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Saab Gripen : News And Discussions

Discussion in 'The Americas' started by Picard, Jun 1, 2012.

  1. Picard

    Picard Lt. Colonel RESEARCHER

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    And by either modern or 1960s figures, single engined fighters are not necessarily less safe than twin engined fighters. In fact, only design parameter that has major influence on safety by itself is aircraft's role: single-role fighters tend to be safer than multirole ones. You are focusing on the engine, but on modern aircraft there are many things that can go wrong and lead to loss of the aircrfat. Engine is only one factor.

    Clearly I do. Radar warns the enemy of your presence. Surprise is main factor in getting kills. Ergo, radar reduces ability to achieve kills.

    They also influence the way lift is created. Additionally, influence of canards (low-pressure zone on forward part of the wing) means that less control surafce deflection is required. Also:

    http://www.dtic.mil/dtic/tr/fulltext/u2/a245152.pdf
    "A small improvement in lift-to-drag ratio was noted at all tested angles above 10 degrees angle of attack."
    "The use of a canard placed above the wing caused a noticeable improvement in the lift-to-drag ratio for the tested angles of attack of 10, 16, and 19 degrees. The increase in the lift-to-drag ratio was 12 percent greater than the lift-to-drag ratio for the coplanar model."

    Notice the first sentence. "At all angles above 10 degrees angle of attack". 10 degrees is well below angle of attack that modern fighters need to achieve maximum lift (typically around 30*). However, first stall can happen considerably earlier (in that case, at 18 degrees AoA), which automatically means a major increase in drag. Canard provides reattaching mechanism which can, if canard is properly sized and positioned, prevent stall alltogether up to maximum lift AoA (which will be higher than that for wing alone). Ergo, lower angle of attack will be required for same amount of lift, which automatically means better lift-to-drag ratio.

    Take a look at this, from the same document:
    "The maximum CL at 10 degrees AOA was only 3.4% greater than the baseline value. At 22 degrees AOA, where the first stall occurred, the lift was greater than the baseline value by 34%. This dramatic increase in lift is thought to be due to the downwash of the close-coupled canard impinging upon the flowfield of the wing, thereby delaying the onset of flow separation. At 34 degrees AOA, the lift was 9.4% greater than the baseline value. At 40 degrees AOA, where the lift was previously maximized for the wing/body configuration, the lift was 7.2% greater than the baseline value. In general, the lift enhancement was not as great where major separation did not previously exist for angles of attack tested in the baseline configuration. At 48 degrees AOA, where the second stall occurred, the lift was greater than the baseline value by 18.3%"
    "At an AOA of 10 degrees, the CL/CD ratio was 34.5% less than the baseline value. The CL/CD ratios were 7.4%, 8.9%, 11.4%, and 10.4% greater than the baseline values at angles of attack of 22, 34, 40, and 48 degrees."

    So it is basically exactly as I have been saying. Long coupled canard-delta or basic tailless delta does have better lift-to-drag ratio in level flight, but close-coupled canard increases lift and improves lift/drag ratio when aircraft is turning. Maximum drag is larger for close coupled canard configuration, because maximum lift is also larger (massively so, in some cases). But for equal lift (and, all other things being equal, same turn rate), close coupled canard configuration will result in less drag due to improved lift-to-drag ratio for that angle of attack and due to requiring lower angle of attack for same amount of lift.

    Unstable canard-delta aircraft will also suffer a negligible drag penalty in level flight regardless - most of drag penalty in level flight with stable canard-delta aircraft is due to the large amount of lift required by the canard and thus high canard loading (lift-induced drag). But with modern unstable delta-canard designs, canard is unloaded in the level flight, meaning that only drag it produces is form/profile drag, assuming that it is not coplanar to wing in which case there is also interference drag to consider. On the other hand, it reduces trim drag at higher speeds due to smaller center of pressure lift, especially at supersonic speeds.

    That it is more complex than you think. All three parameters are important, but drag gets less so at high altitude. Typhoon's engines are specifically designed for high altitude operations whereas Gripen's RM-12 is basically an upgrade of F-414, which is not precisely a high altitude engine, so that is a factor too as Typhoon will likely loose less thrust with increasing altitude.

    Increase lift and improve lift/drag ratio for given AoA and speed. Which means less drag for same lift. So to fix your statement:
    "Ultimately engine power overcomes this."
    Drag reduction only happens in level flight, and only with stable designs or designs where canard is in the same plane as the wing.

    Due to reasons unrelated to number of engines.

