is not fooled by lots of hot points of flares. Even the R-73 had a UV filter that could determine that a burning flare emitting UV energy was not an aircraft surface... which of course does not emit UV radiation... unless it has 60,000 V running through it then it might like high tension power cables.

    With the F-117, it was a better result.

    3 cruise missiles would give you the same result without risking a pilot and for a fraction of the cost.

    Just amused at the lengths that some people would go in trying to downplay the effectiveness of low radar observability.

    I just think it is over rated. But then most American things are overhyped, but perhaps that is because of the sophisticated American marketing capacity... in other words it is not a fault it is just something else you are better at than anyone else...
    Rolling Eyes

    Sarcasm about our stuff does not elevate Russian stuff.

    I don't need to elevate Russian stuff. You missed the point completely.
    F-22 is a cold war aircraft optimised to fight the cold war. Its job is to breach Soviet air defences and clear the skies of Soviet aircraft so that NATO aircraft can have their way.
    Your current problems however seem to be rather different and the F-22 has no role in either Iraq, Afghanistan or Iran.
    And before you say the F-22 could be used to strike Irans WMD program I would say that was the dumbest suggestion I have heard all week. A US or Israeli attack on Iran would be the most painful stab in your own foot that you could possibly think of short of shooting your own troops yourself.
    (Can I just say that up until now what the US has done in Iraq and Afghanistan has suited Iran very well. The US got rid of the Sunni Baath Party and Saddam himself in Iraq so that the Shia majority now get a vote. (Note shia muslims have mullahs... Iran is a Shia state). In Afghanistan the Taleban were the enemies of Iran because they were supported by Pakistan and Saudi Arabia (both sunni muslim states).
    You have removed from power in its two neighbouring countries two great enemies of Iran. Now they just want you to leave and they will be happy. If you bomb them watch the MANPADs and ATGMs flood over both borders. Denying the US air transport means travelling by road. Denying road and air transport suddenly makes both countries death traps for US forces and their allies. Need I go on about what will happen when the roads and the air are no longer safe?)

    The Cold War may be over but human conflicts continues. You are just upset that Russia is no longer as influential as when the Soviet empire existed.

    Actually the actions of Bush et al has made Russia rather more popular internationally than you seem to realise.

    Such as?

    But you are the radar expert. You know that radar invisibility does not exist and that in practical terms it means reduced detection range. Therefore a radar that can detect targets at 400km could still detect a stealth aircraft at 20km. This means all the radars need to be plotted and their effective range calculated with the detection rings plotted and flight paths routed around these rings. It is called mission planning.

    Spare me your crocodile tears for our morals and ideals. Try to remain in the technical realm.

    Of course, the west and the US in particular find it necessary to lecture the world on what is right and what is wrong but the signal is on transmit and not receive.

    We achieved this without the F-22. You are dreaming with your IR sensors.

    You have never taken on a decent air defence system, it was either poorly used (ie Iraq) or lacked the right tools for the job (Serbia).
    I might be dreaming about IR sensors yet the Russians continue to fit all their fighters with them and improve them. Mig-29, Mig-31, Su-27, Mig-35, Su-35, T-50... all have IRSTs fitted. All have IR guided BVR missiles too.

    Source please.

    A Stealth book by Keypublishing. Can't remember the title off hand.

    The reason why moving target indicator (MTI) radar works is because the target was not so rejected. In other words, BEFORE the MTI indicator is active for a target, the radar system ALREADY considered it a valid target and displayed its Doppler component.

    The An-2 almost has no stall speed and can actually fly backwards in a strong headwind. Its speed over the ground could be zero if it is flying into a 45km/h wind.

    You will be tracking a lot of cars before you start tracking An-2s.

    When you begin to exaggerate the PRAT-FALL's radar capabilities, you made radar detection a parallel issue.

    What prat fall radar? I am talking about the Tikhomirov NIIP AESA. If it is not for tracking targets the nose mounted X band AESA radar can't track then what do you suppose is its purpose? If you were designing for Sukhoi right now why would you incorporate an L band wing mounted AESA radar?

    We knew of this from the F-117 days. But the problem with the HF bands is array dimensions, as in meters wide. Sorry...But the wing leading edge does not qualify because the word 'wide' here mean both width and height.

    They have plenty of those sorts of radar on the ground, they don't need that in their aircraft.

    No...The Soviets did not.

    You use a past tense. Great way to discuss things. I can claim the US has no lead in stealth design at all... because I mean 3,000 years ago when the US didn't exist.

