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  • Shania
    Rank 5 Registered User
    • Jan 2017
    • 34

    Any news about CEC capabilities of Rafale?

    Comment

    • halloweene
      Rank 5 Registered User
      • Jan 2012
      • 4337

      Originally posted by Scorpion82 View Post
      Thanks. Wrt to LDP/HMD integration has there been any details?
      According to an Istres test engineer from Istres i will of course ot cite, announcement should be done at PAS19. Most of the work is done.

      Comment

      • ThincanKiller
        Registered User
        • Feb 2019
        • 91

        Originally posted by garryA View Post

        For your information, a controlled departure is not the same as combat rated PSM, because to be able to utilize PSM, the accuracy of the yaw/pitch is important
        LOL! Here we go again, you lack so much critical mind and understanding of the basics of aerodynamics, you can't even figure the commercial B.S from the reality of flight , let alone combat, controlled departure means accuracy of the yaw/pitch axis.

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        Only 5th generation fighters like the F-35 and Lockheed martin F-22 Raptor can execute high AoA pedal turns
        Smell commercial B.S by the bucket, first it doesn't say "but this is only because other A-F and Navies have chosen to limit their A-C AoA to 30* or 29* after testing the Operational usefulness of PSM".

        Then, WHERE does L.M says it is anything like "combat rated PSM" and speaking of accuracy of yaw/pitch, Gripen has demonstrated being superior to F-35, relaxed AoA doesn't fix inferior aerodynamics.

        Just a little reminder:

        1) They admit to one fact, F-22 is better than F-35 in the PS area and yet no F-22 pilot uses those otherwise than to bluff fanboys at airshows and produce pretty videos, a Rafale can beat a F-22, so I don't think they are so impressed by F-35 stunts.

        2) Regardless of what you can come up with, since they did NOT conduct those test for the purpose of validating"combat rated PSM", there is no consencus (quiet the opposite) in the F-35 users, otherwise said, NO specific tests, NO "rating" and in reality PSM remains strictly limited in combat when it comes to its usefulness.

        3) X-31 pilots opinion proves and validate this point, and this A-C was designed AND tested specifically for validating and "rating" PSM.

        4) Gripen has a lot more PSM capabilities due to a higher level of control in the same yaw spin situation (but not only), without loss of control throughout the whole of the maneuver, and 30*/sec higher yaw rate demonstrated.

        5) I reiterate. ANY A-C going through spin testing successfully has "accuracy" of the yaw/pitc axis, or else, they would be able to a) increase yaw rate or other axis parameter for the purpose of the test, then stop it, and as a matter of FACT it takes the yaw/pitch controls to achieve that, increasing/lower AoA and yaw rate.


        If you had known anything about the whole subject you would be able to distinguish between commercial hype and reality.




        Last edited by ThincanKiller; 28th February 2019, 13:48.

        Comment

        • ThincanKiller
          Registered User
          • Feb 2019
          • 91

          As seen in a French forum.

          Parly also announced a 115 million contract for a feasibility study, dubbed Turenne 2, in which Safran will develop new turbine blades for the M88 engine, which powers the Rafale fighter jet.

          The new blades are expected to boost the M88s thrust to nine tons compared to the present 7.5 tons.

          https://sldinfo.com/2019/02/an-updat...february-2019/
          I personally takes this with a pinch of salt, I'd rather believe, in view of the previous stages of development, that the compressor aerodynamics, already studied for some time, are the last part of a multi-stage development phase which went through redesign of the engine modules, which first allowed for longer TBO then reduced SFC.

          So at the end, when all the components will be available, the engine will have the capability to produce 9 ton thrust but lose in terms of SFC and part longevity, though I think it might be possible to increase the thrust to 8 tons and reach a good compromise.

          Comment

          • garryA
            Rank 5 Registered User
            • Dec 2015
            • 1120

            Originally posted by ThincanKiller View Post
            LOL! Here we go again, you lack so much critical mind and understanding of the basics of aerodynamics, you can't even figure the commercial B.S from the reality of flight , let alone combat, controlled departure means accuracy of the yaw/pitch axis..
            That rich coming guys who was proven wrong over 15 times, i love how you are so desperate to save face that you resort to tactic like lying and casually skipping important evidences that your objectors put up. What happened?, why didn't you address the LM test report? ah yes, because it make you look like an idiot with what you claimed earlier.