    Unlike Typhoon, Gripen has well-developed aerodynamics, and better EW suite. So if Gripen is sh*t, then Typhoon is what? A rotten corpse?

    With reliability of identification being what? 30%? And no mention of range either.

    It would have. Germans overran French Army and British Expeditionary Force in 1940 despite being outnumbered and using inferior technology, Me-262s achieved at most a 1,5:1 kill:loss ratio against allied prop fighters, Pakistani F-86s achieved a favorable kill/loss ratio over Indian MiG-21s, MiG-15s and MiG-21s achieved a kill/loss ratio of 3:1 against F-4s early in the Vietnam war.

    Face it, competence>numbers>>>technology.
     
  2. Picard

    Picard Lt. Colonel RESEARCHER

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    Which is relevant how? There were twin-engined fighters which are as small or smaller than contemporary single-engined fighters (F-5, for exaple), and single-engined fighters that are larger than contemporary twin-engined fighters (F-35), but as a rule, single-engined fighters are smaller than twin-engined ones.
     
  3. BMD

    BMD Lt. Colonel ELITE MEMBER

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    Yes but not much smaller and they only have half the power.
     
  4. BMD

    BMD Lt. Colonel ELITE MEMBER

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    And it is always single-engined fighters that have more go wrong with them.

    Actually superior detection, targeting and positioning is what gets kills. There's no point standing in the middle of a field with a pistol looking for a scope glint on the mountains. Well done you've detected the enemy first but you have no way of aiming at them or getting to them before they pick you off. That's very much the case with Captor-E vs smaller radar, even if they use the same missile, it's the equivalent of using the same sniper rifle but with iron sights instead of a Schmidt & Bender 5-25x56 PM II LP telescopic sight. Using passive RWR targeting at 80km would be like trying to get a head shot at 800m with iron sights.

    Nope, you've posted this before. It's comparing CCC relative to a non-canard delta. So the results are irrelevant to this discussion.

    This study however shows that the designers of the Typhoon looked at the CCC design but rejected it due to inferior drag, reduced instability margins and only marginal improvements in lift.

    http://ftp.rta.nato.int/public//PubFulltext/RTO/MP/RTO-MP-035///MP-035-01.pdf

    Most of the drag penalty in steady level flight is down to surface area (Cd0) because the required lift is minimal, so the CCC, with massive canards is badly affected. You can reduce canard size but then you have to reduce instability margin and increase trim drag whilst reducing manoeuvrability.
     
  5. BMD

    BMD Lt. Colonel ELITE MEMBER

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    Drag at a given AoA and airspeed is less but air density tails off asymptotically and lower densities require higher AoAs for more lift. Rafale's engines were designed for high altitude and it does no better. But yes, the Typhoon's superior thrust at high altitudes and its contribution to turning and lift (due to AoA), as well as overcoming drag, will also help with high altitude manoeuvrability.

    No, LCC has reduced drag, and the Typhoon has a better TWR and far better high altitude performance as proven by its service ceiling.

    Maybe not, aircraft are complicated. Electrical power generation redundancy etc. Balanced thrust lift either side to prevent nasty oscillations. Lot of potential reasons why single-engined fighters are more crash prone? It's easier to make a pilot error with a pit bull than a German Shepherd.

    Oh? Says who? The Saab 'we've no customers' fan club?

    Another guess on your part. Reliability will be very good on a 1,500 T/R module GaN radar that's been in development for a decade.

    No they didn't.

    AIM-9 Sidewinder - Wikipedia, the free encyclopedia

    The first combat use of the Sidewinder was on September 24, 1958, with the air force of the Republic of China (Taiwan), during the Second Taiwan Strait Crisis. During that period of time, ROCAFNorth American F-86 Sabreswere routinely engaged in air battles with the People's Republic of China over the Taiwan Strait. The PRC MiG-17s had higher altitude ceiling performance and in similar fashion to Korean War encounters between the F-86 and earlier MiG-15, the PRC formations cruised above the ROC Sabres, immune to their .50 cal weaponry and only choosing battle when conditions favored them. In a highly secret effort, the United States provided a few dozen Sidewinders to ROC forces and an Aviation Ordnance Team from the U. S. Marine Corps to modify their Sabres to carry the Sidewinder. In the first encounter on 24 September 1958, the Sidewinders were used to ambush the MiG-17s as they flew past the Sabres thinking they were invulnerable to attack. The MiGs broke formation and descended to the altitude of the Sabres in swirling dogfights. This action marked the first successful use of air-to-air missiles in combat, the downed MiG's being their first casualties.[8]

    Depends on the competence difference. A 10% experience gap won't overcome a 20 year technology gap. You can't put an elite sniper with an iron sighted .22 up against a well-trained sniper with an L115A3 and Schmidt & Bender 5-25x56 PM II LP telescopic sight and expect him to win.
     
