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Close coupled vs long arm canard

Discussion in 'The Americas' started by Picard, Aug 23, 2014.

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  1. BMD

    BMD Colonel ELITE MEMBER

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    :facepalm: But vastly more combined intellectual resource than your protagonists.

    You fail to understand again, I'm talking about the lower lip.

    [​IMG]

    I'm talking about engine performance at high AoA, not simply being able to achieve high AoA. By improving thrust, you increase the combined force in the turn direction.

    No they don't. They're LERX mounted, which could easily have been done on a Typhoon.

    Closer coupled but still way longer than Rafale or Gripen. The Chinese who further developed the design increased the separation further.

    As you have incorrectly explained amidst horseshit about STR being higher at 15,000ft than sea level, proving that you're not worth listening to about anything, since you got a complete basic wrong and therefore can't possibly understand more advanced aerodynamic concepts, since you don't even understand lift.

    LERX mounted, which could easily have been done if it was felt beneficial. And you're still wrong in that a CCC position would put the canards behind the inlet.

    It worked, it just wasn't all that beneficial. The intake would have the effect of pulling more air down onto the roof of the wing and canard, increasing lift anyway.

    They were options that were cut due to budgeting. I brought the Su-47 up to show LCC and chin intakes can work but then you started fiddling with detail to progress the argument. The LERX on a Rafale does in fact combine with the canard and that starts in front of the inlet too. I don't know why I'm discussing this with you, you don't even understand air density and its affect on lift.

    Any idiot knows STR is lower at 15,000ft than SL. You first mentioned the trailing edge aspect yourself, so don't try change it now. You mentioned the trailing edge as important and then started babbling about lateral separation. You basically don't have a point, so you're straw-manning every little detail and when disproved you move to some other slight difference you can find.

    Now you're just being plain thick. I've already explained that the double delta was an attempt to have an LCC pitching effect whilst gaining CCC lift. If you remove the double delta and go back to a standard Typhoon wing, the wing ends sooner, so the canard can be moved back further.

    It just produced too much drag full-stop and increased RCS and reduced usable instability.

    Which is the exact same inlet-canard spacing that a theoretical CCC Typhoon with LERX-mounted canard would have.

    You mean like the splitter and separation that's also here?

    [​IMG]

    Not really if you try and understand what they were trying to do.

    And they had absolutely no ability to change that during the design phase if they'd wanted? You talk complete rubbish. Rafale and Gripen were multi-role fighters and went for stronger fuselage hardpoints, Typhoon went for superior intake and aerodynamic performance. Gripen had to because it's not like it can carry anything substantial on its little wings.

    The LERX becomes part of the longest bit of the wing from front to back. The vortex from the canards is fairly narrow and on the Rafale and Gripen it flows over a shorter part of the wing having less effect.

    Bwahahahahahahahahahahahaha!

    So let me get this straight, are you still claiming 28.1deg/s at 15,000ft for the Rafale C?:rofl: Even @halloweene will laugh at this. Wasn't Rafale A also abandoned in 1994?

    According to Picard:Close coupled vs long arm canard | Indian Defence Forum
    2:02 just before roll start

    [​IMG]

    2:02 just starting to roll:
    [​IMG]

    At the very moment of it turning to 2:03
    [​IMG]

    At the very moment it turns 2:04
    [​IMG]

    180deg in 1s. This is why you need 2 rolls to balance out the timing inaccuracy.

    Nowhere near enough. You find me an unstable delta without canards or tail. Canard is also providing downforce at high AoA.

    [​IMG]


    Yes but that's why the pitching arm length is beneficial. Greater moment for less force and drag.
     
  2. halloweene

    halloweene Major MILITARY STRATEGIST

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    Someone woke me up? I do not have the data so i wont laugh.

    In the end i tend to trust users (pilots)... So i do not understand how, despite your repeated convincing clues, Rafale keep spanking Eurofighter (statistically speaking) in BFM...
     
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  3. BMD

    BMD Colonel ELITE MEMBER

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    That is your opinion and the opinion of French aviation journals, which also talk shit. Meanwhile British press and British pilots say the exact opposite. Much the same as in other tests. We had a short talk about BS training exercise coverage elsewhere:

    Eurofighter Typhoon | Page 227 | Indian Defence Forum

    You can often find many different accounts of the same event. BFM consists of fake exercises in entirely fake conditions anyway.