            Originally posted by ThincanKiller View Post
            Smell commercial B.S by the bucket, first it doesn't say "but this is only because other A-F and Navies have chosen to limit their A-C AoA to 30* or 29* after testing the Operational usefulness of PSM"
            Then, WHERE does L.M says it is anything like "combat rated PSM" and speaking of accuracy of yaw/pitch, Gripen has demonstrated being superior to F-35, relaxed AoA doesn't fix inferior aerodynamics.
            Just a little reminder:
            1) They admit to one fact, F-22 is better than F-35 in the PS area and yet no F-22 pilot uses those otherwise than to bluff fanboys at airshows and produce pretty videos, a Rafale can beat a F-22, so I don't think they are so impressed by F-35 stunts.
            2) Regardless of what you can come up with, since they did NOT conduct those test for the purpose of validating"combat rated PSM", there is no consencus (quiet the opposite) in the F-35 users, otherwise said, NO specific tests, NO "rating" and in reality PSM remains strictly limited in combat when it comes to its usefulness
            3) X-31 pilots opinion proves and validate this point, and this A-C was designed AND tested specifically for validating and "rating" PSM.
            4) Gripen has a lot more PSM capabilities due to a higher level of control in the same yaw spin situation (but not only), without loss of control throughout the whole of the maneuver, and 30*/sec higher yaw rate demonstrated.
            5) I reiterate. ANY A-C going through spin testing successfully has "accuracy" of the yaw/pitc axis, or else, they would be able to a) increase yaw rate or other axis parameter for the purpose of the test, then stop it, and as a matter of FACT it takes the yaw/pitch controls to achieve that, increasing/lower AoA and yaw rate.
            If you had known anything about the whole subject you would be able to distinguish between commercial hype and reality.
            Regarding the AoA limit, let me ask you this: Does Russia limit their fighter AoA to 29-30 degrees? Does USA limit their fighter AoA to 29-30 degrees? Does Indian limit their fighter AoA to 29-30 degrees? Does Australia limit their fighter AoA to 29-30 degrees?..etc the answer is NO. (Though it is a bit of dishonest advertise by saying only 5 gen can perform pedal turn)
            To find where LM state post stall maneuver for combat is simple, you only have to look at their test report, i know you can't read very well so i have highlighted them
            Click image for larger version  Name:	image_260770.png Views:	0 Size:	837.7 KB ID:	3853720
            Speaking of accuracy for yaw/pitch, no Gripen have never demonstrated being superior to F-35, what happened is that Gripen departure test had higher spin rate than F-35 departure test (then again, so was F-18 and F-16), but that isn't the indicator of accuracy, and it wasn't really all that special either, spin rate can be accumulated overtime, you can reach high rate if you spin around several time, but it combat, that never happen. Nevertheless, a controlled departure is not the same as a PSM that can be translated to a gun/missile solution.

            1) F-22 and F-35 does uses post stall maneuver in exercise though it is not the main point about them, but to be Frank, your argument is quite dumb, 1 Rafale beat 1 F-22 in mock dogfight that mean Rafale automatically better than F-22 now? what sort of idiot think that? a F-4 did beat a Rafale in Frisian flag, should we put it as the ultimate fighter?
            2) Unlike you, who desperately try to interpret Gripen spin departure test as Post stall maneuver capability even though neither Gripen pilot nor SAAB claimed such a thing, i don't have to come up with anything, Lockheed Martin test say it all: F-35 can use post stall maneuver to gain advantage in air combat, F-35 retain post stall maneuver capability from its brother F-22, and they also list several maneuvers it could perform. That not to mention pilot who described how he used pedal turn in mock dogfight. Also, FYI, they did test high AoA maneuvers for F-35, you are trying to dismiss such obvious fact in the face of overwhelming evidence only make you look super desperate
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            3) As usual, you are very disingenuous, they didn't said post stall was useless, they didn't support trading off others important fighter characteristic just to get post stall capability that means for example: it is not worth it to cut your speed in half to get post stall capability. PSM for aircraft, can be seen as similar to a sniper having a hand gun, he will rarely use it, but in some case, it can still be useful.
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            4-5) Nope, you can repeat that a thousand times, it still won't change the fact that Gripen has no combat PSM capability, nor was it ever tested for such thing. SAAB never claimed Gripen has full control to transit from a PSM to a gun solution, only that it can be put into a spin then recover, that it. You want to prove Gripen can utilize post-stall maneuver, go find a single test report of SAAB saying such a thing about Gripen, instead of desparately trying to interprete controlled departure test as PSM
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            Last edited by garryA; 28th February 2019, 17:10.