  6. Picard

    Picard Lt. Colonel RESEARCHER

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    Half the power is irrelevant as single-engined fighter will be lot lighter (not half the weight but more like ; F-15A weighted 12.975 kg empty while F-16A weighted 7.387 kg; so 57% of the empty weight at 50% of the thrust), plus have far better thrust/drag ratio.
    Single vs twin engined fighters | Indian Defence Forum

    Wrong. Twin engined fighters have two engines, and since Western twin-engined fighters tend to have insufficient separation, what affects one engine is likely to affect another. All other things are similar.

    Funny, considering that sniper rifles use *passive* targeting. And FYI, IRSTs range covers 100% of actual firing opportunities. Having a 150 km range missile is useless if it can't hit jack shit at that range.

    FYI, most successful sniper of the Winter War (and one of most successful snipers in history) used hunting rifle with iron sights.

    They are relevant because Typhoon's canard is too far forward to influence the wing.

    Drag difference is not that great for properly-designed close-coupled canard configuration, but Typhoon configuration had unfavorable interference between canards and ventral inlet.

    From your link:
    "a low forward foreplane position then results in the smallest foreplane area, with a consequent benefit on supersonic drag."

    Ergo, they sacrificed maneuvering performance for better cruise performance.

    As for improvements in lift, that may be true but only for pre-stall angles of attack. Close-coupled canard delays stall, long-arm one has no such effect.

    Wrong. In stable canard-delta configuration, canard has to be highly loaded and that is what causes poor lift/drag characteristics. But with unstable canard-delta configuration, canard is unloaded in level flight precisely because having a loaded canard would cause unacceptable drag penalty.

    And Typhoon doesn't have large instability margin anyway. It is half of what they originally intended.

    In level flight, and that is a minor reduction at best since size difference is not that large

    Funny, considering that thrust has nothing to do with oscillations. And Typhoon in Spain crashed shortly after takeoff due to oscillations of increasing amplitude followed by a violent pitch-up. 2 Gripens crashed due to pilot induced oscillations related to control surface servo rate limits.

    Eurofighter Typhoon got exports to Austria (15), Saudi Arabia (72) and Oman (12). Austria was won with bribes, Saudi Arabia was won with bribes and there is no word on Oman as yet, but I'll be surprised if bribes weren't involved. Saab Gripen got exports to South Africa (26) and Thailand (12), lease-and-buy to Hungary (14) and lease to Czech Republic (14). Quite good for a nation with little political clout.

    So you counter my examples by a completely unrelated example.

    Depends on conditions. In an open field on a sunny day no, but if there is some cover, then it comes down to skill.
     
  7. BMD

    BMD Lt. Colonel ELITE MEMBER

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    It won't be half as light because many things won't be halved, not least the pilot and cockpit.

    Does seem that way based on statistics. Single-engined fighters just love soil more.

    Nope on two counts. Many sniper rifles use laser range finders and laser IR scopes for night. Firing opportunities from outside 100km have been demonstrated. You are behind the times. Missiles are far more thoroughly developed these days. Meteor is already better than anything out there but they're continuing to develop and polish the product.

    There’s No Escaping MBDA’s Meteor Missile | Aviation International News

    GF2 was a tough test of the missile’s ability to snap-up through thick air in a tail chase.GF3 then tested high-altitude performance, GF4 was a longer snap-down tail chase against background clutter and GF5 was a high-speed head-on engagement at “well in excess of 100 kilometers,” said Bradford. The Meteor’s actual maximum range is classified.

    Finally, GF6 was another long-range and head-on engagement in March-April of this year that fully tested the missile’s data link to and from the launch aircraft. Bradford noted that the targets for all except GF5 were high-subsonic Mirach drones with a radar cross section “equivalent to a real-world fighter,” according to Bradford. GF5 engaged aBQM-167 drone.

    All the targets conducted a final evasive maneuver,” added Bradford. There have since been three more firings from the Tornados over the Aberporth range off the coast of Wales, to test the Meteor’s performance against countermeasures (chaff and jammers).


    Vasily Zaytsev did.
    Vasily Zaytsev - Wikipedia, the free encyclopedia

    Carlos Hatchcock did.
    Carlos Hathcock - Wikipedia, the free encyclopedia

    Craig Harrison did.
    Craig Harrison (sniper) - Wikipedia, the free encyclopedia

    Nope and definitely nope at the AoAs required for sustained turning.