    Meanwhile, back on the subject of STR. See page A8-54 and A8-57:

    https://info.publicintelligence.net/HAF-F16-Supplement.pdf

    It may be possible for an aircraft to achieve 28deg/s at SL but it just isn't happening at 15,000ft. The main point however, is the obvious problem with what Picard wrote. Points for guessing what it is. It shows that he knows absolutely nothing about even the basic fundamentals of lift.

    Close coupled vs long arm canard | Indian Defence Forum
     
    Last edited: Sep 4, 2014
  4. ajithharish

    ajithharish 2nd Lieutant FULL MEMBER

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  5. halloweene

    halloweene Major MILITARY STRATEGIST

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    Not journal, PILOTS! Find one british pilot saying that statistically speaking Typhoon win in BFM, i'll enjoy. And yes it is completely relevant as you keep saying that EFA aerodynamics are better...
    But of cours Grandclaudon (Sqd commander), and so many other french pilots can only be wrong, as they do not adhere to your sect...
     
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  6. somedude

    somedude Captain FULL MEMBER

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    Rafale A was a prototype and technology demonstrator. Only one was built. It was never meant to be a final production design. It's hard to call it "abandoned" and it also doesn't make much sense to keep using it as a reference; if it should be used in comparisons with Eurofighter it should be compared with the seven DAx aircraft.

    There's only three Rafales that really matter: B ("biplace", two-seater), C ("chasseur", fighter), and M ("marine", naval). Forget about A. Don't know why it's getting brought up. The Rafale A had a long and successful testing career and now rests in a museum.
     
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  7. Picard

    Picard Lt. Colonel RESEARCHER

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    Vastly less you mean, take a look at some fixes they had in mind for Typhoon's aerodynamic issues, none of which were part of the original design:

    LERX (oh, hey, Rafale)
    http://i146.photobucket.com/albums/r279/sampaix/LEX.jpg
    http://4.bp.blogspot.com/-8aaK4EBPKjM/U6vT-boJr5I/AAAAAAAADCs/LIV-Il_8Xx0/s1600/Typhoon LERX.jpg

    ALSR
    http://i146.photobucket.com/albums/r279/sampaix/image017-1.jpg

    I can't read your mind, so make sure that what you write is the same as what you think next time. Lower lip has nothing to do with position, you can just as well incorporate it in Gripen/F-15-style side intakes. In any case, intake shielding by the fuselage is more important.

    That is the same thing I am talking about. Neither Gripen or Rafale, to my knowledge, experience a significant loss of thrust at high angle of attack.

    Yes, they have:
    http://www.armscontrol.ru/atmtc/Arms_systems/Avia/Russia/Su27/su-37.jpg

    And how do you expect such placement to have been done on Typhoon?

    And with consequently lesser aerodynamic efficiency - it ended up being controllable at angles of attack up to 60*:
    Mikoyan Project 1.44 - Wikipedia, the free encyclopedia
    Compare to Gripen which can achieve 80* sustained AoA:
    MACH Aviation Magazine - på webben
    and a maximum of between 100-110* AoA. Rafale can also achieve a maximum of 100* AoA.

    Controllability at extreme angles of attack is useless by itself, but it shows efficiency of aircraft's vortex flow system and thus lift and controllability enhancement at lower AoA - stronger vortices result in A) later stall onset, b) better wing response to control surface inputs and c) higher maximum achievable angle of attack.

    And you don't understand air flow and vortex aerodynamics, so I could start ignoring you straight away?

    Not on Typhoon's configuration.

    On Typhoon it wouldn't put canards behind the inlet, which is precisely the problem - and if you understood aerodynamics better, you would have realized that it is the reason why Typhoon's canards are not of a close coupled configuration.

    Main goal - lift enhancement - was not achieved effectively, and it caused too much drag.

    These are details that have to be understood if you want to understand design choices. Su-47 does not have chin intakes, and its canard leading edge is positioned behind intakes. Ergo, no aerodynamic issues.

    1) LERX overalps with canard on Rafale but LERX itself is a lift enhancement device (a vortex generator).
    2) Rafale's canard does not start in front of the inlet, and neither does LERX; see image below.

    [​IMG]

    Nor do you understand its effect on drag, plus you refuse to understand design choices, and going from your statement above, you don't even know how one of aircraft you're discussing friggin' looks.

    Stop lying:
    Funny that none of them made it into serial production except for the J-10. And with all of them, canard leading edge was behind air intake (except for Su-37, but even there trailling edge was behind air intake, and canards were not right next to the air intake anyway).

    Yes, I did mention it, but not in the way you are saying I did.
     