    Then do explain why now everyone, from the Russian to the Chinese, are jumping on this 'stealth' bandwagon. Your desperation is hilarious.

    Because when the other side has a technology it makes sense to both develop that technology for yourself and to devise ways to defeat that technology. And From the Russians to the Chinese they are doing both.

    Your attempt to distinguish the US from NATO regarding the F-117 made NATO irrelevant. The F-117 was an American product, flown by American pilots.

    NATO was irrelevant in Kosovo. F-117s were irrelevant in Kosovo. You can use air power all you want but without ground forces it only goes so far. Thought you learned that from Iraq?

    Hmmm, I ask you a question... "And how many SAM sites were destroyed by these Wild Weasels that are designed to defeat SAM sites?" and you reply:
    The fact that Zoltan Dani managed to launch several missiles meant that Wild Weasels missions were not %100 successful. This is funny. First you want to give Dani exaggerated technical credits, now you are trying to make it as if the Serbian air defense were completely helpless. Make up your mind.

    The 'spray-and-pray' tactic is tried and true.

    Never heard of suppressive fire? You can't apply spray and pray tactics with guided SAMs. They are either guided or they are not.

    Same for air defense missile training where multiple launches are advised even for a single hostile.

    That is an application of the mathematics of probability. Improving the probability of a kill by increasing the number of missiles fired. The problem is that with a guided missile that has no lock the probability is zero so launching more missiles does not change the kill probability.

    Yup...Just two out of tens of thousands of sorties. Not an air defense combat record to boast about. Not even for 'spray-and-pray' tactic.

    The purpose of any air defence network is to survive first and foremost, and secondly to survive to continue to make the task of enemy air power difficult.
    After what... 74 days of complete air supremacy (without F-22s) they took out 13 tanks and a few other items that wouldn't even cover the cost of one F-117.
    And lets be clear this was a superpower and her cronies pretty much operating from home soil with all their latest and greatest for OVER A MONTH!
    And at the end of that period the Serbia air defence force was as much a threat as it was on day one. NATO was beaten. They knew it.

    But the issue here is result and two out of tens of thousands sorties is a sorry result.

    The sad fact is that if NATO hadn't intervened Kosovo would never have declared independence, and Russia would not have opened its borders to South Ossetia and Abkhazia and Georgia likely would not have invaded leading to Russia recognising the independance of both regions. Still it showed NATO as being a largely paper tiger because of its internal divisions and its committee management would make it vulnerable in a situation where it found it self up against an enemy that actually was properly equipped and half as well motivated and trained as the Serbs were.

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    Re: PAK FA, T-50: News

    Post  nightcrawler on Wed Sep 22, 2010 1:28 pm

    @GarryB
    Of course, the west and the US in particular find it necessary to lecture the world on what is right and what is wrong but the signal is on transmit and not receive.

    lol! lol! lol!

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    Re: PAK FA, T-50: News

    Post  GarryB on Thu Sep 23, 2010 3:58 am

    It is one of the most annoying things that the US will berate places like China for their political prisoners, yet a US military base in Cuba contains their own little collection of political prisoners.
    The hypocrisy is hilarious.
    My favourite is when they call Hugo Chavez a dictator, I guess he is one of those special types of dictators that keeps on getting re-elected despite what underhanded tactics the CIA try.
    My other favourite is US claims of Russian excessive force in Georgia, but US imposed regime change in how many countries was justified?
    Russian forces securing military equipment left lying around by retreating Georgian forces is excessive force, but US bombing of civilian TV stations in Serbia is all part of war.
    It seems the western public are enthralled by the western propaganda machine to the point where they stop thinking for themselves and just believe what their TV tells them.

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    Re: PAK FA, T-50: News

    Post  Aegean on Thu Sep 23, 2010 7:44 pm

    GarryB wrote:It is one of the most annoying things that the US will berate places like China for their political prisoners, yet a US military base in Cuba contains their own little collection of political prisoners.
    The hypocrisy is hilarious.
    My favourite is when they call Hugo Chavez a dictator, I guess he is one of those special types of dictators that keeps on getting re-elected despite what underhanded tactics the CIA try.
    My other favourite is US claims of Russian excessive force in Georgia, but US imposed regime change in how many countries was justified?
    Russian forces securing military equipment left lying around by retreating Georgian forces is excessive force, but US bombing of civilian TV stations in Serbia is all part of war.
    It seems the western public are enthralled by the western propaganda machine to the point where they stop thinking for themselves and just believe what their TV tells them.