    Yes, all Europe's engineers are idiots, even though they considered the CCC idea and rejected it after thorough examination.

    Not if you read on. The CCC adversely affects drag in most flight regimes for the same instability margin, simply because it has to be way bigger. Furthermore you further indicate your ignorance if you think supersonic drag is just about cruise, it's actually a big part of BVR combat manoeuvring.

    Post stall has no place in realistic air combat, nor do AoAs above 18deg much of the time. The energy sacrifice is too high.

    Nope. Lift-induced drag is negligible relative to Cd0 in level cruise but it becomes dominant in high g turns. I'm not going to waste my time showing the maths, I suggest you go read a book that discusses typical values of Cd0 and k and learn for yourself.

    It was reduced from the optimal 15% to 8% because 15% wasn't realistic in terms of the FCS. The designers thought it best not to have an aircraft that kept crashing, like Gripen.

    At all sustainable AoAs. The difference in canard span is huge relative to aircraft size, as I've shown many times before.

    Saab Gripen : News and Discussions | Page 22 | Indian Defence Forum


    Actually thrust lift can be a factor in balancing oscillation, as can a poorly thought out canard-wing-FCS combination that prevents things getting out of control.

    Meanwhile Gripen and Rafale can't even get deals with bribes.

    Your examples were just wrong, what can I say. I provided an example where technology provided a win. A could have used British infantry vs Zulus but seemed somewhat unfair. The Zulus were actually extremely competent and experienced fighters, as were the North American Indians but spears and arrows don't work very well against cannons and guns. Is running ant men with rifles a good tactic? It's a necessary tactic if you wish to fight people with guns without a gun, which is essentially what you wish to do.

    You can't rely on cover, and there are no bushes in the sky.
     
  8. Picard

    Picard Lt. Colonel RESEARCHER

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  9. Picard

    Picard Lt. Colonel RESEARCHER

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    No it won't, but difference will be minor. Few aircraft pairs where single engined fighter used same engine as twin engined one:
    F-16A vs F-15A: 57% empty weight with 50% thrust
    F-104 vs F-4E: 46% empty weight with 43%* thrust
    F-20 vs F-18: 57% empty weight with 48%* thrust

    And you are completely ignoring thrust-to-drag ratio which will be better for a single-engined fighter even if thrust-to-weight ratio is worse. F-16s F100-PW-229 has 129,7 kN of thrust and 88 cm inlet diameter (6.082 cm2 area), while F-18s F404-GE-402 has 78,7 kN of thrust and 79 cm inlet diameter (4.902 cm2 area). Thus, thrust-to-inlet area ratio would be 21,33 N/cm2 for the F-16 and 16,05 N/cm2 for the F-18. Both engines have same thrust-to-weight ratio and use similar technologies. For Gripen's RM12, ratio is 20,4 N/cm2 (80,5 kN, 3.944 cm2). Single engined fighters will also have lower wave drag.
    Single vs twin engined fighters | Indian Defence Forum

    *would have been 50% if it weren't for the fact that the F-4 and F-18 in examples use more advanced version of the engine

    Based on lies, you mean. Actual statistics show otherwise.
    Single vs twin engined fighters | Indian Defence Forum

    And Meteor Pk was less than 10% in these tests, I assume. At least if they did it properly.

    Yep and definetly yep.

    Two most experienced companies in that field, Dassault and SAAB, have considered the CCC idea and accepted it after thorough examination. Why? Different requirements, less optimization for cruise and more for maneuvering combat, and more experience in designing canard-delta aircraft.

    I'm not ignorant of reality, you are. Close coupled canard on a properly designed aircraft that was designed to have canards from beginning (on Typhoon they are, aerodynamically speaking, just bolted on) do reduce supersonic drag in turn.
    http://i29.photobucket.com/albums/c285/Scorpion82/EF technical/EurofighterStudies.jpg
    http://i146.photobucket.com/albums/r279/sampaix/198520EFAa.jpg

    Reason that close coupled canard adversely affects drag in the design discussed is because it is incompatible with ventral inlet that was used in Typhoon.

    Take a look here:
    http://www.targetlock.org.uk/typhoon/eap.jpg
    Close-coupled delta.