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            • halloweene
              Rank 5 Registered User
              • Jan 2012
              • 4337

              Originally posted by ThincanKiller View Post
              As seen in a French forum.



              I personally takes this with a pinch of salt, I'd rather believe, in view of the previous stages of development, that the compressor aerodynamics, already studied for some time, are the last part of a multi-stage development phase which went through redesign of the engine modules, which first allowed for longer TBO then reduced SFC.

              So at the end, when all the components will be available, the engine will have the capability to produce 9 ton thrust but lose in terms of SFC and part longevity, though I think it might be possible to increase the thrust to 8 tons and reach a good compromise.
              Take it with a bucket of salt. Temps cited are way inferior to those tested and noone ever talked about a 9T (or less or even more) dry thrust engine. Presently these tests are more drone oriented in order to disminish the dismounting/opening of traps etc rate.

              Comment

              • ThincanKiller
                Registered User
                • Feb 2019
                • 91

                Originally posted by garryA View Post
                Regarding the AoA limit, let me ask you this: Does Russia limit their fighter AoA to 29-30 degrees? Does USA limit their fighter AoA to 29-30 degrees?

                ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ZZZZZZZZZZZZZZZZ.

                Bucked of commercial B.S for fanboyz revisited.

                Answers are simple, already gave them but fanboyz can't read properly, they only can interpret, and YES F-16 is even more AoA limited than Rafale or Gripen, other than that, it is plain obvious that they won't pass those airshow stunts in combat because it makes them slow, energy-less targets, they didn't with F-22, they won't do it with F-35 which is inferior to it PS.

                Repeat all you wish what you chose to believe, FACT is, Gripen passed a PSM with a yaw rate 30* higher than F-35, NOT at 50* AoA but between 70* and 80* AoS, meaning NOT High AoA but well past departure AoA.

                They also stalled the A-C dynamically using pitch control, meaning they started the maneuver with FULL control of it throughout and stopped it, when L-M test pilots speaks of loss of control, should be clear enough but you're unable to comprehend what it means.

                And i'm done arguning with you since you obviously don't comprehend what is written in the first place (high AoA vs Post Stall for a starter), as I first said, their stunt is advertised as high AoA, even the air show one, and the goal of those tests were high AoA, never to test PSM and validate them for combat, even if S-H does it, it doesn't make them so hot in ACM, this bit obviously is the commercial B-S-ing that get the crowd behind the manufacturer, unfortunately, they overdone it, some of us knows what spin tests implies even if you don't.

                End of your wet dream methink.
                Last edited by ThincanKiller; 1st March 2019, 13:47.

                Comment

                • garryA
                  Rank 5 Registered User
                  • Dec 2015
                  • 1120

                  Originally posted by ThincanKiller View Post


                  ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ZZZZZZZZZZZZZZZZ.

                  Bucked of commercial B.S for fanboyz revisited.

                  Answers are simple, already gave them but fanboyz can't read properly, they only can interpret, and YES F-16 is even more AoA limited than Rafale or Gripen, other than that, it is plain obvious they they won't pass those airshow stunts in combat because it makes them slow, energy-less targets, they didn't with F-22, they won't do it with F-35 which is inferior to it PS.

                  Repeat all you wish what you chose to believe, FACT is, Gripen passed a PSM with a yaw rate 30* higher than F-35, NOT at 50* AoA but between 70* and 80* AoS, meaning NOT High AioA but well past departure AoA.

                  They also stalled the A=C dynamically, meaning they started the maneuver with FULL control of it throughout and stopped it, when L-M test pilots speaks of loss of control, should; be clear enough but you're unable to comprehend what it means.

                  And i'm done arguning with you since you obviously don't comprehend what is written in the first place (high AoA vs Post Stall for a starter), as I first said, their stunt is advertised as high AoA, even the air show one, and the goal of those tests were high AoA, never to test PSM and validate them for combat, even if S-H does it, it doesn't make them so hot in ACM, this bit obviously is the commercial B-S-ing that get the crowd behind the manufacturer, unfortunately, they overdone it, some of us knows what spin tests implies even if you don't.