    Last edited: Sep 4, 2014
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  8. Picard

    Picard Lt. Colonel RESEARCHER

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    I also mentioned leading edge as more important, and it was all about canard separation from air intakes - and in the case you didn't notice, we live in a 3-dimensional world.

    You are basically a troll with no understanding of aerodynamics. Are you a bureocrat, by any chance?

    It can't, because Typhoon's wing leading edge is nowhere near removed from intakes enough:
    [​IMG]

    Canard and wing must not overlap, which means that forward third of canard would be in front of the air intake. So they would need to both move canard backwards and extend inlet forwards. Which would mean a change in center of gravity, increased weight (even more so if they tried to maintain center of gravity), etc.

    Because of chin inlets combined with close-coupled canards.

    Except it isn't anywhere near it. Vertical spacing would be similar, but horizontal position would not.

    Rafale's separation continues all the way to behind the wing's leading edge, Typhoon's doesn't.
    http://upload.wikimedia.org/wikipedia/commons/f/fb/Rafale_RIAT.JPG
    http://upload.wikimedia.org/wikipedia/commons/6/64/RSAF_Typhoon_at_Malta_-_Gordon_Zammit.jpg

    So while Typhoon's plate and separation might have similar effect, it will not be nearly as pronounced.

    Double delta was also used on Rafale's initial design, and was given up for the same reason - straight delta is easier to manufacture, and some benefits of double delta can be emulated with LERX.

    They could have, but it would have meant starting from scratch, and they only discovered problems relatively late. Starting from scratch would have delayed delivery, and I can only guess at possible political consequences of that (it is entirely possible that some countries could have opted out of the program and decided on procuring Rafale or Gripen).

    Rafale's primary task was always air superiority, as was Typhoon's and Gripen's. All of them had similar primary requirements: STOL capability and good maneuverability.

    Empty weight as a percentage of maximum takeoff weight:
    Gripen: 49%
    Rafale: 39%
    Typhoon: 47%

    So much about Gripen being multirole by design... and even Rafale's ability to carry extremely heavy payload was more of a happy accident. Fact is, all Eurocanards were primarly air superiority fighters, as can be clearly seen by their design characteristics such as low wing loading to help high-altitude maneuverability (higher wing loading is better for ground attack).

    You are oversimplifying.

    Canard root and LERX vortices energize inner portion of the wing and move center of lift forward > increased pitch onset / turn onset rates; they also increase vertical tail effectiveness at high AoA.
    Canard tip vortices energize outer portion of the wing > increased roll onset rate.

    All mentioned sets of vortices help delay air flow separation and increase lift at high AoA (consequently increasing instantaneous turn rate), but as you said, inner set has more influence as it covers greater portion of the wing. LERX and canard root vortices also energize each other, delaying vortex breakdown and allowing wing and tail trailling edge control surfaces to remain effective for longer.

    Which is near the end of the said second, and so little time left that it is nearly irrelevant.

    You really don't know how to read photos? As a matter of fact, both Rafale's and Gripen's canards are designed to drag as little as possible at sustained turn conditions - I'd bet you whatever you want that canard in question is at 0* AoA or very near it. But you can't know at what AoA canard is unless vortices are present to show it, so your statement that canards are providing pitch-down moment in that photo is pretentious bullshit.

    Or you can leave canard unloaded and use trailling edge surfaces.
     
    Last edited: Sep 4, 2014
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  9. BMD

    BMD Colonel ELITE MEMBER

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    I've heard several pilots say it and many more have said it according to third parties.
     
  10. halloweene

    halloweene Major MILITARY STRATEGIST

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    Oh really :) . Fianlly i can slap back to your face your stupid argument : quotes in edited journals?
    (and i'm not talking BS in Eurofighter world...)

    Every data i have (and i admit they should be taken with some salt) is about absolute spanking in BFM (except for Maj. Gruene)...
     
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  11. BMD

    BMD Colonel ELITE MEMBER

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    Nope. Britain, Russia, Italy, German and Spain - vastly more intellectual resource than France and Sweden.

    [/quote]
    Yes, it was me who told you about this. This will provide all the advantages of CCC and LCC. When will you have less than 50kts EAS?

    Yes, the lip captures more air and the fuselage and shield make sure it enters the intake.

    Based on your STR comments at SL and 15,000ft your knowledge isn't worth jack.

    Nope they're just mounted on a LERX, which could easily have been applied to the Typhoon, and indeed is being.

    Add a LERX and start canard on outer edge of LERX. Simples.