    Close coupled canard reduces drag for the same amount of lift even at low AoA, it is just that it does not offer major increase in lift as it does at high AoA, and may slightly reduce lift if canard is not properly positioned vertically.

    http://www.dtic.mil/dtic/tr/fulltext/u2/a245152.pdf
    "It was found that a properlylocated canard enhanced the lift at all tested angles of attack, compared to the baseline wing/body configuration results. The lift enhancement was maximized in the post-stall regimes, reaching values up to 34%. A small improvement in lift-to-drag ratio was noted at all tested angles above 10 degrees angle of attack."
    "The use of a canard placed above the wing caused a noticeable improvement in the lift-to-drag ratio for the tested angles of attack of 10, 16, and 19 degrees. The increase in the lift-to-drag ratio was 12 percent greater than the lift-to-drag ratio for the coplanar model."
    "The increase in maximum CL was due to constructive interference between the vortex systems of the wing and canard. It is thought that constructive interference occurs when the downwash from the canard suppresses the flow separation on the wing. The formation of wing leading-edge vortices are delayed until induced downwash of the canard supports flow separation. The longer the flow separation is delayed, the greater the lift enhancement. "
    "Er-El and Seginer found that a close-coupled canard placed upstream and above a 60-degree swept wing delayed the onset of wing-leading-edge vortex breakdown for an angle-of-attack range from 14 to 24 degrees."
    "If the canard was mounted too far forward, the canard/wing combination would actually generate less lift than what the wing and canard could generate separately. (It should be noted that the long-coupled canard on the X-31 is a control, and not a lifting, device.) "
    "Lacey postulated that the canard downwash delayed the leading-edge stall of the wing in a manner similar to that of a leading-edge slot. The canard could be thought of as a large low-drag boundary-layer device. "
    "Beyond an 18 degree angle of attack, the wash of the canard impinged upon the wing in a downward direction, and thereby delayed the onset of flow separation on the wing and correspondingly increased the lift. "

    And yes, high angles of attack do have place in some situations even in many-on-many combat, but only assuming that they increase turn rate over what it was, and that aircraft can regain energy (which is the actual reason Gripen needs more thrust). Turn rate is highest at maximum AoA achievable before stall, and close coupled canard delays stall.

    There is a reason why AoA limits are between 25 and 30 degrees (25 deg Typhoon, 25,52 deg F-16, 26 deg Gripen, 29 deg Rafale) instead of 18 degrees. Reason being that there are situations where you want to exchange energy for position.

    As for post-stall, no it does not have place in air combat, but ability to achieve post-stall flight improves safety while not sacrificing performance.

    MACH Aviation Magazine - på webben
    "In the high AOA and spin tests that has taken place since 1996 and recently concluded successfully, the normal tactic was to initiate the tests with a near vertical climb with speed dropping off to near zero and a rapid increase of AOA up to extreme angles, and the aircraft could then be “parked” at 70 to 80 degrees of alpha. When giving adverse aileron input there, a flat spin with up to a maximum of 90 degrees per second of yaw rotation started and could then be stopped by pro aileron input. Recovery followed, whenever commanded."
     
    Last edited: Aug 12, 2014
  10. Picard

    Picard Lt. Colonel RESEARCHER

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    I have read more documents about canard-wing aerodynamics that you even know exist. And yes, lift induced drag is dominant in turns, and only reason close coupled canard does drag more than long arm one is because it produces more lift. More lift means higher instantaneous turn rate, and pilots have often sacrificed sustained performance for higher acceleration or instantaneous turn rate.

    And instead opted for an aircraft that will keep getting shot down if it comes to a war.

    And it has very little to do with drag. How canard and wing interact is far more important than canard span by itself.

    And as a matter of fact, you can think of canard as a small wing. Higher-span wings drag less at high angles of attack than lower-span ones, which is the reason why fighter aircraft do not have wing sweep angles of 65* or 70*, but instead minimum possible required by their performance goals.