                  End of your wet dream methink.
                  Laughable for a troll such as you to call test report commercial BS but theory that himself come up with as fact.
                  Even funnier when you pretend like every single countries i mentioned earlier only use F-16, do you think that people won't noitice when you skip out: F-18 E/F, F-35, F-22, Su-27, Su-30MKI, Su-30MKK, FGFA, Su-35, Su-57? I have never said PSM is some sort of super silver bullet in close combat, nor did i ever claimed it is the strongest point of F-35. But PSM can be useful in some conditions that why many countries still keep it
                  To honest though, it is sad how you keep making claims that you can't back up then have to keep changing your claims over and over until you lose any credibility you ever got, like how you have to keep changing your claim from " f-35 has never beeen tested anywhere close to 90 degree AoA" then to " F-35 was only tested in spin recovery " then to " F-35 can't perform PSM, because it lose control at high AoA," then now to "F-35 PSM is inferior to F-22 so it will never be used in combat ". That desperation is both hilarious and sad at the same time.
                  FACT:
                  according to SAAB, they tested Gripen in an intentional departure test to verifed high AoA limit and spin recovery control system. There was never been a single word from SAAB themselves or Gripen pilot claiming Gripen can use post stall maneuver to gain advantage in combat (clearly opposite of what LM and F-35 pilot talk about F-35).

                  Just because Gripen was put to higher yaw rate then recover, doesn't indicate more accurate control than f-35, after all, F-16 can recover from 120deg/sec yaw rate and F-18 can recover from 100deg/sec yaw rate. You now gonna claim "but ..but ..but Gripen get to that yaw rate by its arelions input". It doesn't matter because higher yaw rate can just be accumulated, as long as the side drag isn't too high, the rate will keep increasing, you don't know how many spin does it take to get to 90 deg/second, you don't know in how many second gripen can stop if the pilot wanted to. In other words, that number impress no one but you.



                  Comment

                  • Shania
                    Rank 5 Registered User
                    • Jan 2017
                    • 34

                    At its maximum angle of attack, the F-35 reacts more quickly to the pilots "pedal inputs," which command the nose of the plane from side to side, than does the F-16, according to Hanche.

                    "This gives me an alternate way of pointing the airplane where I need it to, in order to threaten an opponent," Hanche wrote. "This 'pedal turn' yields an impressive turn rate, even at low airspeeds. In a defensive situation, the 'pedal turn' provides me the ability to rapidly neutralize a situation, or perhaps even reverse the roles entirely."


                    --
                    Like any other modern fighter, FCS dont let F-35 depart... Gripen and Rafale claws laws are more strict, it doesnt matter what they can do in testing, operational jets cant do what F-35 can.

                    Comment

                    • TomcatViP
                      Rank 5 Registered User
                      • Nov 2011
                      • 6049

                      In fact at max aoa (32 or 35deg - I have to check it back), the Rafale is locked in roll and yaw. This also mean that roll acceleration are tempered leading to what can be called: "l'effet bote meuh" .

                      Similar value for the SH is 50deg.For the Tomcat this was 42/45. F-15 is 32. F-16 30. M2K is around 25/28. Once again data are straight from my memory.

                      We have often debated this subject already. I am sure this can be accessed via a proper search on the forum

                      modern US assumption regarding max AoA is the max angle where the aircraft can roll around its velocity vector. This has never been the case at Dassault (or never publicized).
                      Last edited by TomcatViP; 2nd March 2019, 14:36.

                      Comment

                      • ThincanKiller
                        Registered User
                        • Feb 2019
                        • 91

                        Originally posted by halloweene View Post

                        Take it with a bucket of salt. Temps cited are way inferior to those tested and noone ever talked about a 9T (or less or even more) dry thrust engine. Presently these tests are more drone oriented in order to disminish the dismounting/opening of traps etc rate.
                        I thought ECO demonstrator had already reached 20.000lbs a long time ago?

                        No mention of drone either, in fact, it's either 20.000lbs or SFC/TBO etc, if the engine is capable of it with a redesigned compressor (they spoke of internal aerodynamics at the time), it matters little what they use it for.