    Hey, that thing never ceased to amaze me too. But don't be so harsh, not all western people believe US propaganda.
    What is however worthy of discussion is why do the US need propaganda ?

    Why would they need to propagate a lie say for Iraq when everybody knows the war was for oil.
    Why did they need propaganda in Serbia when everybody knows that all they wanted to do was break up a country and create a larger area of US influence where before there was none. (I didn't see them leading a NATO force in Sierra leone, Rwanda or anywhere else people are being butchered in their 100's of thousands, yet they cared about a few thousand muslims. No offense to the muslims.. every human life is priceless, I am just stating a fact)

    Why do they need to find some excuse when they impose a dictator somewhere when everybody knows it is to create a puppet nation.

    What exactly is Guantanamo prison.. if not a blund violation of human rights ?

    How can the US decide which side is right and which side is wrong simply judging by their own ever changing interests in every dispute around the world?

    It seems lessons from Rome where not learned....


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    Re: PAK FA, T-50: News

    Post  GarryB on Fri Sep 24, 2010 4:39 am

    I have re read what I posted and it seems to me to be a bit of a rant.
    You are quite right Aegean I should really specify that I mean the problem lies with western politicans and governments... which is double irony really because they are responsible for the vast majority of harm to the world... which is no great surprise because they are and have been the global powers.
    Russia and the Soviet Union have interfered and supplied arms but have nothing like the history that countries like the UK, Spain, even Belgium and the Netherlands have.
    Look throughout the Americas and you will see native people are a second class people in their own country from Canada down to Argentina. The descendants of the conquering people are the ones with power and money and control and if the natives try to take back their country like Cuba and Vietnam and now Venezuela it is communism. It became communism for Cuba and Vietnam when the colonial powers led by the US resisted and the only support they could count on was from communist Soviet Union, or with Venezuela democratic Russia.

    I laugh at western countries claiming that Russia is still not a full democracy because there isn't enough variety of choice for the voter. The democratic governments in the west have gone through periods recently where the in power leader stayed in power because there was no alternative. George W Bush, Tony Blair, that Australian leader, Helen Clarke in NZ. They all stayed in power an extra election despite being not hugely popular ONLY because the alternative was worse.
    In the US there is the Republicans and the Democrats and pretty much nothing else, so you get two choices there.

    I would be much happier if the western governments practised what they preached and kept their opinions to themselves.

    How can the US decide which side is right and which side is wrong simply judging by their own ever changing interests in every dispute around the world?

    That is the key!
    They don't base their policy on morals or ideals. They base it on interests. Their own interests and no one elses.

    When Saddam invaded Iran he was a hero, because Iranian oil was out of western control. When he found himself short of money after that war with Iran he invaded Kuwaite and then he was the devil himself. The difference? By invading Iran he was securing more oil for western control. By invading Kuwaite he getting control of oil the West already have complete access to so the risk was that if he also invaded Saudi Arabia he might gain too much control of oil in the region and he might start demanding high prices for oil. The Risk was a monopoly on oil that already belonged to the west.
    If there was no oil pipeline from the Caspian Sea through Georgia no US president would be able to find Georgia on a map. The oil pipeline that bypasses Iran and Russia makes Georgia Americas best friend in the region.
    It all makes sense but it doesn't make America look very good, so we have to invent enemies like Venezuela and Iran and Russia.

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    Re: PAK FA, T-50: News

    Post  Austin on Tue Oct 12, 2010 12:13 pm

    Some PAK-FA stuff ( via black venom )

    Military tv program "CMOTP" broadcasted on Russian TV brings in 26:00 minutes the story of T-50 and previously unpublished interviews with pilot Sergei Bogdan and M. Pogosjan during Putin's visit to Zhukovsky, on16 June this year. Also there are some new cadres from 16th flight of T-50.

    Link for download:PAK-FA:Putin's visit to Zhukovsky

    Translated in English ( via black venom )

    Brisk running start and the plane is taking off from the airport Zhukovsky runway. Seconds later, very active pilotage and confident flight of this beautiful fighter. It's only the 16th flight of the totally new, 5th gen. Sukhoi fighter known as PAK-FA. She was designed to be VLO against opponents radars. The 16th flight she performed extraordinary, it looked as an airmeeting flight of a mature plane, depsite the fact she is a first prototype and her 16th flight. The plane was piloted 4mins before tochdown.