    Thrust does not produce lift until aircraft starts pitching up, and you obviosuly don't know what pilot induced oscillation is:
    "The captain's large and rapid elevator control reversals, which resulted in an increasing divergence above and below the target pitch attitude, were consistent with a "classic" pilot-induced oscillation (PIO). Essentially, the captain made each increasingly larger elevator input in an attempt to compensate for the input he had made in the opposite direction about 1 second earlier. PIO in the pitch axis can occur when pilots make large, rapid control inputs in an attempt to quickly achieve desired pitch attitude changes. The airplane reacts to each large pitch control input, but by the time the pilot recognizes this and removes the input, it is too late to avoid an overshoot of the pilot's pitch target. This, in turn, signals the pilot to reverse and enlarge the control input, and a PIO with increasing divergence may result.iii "
    "The short period is normally a fairly fast cycle, where the pilot will see the aircraft pitch changing to correct itself as soon as what ever caused the deviation is removed. If the cycle is a bit slow, the pilot is apt to intervene to correct the pitch to the desired attitude. A problem could occur if the pilot does this just as the natural stability is restoring the aircraft attitude on its own. The combination of the aircraft pitching on its own coupled with the pilots input can lead to a very fast "correction" and a resulting "overshoot" of the desired attitude, with a repeat of the process in the reverse direction. The result is an oscillation, with the pilot's attempts to arrest the pitch changes actually contributing to them. A PIO occurs when a pilots inputs combine with the natural frequency of the aircraft's motion such that the pilot inputs sustain and/or perhaps even increase the amplitude of the motion. A PIO can occur in any axis, although pilots are most familiar with oscillation in pitch and roll. "
    "The oscillation frequency itself is influenced by several factors, including (but not limited to): • The basic stability of the aircraft (more stable, faster rate). • The amount of damping in the design, (the larger the horizontal stabilizer and/or the more moment arm, the more damping, (think of a paddle at the end of a broomstick, the longer the handle or the larger the paddle the more it wants to align with the wind). • Moment of Inertia, (the amount of mass that is forward or aft of the wings (or, in the case of roll, way from the longitudinal axis), which means more inertia for the natural stability to counter once the oscillation starts - more moment of inertia nets a slower rate). • The altitude (high altitude thinner air damps less so slower rate). • Advanced flight control inputs, (Fly-By-Wire (FBW), Stability Augmentation Systems (SAS)."

    In short, more maneuverable aircraft is, more vulnerable to pilot induced oscillations it is, regardless of thrust. It also means that larger aircraft are automatically less vulnerable to pilot induced oscillations due to inherent inferior maneuveraility / responsiveness.

    Gripen exports:
    South Africa (definite involvement of bribes: Saab admits R24-million bribe paid to clinch arms deal | News | National | Mail & Guardian
    Thailand
    United Kingdom (funny how Empire Test Pilots' School did not consider single-engined Gripens to be "unsafe")
    Hungary (lease-and-buy, possible involvement of bribes: Sweden extends Saab bribery probe to Hungary| Reuters

    Typhoon exports:
    Austria (possible involvement of bribes: New Allegations Haunt EADS Fighter Jet Deal - SPIEGEL ONLINE , http://www.nytimes.com/2012/11/08/b...ffices-raided-in-corruption-inquiry.html?_r=0)
    Saudi Arabia (definite involvement of bribes)
    Oman

    So 2 out of 4 (or 1 out of 3, depending on how you count) Gripen exports were helped with bribes, compared to 2 out of 3 Typhoon exports.

    And fighters are not people, and missiles are not bullets.

    Besides, you are incorrect. You can *create* bushes in the sky, chaff if the enemy is using radar, or flares if the enemy is using IRST. Clouds aren't impenetrable for either radar or IRST, but can degrade detection range.
     
    Last edited: Aug 12, 2014
  11. Picard

    Picard Lt. Colonel RESEARCHER

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  12. BMD

    BMD Lt. Colonel ELITE MEMBER

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    An unnecessary degradation.

    Drag is largely proportional to area. Weight is largely proportional to volume. The weight does not double, therefore volume does not double, therefore the increase in a squared dimension is less still.

    No, just based on simple statistics. The majority of single engined aircraft have proved more unlucky for their pilots.

    They did it as properly as any test could be done, and Pk was far higher than 10%. The only issues that arose were to do with design errors, which have since been fixed. It's when you find no issues during development and testing that you should worry because it means you've missed something.

    There’s No Escaping MBDA’s Meteor Missile | Aviation International News

    "MBDA admitted to setbacks in the test program. A total of 21 firings were required to achieve the 16 successful ones described above. For instance, just one incorrect line of new software code defeated the first attempt to demonstrate GF3, by causing the location data transmitted from the aircraft to the missile to be misinterpreted. GF4 had to be re-flown after a telemetry problem, and so did GF6 after a connector/cable problem prevented the motor from igniting. “There were no short cuts in this development, we had six nations watching us all the time,” Bradford noted. The last three firings on the Aberporth range were all first-time successes and direct hits, he added.

    Operational analysis conducted by the company suggests that a fighter firing the Meteor is six to eight times more likely to survive an air-to-air engagement against a representative threat than one equipped with a currently available medium-range AAM. However, it remains to be seen whether the European governments that sponsored the development will be willing to share Meteor’s advanced technology with many other countries."