                        Comment

                        • halloweene
                          Rank 5 Registered User
                          • Jan 2012
                          • 4337

                          Italked 2 years ago with a tech at DGA propulseurs about it (he is in the same aeroclub as me) . The very hih temps tested during Turenne 1 were not specifically designed for M88, ut for SCAF DP (the drone) engine. And they were reaching higher temps. Talking later with ppl from Safran or DA, this temp higher tolerance was more designed to improve visits rythm so as to help drone stealthiness.
                          About Turenne 2, yes it is probably meant to NGF or a new version of M-88, didn't heat anything about a 9T prototype although.
                          Yes ECO demonstrator reached 9T, but at the cost of a poorer reliability than M-88 CGP pack. Thins are moving quickly although. But i'm afraid someone may have mixed projects. Presently, many said that due to airflow amount dictated by air intakes, M-88 could not go further than 8.3 T on present Rafale.
                          Thins are moving so quicly i may have lost a track.

                          Comment

                          • ThincanKiller
                            Registered User
                            • Feb 2019
                            • 91

                            Originally posted by TomcatViP View Post
                            In fact at max aoa (32 or 35deg - I have to check it back), the Rafale is locked in roll and yaw. This also mean that roll acceleration are tempered leading to what can be called: "l'effet bote meuh" .

                            Similar value for the SH is 50deg.For the Tomcat this was 42/45. F-15 is 32. F-16 30. M2K is around 25/28. Once again data are straight from my memory.

                            We have often debated this subject already. I am sure this can be accessed via a proper search on the forum

                            modern US assumption regarding max AoA is the max angle where the aircraft can roll around its velocity vector. This has never been the case at Dassault (or never publicized).
                            No secret here, it matters little which AoA you are at low speed to achieve this if: a) structural integrity of the airframe allows b) depending on your particular A-C aerodynamics, your yaw axis will be controlled by either one set of control surfaces or another, (adverse, induced etc).

                            On Close-coupled canards (or ANY canard surfaces equipped A-C), there is no use of the canard surfaces in the roll axis for reasons of structural torsion (it would require a much too heavy front fuselage), on the other hand, as demonstrated on Mirage IIIS/NG/4000 and IAI Kfirs (close-coupled), the airflow on the fuselage, boundary layer at the A-C wing roots and around the vertical surface is enhanced/energized by the presence of vortexes from nose cone strakes/LEX/Delta wing root, canard root and on the Rafale, the design of the fuselage itself.

                            So you have several sets of vortexes to keep the boundary layer on the airframe in this area, meaning vortexes breakdown occurs at much higher AoA.

                            That's a particular characteristic of the design which seems to elude to many people writing about it, at high AoA, the boundary later sticks to this part of the fuselage when that of conventional designs have already vacated, not the case of Close-coupled canards, no need to consult in forum but to read studies about the formula from people who knows, like NASA/DRYDEN/Dassault/SAAB, interpretation if forum is much too often tainted and inaccurate.

                            There is NO "effet bote meuh" there, NO aerodynamic limitation if this is what this B.S means to some, quite the opposite, if you mistake acceleration with roll rate, as explained hundred of time by people who served in A-F using them, limitations are there to allow for your average squadron pilot to keep the A-C under control at all speed, since there is no speed limiter for example, and btw, the Mirage 2000 is also limited this way, even more in G than a Rafale.

                            btw, on F-18/F-35. vortexes breakdown in the area is also well documented (fluter/structural issues caused by aerodynamic bashing), so whatever AoA they will reach, they will not be as efficient as that of a close-coupled canard, even with the use of 2 vertical fins.

                            So you guys can keep the effet bote meuh for confetis to throw at weddings because it's what it's worse, bar if you want to keep flaming French posters in forums.

                            Max AoA is another topic altogether, on Rafale it has little to do with aerodynamic limits, but on performances limits, the A-C is perfectly controlable PSM but the reality is; how much energy are you prepared to trade for just a maneuver you actually can pass at 29* AoA?

                            You don't need 30/40/50* AoA to do a pedal turn, all you need is low speed, at whatever AoA your A-C will allow you to pass the maneuver, so if you have the choice between transcient performances (energy/acceleration) and AoA which will take it all away from you, and become more of a limiting factor than an advantage, limiting the A-C AoA makes perfect sense.

                            Conclusions of PSM tests were the same than those reached by X-31 pilots with on top the comment made by Yves Kerherve; "we don't need TVC".
                            Originally posted by Shania View Post
                            At its maximum angle of attack, the F-35 reacts more quickly to the pilots "pedal inputs," which command the nose of the plane from side to side, than does the F-16, according to Hanche.
                            F-15 is far from being an example at this level, first it is the most AoA limited quoted so far, then it suffers from limitations such as superstall and departure in transonic which close-coupled canards doesn't know, and it is not the only one A-C with this sort of characteristics.