    Yep, smart people. You don't need more than 60deg except for airshows.

    Thrust vectoring allows high angles of attack too, but you loose huge amounts of energy when doing it, so it leaves you a sitting duck. High AoA without TVC is no different in this respect. Planes slow down massively when they pull more than 30deg AoA. Let's face it, at 100deg, you're effectively flying backwards. If planes were supposed to fly backwards, they'd have a cockpit in their ass.

    No, it just shows that the plane can do something completely useless for airshows and doesn't demonstrate how it performs in a more rational flight regime. As I said, you get more lift with CCC but also way more drag. At higher altitudes, and larger AoAs, the plane with higher TWR and less drag will win through.

    Prove it. I proved you wrong very simply. You don't understand lift, the end. You talk about canards and vortices like you're some kind of professor but you don't even understand the effect of air density on lift.

    Sure it could, they're adding a LERX now. At the design stage, they could have put that there and then mounted the canard on the outside of it if they'd wanted but it wasn't the best air superiority solution.

    HA! You mean if I understood that less dense air at 15,000ft means less lift? I've already explained that the canards could go behind the inlets, or hell, the intakes could even be lengthened a few inches. Hardly as firm as saying, "well if we want strong fuselage hardpoints, we can't have chin inlets, which in turn means no LCC," as per Rafale and Gripen design team.

    Required bigger canards and reduced instability to increase the lift, hence no overall benefit.

    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. "

    Quite categorical and I've already shown that Gripen and Rafale canard span is much larger relative to wing span.

    Picard! Knowing the affect on air density on lift, and knowing that air density falls with altitude is something you need to understand before you even look at aircraft design. Really dude! You should go away and understand the lift equation before even posting here. Until you do, you can't possibly understand anything about aircraft design and using words like, "Ergo," won't make up for it. It's like attempting high order differential equations before being able to count to ten.

    The canard LERX does. The wing has a LERX but so does the canard.

    In all honesty, if you didn't understand the affect of air density on lift, you probably haven't got a clue about drag either. Are you surprised the aircraft all look slightly different? Because you seem to keep picking up on all the small differences. The Typhoon study was done at the design stage. At that point they were free to change anything. They could move the canard back, increase its size, reduce instability and mount it on a separate LERX like Rafale but they chose not to for reasons outlined in my link - too much drag, too larger an RCS, no overall benefit.


    QUOTE]
    Stop lying:
    Funny that none of them made it into serial production except for the J-10. And with all of them, canard leading edge was behind air intake (except for Su-37, but even there trailling edge was behind air intake, and canards were not right next to the air intake anyway).

    Yes, I did mention it, but not in the way you are saying I did.[/QUOTE]
    Looks that way to me:

    Close coupled vs long arm canard | Indian Defence Forum

     
  12. BMD

    BMD Colonel ELITE MEMBER

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    You only changed it to be about lateral separation after I picked you up on the trailing edge point. Very next post in fact, note #15, previous was #13.

    Close coupled vs long arm canard | Indian Defence Forum

    If a theoretical Typhoon CCC was mounted on a LERX, it would have lateral separation too.

    You are the clown who wrote this, indicating that you don't even understand the affect of air density on lift:

    Close coupled vs long arm canard | Indian Defence Forum

    So if you wanted CCC, you would move the canard back and mount it on its own LERX like the Rafale and you could also add a wing LERX too.

    The wing root LERXs can overlap or did the might Rafale get it wrong? Note how you can also sweep the rear of the canard. Basically with the simple changes I suggested the placement separation would be as per Rafale.

    [​IMG]

    No, it was just crap, requiring bigger canards and lower instability.

    Move the Rafale LERX onto the Typhoon, so that the forward edge is level with the intake start as per Rafale. Add a canard LERX in between canard and fuselage. Add small LERX to wing and voila Eurofale. Of course as a result of this move, you need to move the whole wing back anyway, because you have to reduce the instability margin having reduced the canard pitching arm. So of course, your whole argument is invalid, yet again.

    Add small LERX and then it does.

    Exactly.

    How do you know when it was discovered. The document was written when BAE SYSTEMS was still British Aerospace. The document discussed the issue of increasing lift but needing to reduce instability. That would require moving the whole wing, which is a far bigger change than lengthening an intake, so the document is obviously examining design decisions that took place fairly early on when the design was fluid. Probably late '80s, early '90s.