    Nope. You vastly overestimate the AoAs required for sustained turning.

    More like omnirole aircraft and lack of cash to work on a fully optimised air superiority design.

    Every post you make proves your ignorance, like failing to recognise the relevance of supersonic turns in BVR combat, climb rate and missile kinematics. CCC was considered and rejected because, overall, it was an inferior solution for air superiority:

    http://ftp.rta.nato.int/public//PubFulltext/RTO/MP/RTO-MP-035///MP-035-01.pdf

    The fuselage intake was chosen for maximised engine performance. Rafale and Gripen chose side inlets so they could have stronger pylons on the body. The decision, along with CCC, reduces thrust at higher AoA and high altitude, as well as increasing RCS and drag, which can clearly be seen by comparing frontal cross sections. The only advantage is extra lift and smaller turning circle at lower altitudes.

    False, your study compares only against a standard wing.

    http://ftp.rta.nato.int/public//PubFulltext/RTO/MP/RTO-MP-035///MP-035-01.pdf

    "
    A low forward foreplane position then results in
    the smallest foreplane area, with a consequent benefit on
    supersonic drag.

    Further, at the level of instability chosen for the aircraft,
    there was little effect on maximum lift of either position,
    whilst for a less unstable aircraft. a high aft foreplane
    does provide some benefit on lift. Further, the low
    forward foreplane is more effective as a control surface,
    with consequent benefit for nosewheel lift, trim and
    manoeuvre capability. This increase in effectiveness is
    maintained, even at high angle of attack "
     
  13. BMD

    BMD Lt. Colonel ELITE MEMBER

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    We heard your pogo-induced rantings about a range of subjects, from stealth to radar, all equally absurd as the ones preceding them.
    Higher ITR for shorter periods with more energy loss. A Typhoon can maintain ITR for longer, and repeat more frequently. It also regains energy in between ITRs faster due to the thrust vs drag issue.

    Meteor + Captor-E = You'll never even get close enough to try. Based on AIM-120C-5 range at 30,000-35,000ft (10-11km) and Captor-E performance, it's even doubtful that an F-35 would get the first shot against a Captor-E equipped Typhoon with Meteor:

    F-35: a game changer in modern warfare

    "
    According to a calculation by a senior EADS radar expert, the Captor-E... is capable of recognizing the F-35 at around 59 kilometers away. "
    [​IMG]

    Canard span is very important wrt drag, as are the two side intakes for just one engine.

    Another incorrect statement. LERX... Missiles... think man think. The canard doesn't actually provide lift directly in a subsonic turn but it increases wing lift.

    Still seems like the aircraft gets itself in a lot of trouble one way of the other. More pilots fly the Typhoon more often, yet with less pilot-induced crashed. Safer design.

    All old Gripen C sales. Nothing for Gripen NG.

    Whatever. Only the Tornado sale to Saudi Arabia was widely been acknowledged as a fraud.

    They're the target nonetheless. Missiles are able to self-counter wind, the Earth's rotation and gravity within their range limits. All that has to be calculated for a bullet.

    Chaff only has a chance of working if we're talking about expandable DRFM chaff. And guess what? Meteor has been tested against that. Why do you think we spend nearly a decade testing? These are not some 1950s tests against large non-manoeuvring targets with ECM. These tests are against cruise missile sized RCS targets, that manoeuvre and use ECM.
     
  14. Picard

    Picard Lt. Colonel RESEARCHER

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    Only if you forget corresponding improvement in other parameters.

    As I said, engine face drag is a major source of drag, along with form drag. Single engined fighters have advantage in both.

    How does the F-15 and F-16 comparision suddenly translate into a "majority of single engined aircraft"? I have already shown that engine is not the leading cause of aircraft loss, and that many single-engined fighters have proven safer than twin-engined counterparts.

    They gave similar bombastic predictions for BVRAAMs before the Vietnam war, so I'd advise you to stop quoting sales brochures.

    Instantaneous turns require higher AoA than sustained ones, and are far more important. And Typhoon's canard does not influence wing at ANY AoA as its vortexes break down too early, as there is nothing to reinforce them early on (no wing, no wing vortexes), unlike with Gripen and Rafale.

    Typhoon was originally to have close coupled canards too:
    http://i146.photobucket.com/albums/r279/sampaix/198520EFAa.jpg
    British proposal for it also had close-coupled canards:
    http://i307.photobucket.com/albums/nn308/Kypchakturk/1980P110a.jpg

    Only reason why it ended up with a long arm canard was that close-coupled canard produced too much supersonic drag when combined with chin intake, so they used an inferior Herbst concept which was designed with thrust vectoring in mind.