                            Originally posted by Shania View Post
                            "This gives me an alternate way of pointing the airplane where I need it to, in order to threaten an opponent," Hanche wrote. "This 'pedal turn' yields an impressive turn rate, even at low airspeeds. In a defensive situation, the 'pedal turn' provides me the ability to rapidly neutralize a situation, or perhaps even reverse the roles entirely."
                            --
                            Like any other modern fighter, FCS dont let F-35 depart... Gripen and Rafale claws laws are more strict, it doesnt matter what they can do in testing, operational jets cant do what F-35 can.




                            Actually, bar going over 29/30* AoA, yes they can, because you don't need to get into a stall to do a pedal turn, you can do it in a stall though.

                            And even more efficiently, as demonstrated by Gripen maximum yaw rate in yaw spin tests, 30*/sec is a huge difference when it comes to 60* to 90*, but there is little advantage in ACM there, if 1) you lose your energy, 2) you're at AoA where recovering it is going to take more time than a F-16 pilot needs to drill your brain out in a gun-only contest, reason why the top guns flying F-22 doesn't even try it even so their TWR is so much higher than a Rafale in ACM.

                            There is a point where one has to distinguish between commercial bragging and reality (Gripen and Rafale are still F-35 competitors).
                            Last edited by ThincanKiller; 3rd March 2019, 13:23.

                            Comment

                            • ThincanKiller
                              Registered User
                              • Feb 2019
                              • 91

                              Originally posted by halloweene View Post
                              Yes ECO demonstrator reached 9T, but at the cost of a poorer reliability than M-88 CGP pack.
                              Not particular to M88, it's either one or the other with every engine, but only a 10 ton version would require redesign of the engine and intakes if my memory doesn't fail me, SNECMA at the time published a PDF on the CGP pack and the stages used to get there, again by memory, the aerodynamics of the compressor and perhaps other internal parts were mentioned as well.

                              By that you can read, increased pressure/output but also better cooling, topics researched by ONERA together with material coating for higher TIT.
                              Last edited by ThincanKiller; 3rd March 2019, 11:20.

                              Comment

                              • TomcatViP
                                Rank 5 Registered User
                                • Nov 2011
                                • 6049

                                it matters little
                                Yes very much that.

                                Comment

                                • ThincanKiller
                                  Registered User
                                  • Feb 2019
                                  • 91

                                  Originally posted by TomcatViP View Post
                                  Yes very much that.
                                  If you train to stall different A-Cs in order to know their specific limits, you'll figure that they often have different stall characteristics, mostly an AoA where you shouldn't use ailerons (or else you stall one wing earlier than the other one) but rudder instead and it depends on the design itself.

                                  Take this a step further and this is precisely how you depart an A-C asymmetrically (as demonstrated by the descriptive of the yaw spin test on Gripen), start a yaw spin and stop it, you'll also need to recover speed, meaning using pitch, and all of this at AoA much lower than that reached by F-18/35.

                                  I tried to explain this from the start, there is a consensus about stall which involves AoA only, but stalling doesn't necessarily mean that all airflow have left your wing surface, since the loss of lift is the result, it can occur because of speeds at which air pressure doesn't allow for enough lift to be generated, as I said previously, you can stall an A-C in many ways, AoA, AoA and speed combined or speed only, even at 0* AoA as you will do when you pass a Hammerhead maneuver.

                                  In every case you will learn the most important factor for recovery is speed, so energy management is the buzzword here, not maximum AoA or how much AoA your FCS will let you get to, in theory, an F-22 is much more controllable than a conventional A-C at this level, it doesn't prevent a Rafale without TVC and with a much lower TWR to compete with it, the Rafale pilot will always be able to point its nose toward the F-22 at low speed but it doesn't need 50* AoA, using vertical yo-yo will allow you to manage your energy level.

                                  The A-C recovers speed very fast when you trade altitude for energy and looses little at high AoA (same at high G btw) while still remaining maneuvrable enough, I know it can do pedal turns since I have seen Kerherve do that at Farnborough with the Rafale M, but you will put the AC in an attitude where energy recovery will take more time than with a conventional high yo-yo, no advantage there, he only passed it to demonstrate low speed maneuverability of the Marine version, little interest otherwise.