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

    Nope, Dasault say specifically 'Omni-role by design' see:

    Omnirole by design - Dassault Aviation

    Clearly a marketing exercise at Typhoon's expense because they know Typhoon is an air superiority fighter playing multi-role when required, which is not what many customers want, although it is vastly more important.

    Show me any fighter carrying more than 16,530lbs and I'll give a shit. I've never even seen a Strike Eagle carry that much.

    Gripen is multi-role but it's very light and small and single-engined, so that limits it load bearing ability. 'Omni-role by design' is a massive accident? :facepalm::rofl:

    All I implied was that increasing lift over the longer part of the wing is more effective.

    Yep, but we know that the 2:03 clip is at the very start of that second because of the 2:02 clip showing the roll starting. At 2:04 it has turned through exactly 180deg in 1s (or more) from the 2:03 clip. So your roll rate argument fails.

    I can tell from the picture it isn't. It's at negative AoA to provide downforce and counter the instability.

    Spot the difference:

    [​IMG]
    [​IMG]
    [​IMG]


    Which clearly isn't what Gripen is doing because they don't provide anything like as much force.
     
  13. somedude

    somedude Captain FULL MEMBER

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    I didn't know Russia collaborated to the Eurofighter project, that's really interesting! :p

    Russia also designed CCC fighters, so they're moot. Israel designed CCC fighters, so you can add them too.

    It's a very meaningless appeal to authority, too. "Four countries worked on making that plane, so it's better than planes made by one single country!" It's not how things work. Too many cooks spoil the broth.

    You give far too much importance to slogans and marketing catchphrases.

    The Rafale, however, was indeed always meant to be a multirole aircraft. The idea was that it would be able to replace all the fighter types used by the ADLA and the AN; it was meant to replace Mirage III, Mirage IV, Mirage 5, Mirage 2000, Mirage F1, Super Etendard, F-8 Crusader... However, it entered service first as an air-to-air fighter because that was the most urgent need (once you have air supremacy, you can use old bomb trucks to attack the ground relatively safely after all) and it allowed to stagger weapon integration costs nicely. F1: air to air, F2: recon and ground attack, F3: nuclear strike.

    So, you're not wrong on that point, but try to base your argument on facts rather than marketing. After all, the Eurofighter Typhoon's slogan is "nothing comes close" but a Learjet 35A did...
     
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  14. BMD

    BMD Colonel ELITE MEMBER

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    Talking about their other canard designs. I could also throw in China's J-20.

    Not with moving foreplane, unless you mean the one they passed on to China???

    Picard is trying to make out that the Typhoon's long coupled canards are inferior. Despite thinking planes have a higher sustained turn rate at 15,000ft than sea level, he thinks he's an expert on aerodynamics.

    I judge whether they're true and in the Rafale's case it is. This is the reason for the strong fuselage hard points and side intakes. Hard points mounted on intakes aren't as strong.

    Appreciated. Eurofighter GmbH often try to advertise the Typhoon as multi-role and to a certain extent it can do multiple roles, but it was always designed primarily for air superiority.
     
    Last edited: Sep 5, 2014
  15. Picard

    Picard Lt. Colonel RESEARCHER

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    You are, as usual, wrong.

    Countries that have opted for close-coupled canard designs:
    France
    Sweden
    Russia
    United Kingdom
    Countries that have opted for long-arm canard designs:
    Germany

    And yes, UK proposal for Eurofighter was a close-coupled canard:
    https://defenseissues.files.wordpress.com/2014/09/bae-ps.jpg
    https://defenseissues.files.wordpress.com/2014/09/aca.jpg
    https://defenseissues.files.wordpress.com/2014/09/baep1062xd9.jpg

    In fact, original German design was too, but they switched it to long arm configuration once it became obvious it doesn't work with configuration they chose:
    https://defenseissues.files.wordpress.com/2014/09/tfk901983.jpg
    https://defenseissues.files.wordpress.com/2014/09/m1a7g.jpg

    Other Eurofighter partners don't count since they had little input in design other than basic requirements.

    You are not center of the universe you know, I knew about it for long time now (from before you registered on forum, in fact). But it is not operational yet.

    Some advantages, but not nearly all of them.

    Hopefully never, but in a one-on-one and two-on-two fights it can happen (Rafale was flown at speeds as low as 18 kts against Mirage 2000).

    Rafale's air intakes are also shielded, against both high AoA and sideslip.

    You can't mount canards on LERX, not in Typhoon's design at least, as wing is too thin and section is too shallow:
    http://www.ausairpower.net/VVS/000-Su-37-1S.jpg
    http://i825.photobucket.com/albums/zz176/Theg777/Typhoon-DA5-RBS-15.png

    Canards would have to be so small that they would not have large effect anyway.