    Inferior choice with the design they chose, not inferior choice overall. Close coupled canard does, in fact, improve supersonic maneuverability and is overall a superior solution for air superiority aircraft.

    And because side inlets actually work with canard positioning that was chosen.

    Actually, it improves sideslip and high AoA performance, reduces the possibility of both air intakes being affected by possible adverse air flow phenomena and improves structural strength (especially in case of Rafale). Plus they don't really increase frontal area.

    Long arm canard has no influence on the wing beyond the increase in wing area it provides.

    Funny that actual pilots have always preferred energy loss to steady state turn. Reason? If you pull the steady state turn, enemy is quite likely to get on your six o'clock and blow you out of the sky, and you will rarely to never know where all the enemies are. To counter it, you need better transient performance, which is exactly what close coupled canard provides.

    Yeah, just like MiG-19&21 never got close enough to the F-4s... oh well.

    Not compared to what I listed. And by the way, you know what span loading is? Wings with larger span actually drag less at high AoA.

    Unlike you, I do think.
    1) Typhoon's canard is far too forward to increase wing lift, it is simply a control device
    2) canard does not provide lift during level flight. But during pitch-up, vortices shed from its leading edge will cause it to produce lift, if only for a relatively short time.

    And that has nothing to do with canard position, or number of engines. Besides, you want pilots to fly Boeing 707 instead of air superiority fighters? I believe that it is quite safe design.

    Gripen NG isn't even in production yet, babblemouth.
     
  15. BMD

    BMD Lt. Colonel ELITE MEMBER

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    Nope, I've included them all I believe.

    Actually it isn't a major source and is compensated for by having twice the power. Intakes where the air is being decelerated in a source of drag and Gripen still has 2 of those.

    I could include MiG-21s and F-104s too.

    Except they weren't well designed, extensively developed and rigorously tested against counters.

    By having less drag and more thrust a Typhoon can sustain ITRs for longer and repeat more often. TVC provides the best ITR but totally wastes energy in doing so.

    Hah, do you never try to draw any logical conclusions from the fact that all these designs were considered and dropped? The twin-fin tail was also considered and dropped. You show that all these concepts were thoroughly considered by people far cleverer than you'll ever be and then dropped. Then you make massive assumptions and far reaching, but unfounded unipolar statements as to why they were dropped. Larger canards are required even for lower instability with CCC, that increases drag at any speed and adversely affects manoeuvrability. Chin mounted intakes just offer superior performance at higher AoAs and less drag by not interfering with the wings.

    Yeah, no it doesn't. The large canards increase drag, sapping the platforms energy, making sustaining turns far harder, and because of the reduced subsonic instability with CCC, they also suffer increased supersonic stability, increasing reluctance to turn. It's a really crappy solution for air superiority aircraft and J-20 designers agree (Asians not known for their low IQs).

    The canard position was chosen by the inlets because you can't mount the canards directly in front of the inlets now can you? So LCC was automatically ruled out.

    During side-slip one intake is partially cut off front airflow by the aircraft's beak. Also applicable with cross-winds - see landing problems, oscillations etc.:troll:



    Yeah, I bet it doesn't even produce vortices at all, or affect airflow directly in front of the wing.:facepalm:

    Oddly that's exactly why you don't sacrifice too much energy, like all noobs with TVC do. You don't know where all the enemies, sacrifice energy to evade on fighter, and his wing man might get on your six. The slower you go, the less time it takes any missile to reach you, and the less it has to turn.

    Mostly they didn't fair too well. Even the crappy AIM-7D/E missile scored 60 kills. Only F-15 ever shot down was shot down BVR by a MiG-25PD with an R-40.

    R-40 (missile) - Wikipedia, the free encyclopedia

    Which is presumably why all fighter aircraft look like U-2s. The canard is not providing lift itself at high AoA, it is countering the lifting moment.

    In your opinion.

    Rubbish.

    Correct, after that it counters pitching moment more effectively than CCC allowing for greatly instability and allowing the aircraft to turn with less input force, whilst increasing wing lift at all AoAs pertinent to STR.

    Might be intake choice. Either way, it sure does crash a lot.

    Bit of a waste of time then really. By the time it's really, people will have moved on and be talking about Taranis and nEUROn. Maybe we should given up on those and produce a Tornado NG with a few minor cosmetic tweaks and upgraded avionics and try sell that. Perhaps cut costs by having just one engine.
     

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