    History

    PAK FA's maiden flight performed 29-jan-2010 in far east Komsomolsk na Amure. After 6 succesfull flights, plane has been airlifted by An-124 Ruslan to LII Gromov, Zhukovsky airport where primary phase of flight testing has been started. Some history bublings about first idea of 5gen planes in 1970-es, then appearance of Mig 1.44, Su-47 berkut and how
    Sukhoi stepped from back and won tender for creation of 5 gen fighter.

    Statement of V. Putin about PAK FA program:
    2002 started program PAK FA,
    2004 he had seem the mock of PAK FA,
    2005 started finansing from state budget,
    on May 2009 he was the first one who saw the machine in assembling and today (17 june 2010)she flies).

    Then he made statement that PAK FA would be better in terms of flight autonomy, weapon systems and aneumverability.

    Timing for entering in service is very short, but attainable. On first two testbed there will be no onboard electronic equipment,like radars and AEW systems, weapons systems. It is planned for 3rd and 4th testbeds. First two testbeds was built to test aerodynamics, airframe and layout of aircraft. After completion of primary phase of flight testing it was concluded not to change airframe and layout of aircraft which significantly speed ups work completion.

    The very first look of PAK FA reveals some her genuine features - great maneuverability thanks to all movable tail fins and stabilisers. The motor gondolas are greatly distanced giving the plane better chances to survive direct hit or advent of fire.

    On plane are installed izdelie 117 engines. Its a temporary solution because more powerful and more sophisticated engines are planned. Engine and airframe are planes hearth.


    Pogosjan
    works on 2nd phase engines for pakfa will start in 1st quoter 2011.
    Engine nozzles will probably be flat to lower RCS. It is clear from airframe layout that PAK FA is developed to be LO plane. Also she can super cruise and attack targets in air and on ground (also at sea).

    Sergei Bogdan
    - The plane are very comfortable and easy to fly. She performed very well, and such stability, control and level of flight were not affordable for earlier tested planes. The plane can already be pilotaged in low level heights, analyze data obtained from such flights to assess planes maneuverability, stability and control.

    Next step is to evaluate performance of maneuverability, stability and control in regimes of greater altitude range flights, greater velocity and AoA ranges, greater g overloads in maneuvers. Radical changes in FBW software compared to legacy russian planes, great area of controlled aerodinamical surfaces, TVC, ensures extraordinary possibilities in dogfight.

    Pogosjan - The main characteristics of 5 gem fighter are not wider range of aircraft pilotage capabilities or maneuverability (which usually PAK FA does better than compared to all aircraft, series Su-30) It is a small radar reflection, which allows you to defeat the enemy at maximum greater distances (he emphasized importance of BVR combat capabilities of PAK FA). It should tbe provided by means of powerful AEW systems onboard, a powerful optical tracking system that allows him to engage targets in the IR spectrum, and other systems as well as and long range missiles that are being developed for the aircraft. Plane needs to be easily maintained and easily repaired on field.

    Maintenance cost must be significantly lower compared to legacy machines costs. In PAK FA are incorporated auto diagnostic systems with a function to signa malfunction of onboard systems and prevent greater failures.

    The share of composite materials in airframe are 33%. Number of parts reduced 4 times, compared to Su-27. In 2011 3rd and 4th testbeds will join flight testing, equipped with full onboard electronic and weapon systems.
    The effectiveness of PAKFA is on level like 3-4 legacy 4, 4+ gen fighters. The levels of RCS on PAK FA yet to be tested and verified in future testbed testings.

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    Re: PAK FA, T-50: News

    Post  GarryB on Wed Oct 13, 2010 1:15 am

    Nice stuff Austin... and thanks for getting us back on topic... apologies from me for that. Embarassed

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    Re: PAK FA, T-50: News

    Post  coolieno99 on Sat Oct 16, 2010 7:56 am

    video on PAK-FA


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    Re: PAK FA, T-50: News

    Post  Austin on Sat Oct 16, 2010 8:09 am

    Some details of 'NPP Motor's' development & participation in the PAK-FA Stage 2 engine: ( via Otaku )

    В кооперации с предприятиями «Объединенной двигателестроительной корпорации» (ОДК) НПП “Мотор” участвует в создании семейства перспективных двигателей с тягой 9-18 тонн для гражданской авиации и двигателя нового поколения для ПАК ФА II этапа.