    Maybe you don't understand it, but reduction in aerodynamic responsiveness is gradual, especially for similar configurations. Rafale and Gripen can reach 100+ degrees AoA, and so can be expected to be more responsive to control inputs even at lower angles of attack.

    Ability to achieve extreme angles of attack based on aerodynamics alone (so no TVC) showcases characteristics that are required even at low to moderate angles of attack:
    1) late stall onset
    2) slow stall progress
    3) high control surface effectiveness

    Of course, being able to achieve high AoA is no indication of performant aircraft, and lack of it does not mean that aircraft cannot perform well, but that is typically dependant on factors not connected to ones listed - and some of these factors are irrelevant for tailless configurations (twin-tailed aircraft tend to have good high AoA performance regardless of overall aerodynamic performance, though even there aircraft with better aerodynamics tend to be capable of achieving higher AoA - ref. Su-27 vs F-15).

    More drag in level flight yes, not so much when turning since CCC improves lift/drag ratio compared to canardless configuration:
    http://www.dtic.mil/dtic/tr/fulltext/u2/a245152.pdf
    "This thesis has shown that a properly located close-coupled canard can greatly enhance lift at high angles of attack with no drag penalty when compared to a wing/body configuration."

    I already have, and you have an example just above.

    Your entire "you don't understand" bullshit is based on intentional cherrypicking - as I have already explained, these figures were from two different, completely independent sources, and were simply meant to show that you are wrong about Typhoon's major advantage in sustained turn rate regardless of which source you pick.

    And lift is not the only parameter important for sustained turn rate. For instantaneous turn rate, yes, but for sustained turn rate improvement in turn rate due to increased air density can be offset by increased drag. Thrust will increase, true, but what matters is lift to drag and thrust to drag ratios, and for different configurations and different engine types, all of these change at different paces regarding altitude. Turbofans perform better at low speeds and low altitudes, for example, whereas turbojets perform better at high speeds and high altitudes. Typhoon's variable air intake will be help at high altitude, but not so much at low altitude. So while lower altitude will still improve turn performance, rule of thumb you used is bullshit, as can be clearly seen here:
    http://www.worldaffairsboard.com/at...ormance-actual-plane-analysis-37000lbs220.png

    Coplanar close coupled canard is far less effective than one mounted above the wing.

    Canards couldn't go behind the inlets, as for lenghtening the intakes, that would mean adding more weight to an already overweight design (they'd need to add weight somewhere to the rear of Cg in order to maintain its position).

    Only relevant for that particular configuration, which had less than optimal performance (unfavorable interference between air intakes and canards destroying lift).

    You don't understand basics of drag, importance of lift and responsiveness to control surface inputs, and you also don't know what LERX (leading edge root extension, for future reference) is.

    And I also clearly mentioned leading edge as more important, while trailling edge was a main differentiating characteristic with Su-37, as it is unique among canard configurations in that its canard's leading edge is in front of the air intake, but trailling edge isn't.

    Typhoon has no such separation, so it is irrelvant for why Typhoon ended up with long arm canard. But you insist on bringing up strawmans.

    Do you even know what LERX is?

    [​IMG]

    You can't mount canard on LERX, there is no room for actuators. Unless of course canard is fixed, but that carries its own set of problems, and LERX itself is aerodynamic structure, like canard. If you did mount canard on where Typhoon's LERX will be positioned, you'd have a very small coplanar canard, hardly an ideal solution. In order to have a properly positioned canard, you'd have to expand basic body structure sideways, at which point you can as well adopt Rafale-style intake placement in order to insulate them, so that any adverse conditions at one air intake do not affect another.

    LERX is intended to generate vortices that improve lift on the main wing, not to increase wing area. So yes, it can overlap with canard.

    Sweeping the rear of the canard would have made little difference in that respect unless it allowed canard leading edge to be behind the air intake. Which depends solely on canard placement and canard root length.

    Besides, all three Eurocanards already have swept trailling canard edge:
    http://defenseissues.files.wordpress.com/2014/01/visual.jpg
    http://upload.wikimedia.org/wikipedia/commons/2/2b/Armée_de_l'Air_Rafale.jpg
    http://www.aerospaceweb.org/aircraft/fighter/gripen/gripen_08.jpg
    http://www.worldofstock.com/slides/WOS18908.jpg
     
    Last edited: Sep 8, 2014
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