    НПП “Мотор” участвует в создании научно-технического задела с применением ключевых технологий по следующим направлениям: разработка композитного входного направляющего аппарата и колеса первой ступени компрессора низкого давления с облегченной (полой) рабочей лопаткой на базе технологий диффузионной сварки и линейной сварки трением; разработка одноступенчатой турбины низкого давления с высокой газодинамической эффективностью и удельной мощностью; разработка высокоэффективного малоступенчатого компрессора высокого давления; разработка высокоэффективной форсажной камеры сгорания; разработка высокоэффективной малоступенчатой турбины низкого давления с рабочими лопатками из интерметаллида титана.


    In co-operation with the enterprises of the 'Joint Engine Corporation' (ODK), NPP 'Motor' will develop a family of future engines with thrust ranging from 9 to 18 tons- for both civil aviation and a new generation, 2nd Stage engine for the PAK-FA.

    'NPP Motor' is a participant in the development of scientific/technical solutions for the application of key technologies in the following areas:

    *development of a composite intake guide vane and turbines of the 1st stage low-pressure compressor with lightweight (hollow) fan blades based on diffusion and linear welding technologies.

    *development of a single-stage, low-pressure turbine with high gas-dynamic efficiency and power density.

    *development of a fewer-staged, highly efficient high-pressure compressor

    *development of a highly efficient combustion chamber

    *development of a highly efficient, fewer staged, low-pressure turbines composed of fan blades made with composites/alloys of titanium.

    http://www.bashinform.ru/news/304403/

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    Re: PAK FA, T-50: News

    Post  GarryB on Sat Oct 16, 2010 9:08 am

    The standard weapon pylon used for the R-77 has a built in ram arm that throws the missile down.
    The R-77 was designed from the outset to be an internal missile with the tail surfaces folded to allow it to fit in very small areas.
    In the early 1990s the Russians released drawings of single missile weapons bays for R-77 missiles that could be located on the back of an aircraft with doors that open for release to throw the missile up for it to light up and launch clear of the aircraft.
    I read recently that this concept of internal bays for weapons in unconventional places like over the top of the aircraft was finally dropped for logistic reasons because on the airfield it would be too hard to load and unload weapons from such positions without lots of extra ground equipment.

    BTW nice posts Austin.

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    Re: PAK FA, T-50: News

    Post  Corrosion on Wed Oct 20, 2010 4:57 pm

    Will Pak-Fa use tapes to cover rivets etc. as is done with American 5th gen. New taping will be required if a panel is removed for some reason and then fitted again followed by Ram paint. I think it will be essential to maintain steath. I think this is one of the main reasons F22 has such high maintainence costs.

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    Re: PAK FA, T-50: News

    Post  GarryB on Thu Oct 21, 2010 1:00 am

    Still pretty unknown really.

    The current models seem to be largely to test flight characteristics and flight controls etc. I know they started systems integration and radar testing on a Su-30M quite some time ago but that sort of stuff takes the longest so it is quite common to do that.
    A lot of the electronics and networking will have been developed and used on the Su-35S and there is talk of that aircraft entering production before the end of the year.
    I would expect the highest tech sensors will be kept for the T-50 however... we still have no idea what model IRST they will use, and of course online complaints about the rear end not looking very stealthy seem to be dealt with in the above posts kindly provided by Austin that show they intend to go with flat engine exhausts for stealth reasons.
    This shows they have some work to do on the rear end and what we see is not the final product.
    It also tells us they are interested in all round stealth and not just focusing on the front like the F-35.

    (Note flat engine exhausts lose a little power because of their shape but in return from a radar perspective they are better because their radar returns are spiky and so lower (and higher) from some angles whereas round exhausts have similar returns from a range of angles. From the IR perspective the shape forces the hot and cold air streams of the turbofan to mix more rapidly and reduce IR signature by a significant degree... all for the loss of something like 5% thrust from memory (There was a lot of talk about the exhaust of the F-117.)

    If they give it full 360 degree TVC there is still a possibility of losing the horizontal tail surfaces, which means reduced weight, reduced cost, reduced complication, reduced maintainence, and reduced RCS.


    Edit: BTW there is talk that they want to do about 2,000 flights to test systems and weapons and all sorts of stuff and that they are making 10 aircraft so they can get through these tests in a couple of years... instead of the 20 years it would take with one aircraft.
    The question is, will all those 10 aircraft be the same?
    For the most part I would assume for their results to be valid they would, but I also think that most aircraft will carry corner reflectors for safe navigation in normal airspace and only some aircraft will be used to test stealth capabilities.
    It will be interesting for them because they can test their ability to penetrate their own defences and their defences can practise against a real stealth target that will cooperate for a change... Smile

    Unless that Damn Clint Eastwood doesn't try to sneak into the one testing mind controls and fly it back to the USA... attack

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