                                  The HUD footage of the ACM between Rafale and F-22 should have given people a clue, because if you can roll at 80kt without TVC at the top of your yo-yo, there is little advantage keeping this low level of energy since you can keep pointing nose while recovering it.
                                  Last edited by ThincanKiller; 3rd March 2019, 12:16.

                                  Comment

                                  • FBW
                                    FBW
                                    Rank 5 Registered User
                                    • Dec 2011
                                    • 3295

                                    Dassault Rafale discussion with pilot on fighter pilots podcast. Interview starts at 17 min.
                                    https://www.fighterpilotpodcast.com/...ssault-rafale/

                                    Comment

                                    • ThincanKiller
                                      Registered User
                                      • Feb 2019
                                      • 91

                                      Originally posted by FBW View Post
                                      Dassault Rafale discussion with pilot on fighter pilots podcast. Interview starts at 17 min.
                                      https://www.fighterpilotpodcast.com/...ssault-rafale/
                                      Interesting, thanks.

                                      I would have loved it if it had been an interview of Kerherve or any of the DGA/Dassault test flight team, unfortunately, as much about France's stuff, it's advertised briefly when it comes out, then get classified, so if you missed it, haven't archived it, you just aren't informed.

                                      Anyway, it's a little bit "all public", but what we have confirmed is: M 1.4 supercruise and 11.0g.

                                      When I say "all public"I mean little details about what he means by air-to-air configuration, as for F-16, two wingtip AAM is considered as "clean".

                                      About the "airbrake" effect of the delta wing, again "all public", you can use it as an airbrake at max AoA, sure thing, but what is not said is; close-coupled canards allows for lower AoA for the same amount of vortex lift (appears earlier in the AoA scale), therefore, higher lift/drag coefficient.

                                      The A-C drags less and loses much less energy for the same amount of G than a Mirage 2000 with similar TWR (dry thrust it will beat a 2000 in full reheat), it will recover its energy faster because for the lift needed for the same maneuver it will take less AoA in every situation as well.
                                      Last edited by ThincanKiller; 3rd March 2019, 14:17.

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                                      • garryA
                                        Rank 5 Registered User
                                        • Dec 2015
                                        • 1120

                                        Originally posted by ThincanKiller View Post

                                        No secret here, it matters little which AoA you are at low speed to achieve this if: a) structural integrity of the airframe allows b) depending on your particular A-C aerodynamics, your yaw axis will be controlled by either one set of control surfaces or another, (adverse, induced etc).
                                        On Close-coupled canards (or ANY canard surfaces equipped A-C), there is no use of the canard surfaces in the roll axis for reasons of structural torsion (it would require a much too heavy front fuselage), on the other hand, as demonstrated on Mirage IIIS/NG/4000 and IAI Kfirs (close-coupled), the airflow on the fuselage, boundary layer at the A-C wing roots and around the vertical surface is enhanced/energized by the presence of vortexes from nose cone strakes/LEX/Delta wing root, canard root and on the Rafale, the design of the fuselage itself.
                                        So you have several sets of vortexes to keep the boundary layer on the airframe in this area, meaning vortexes breakdown occurs at much higher AoA.
                                        That's a particular characteristic of the design which seems to elude to many people writing about it, at high AoA, the boundary later sticks to this part of the fuselage when that of conventional designs have already vacated, not the case of Close-coupled canards, no need to consult in forum but to read studies about the formula from people who knows, like NASA/DRYDEN/Dassault/SAAB, interpretation if forum is much too often tainted and inaccurate.
                                        and people in the know such as the one work at SAAB don't claim PSM for Gripen, neither does Dassault themselves ever claimed Rafale capable of performing pedal turn or Kulbit or Herbst, enough said.
                                        The only thing you actually know is close coupled canard keep vortex from break down later than a pure delta, but that it, you have no numerical data to compare the side force that a close coupled canard such as Gripen can generate at high AoA such as 50 degrees to compare to twin tail aircraft such as F-35 or F-22 at the same exact condition. You have no data to evaluate how accurate their control can be or how fast the yaw can be initiated or stop
                                        In other words, your "analyze" base on very small amount of generic information all the while making very big claim and ignore dozens other related factors, it is like someone who say higher sweep wing has less drag, therefore, Mirage III must fly faster than Mig-25.


                                        Originally posted by ThincanKiller View Post
                                        There is NO "effet bote meuh" there, NO aerodynamic limitation if this is what this B.S means to some, quite the opposite, if you mistake acceleration with roll rate, as explained hundred of time by people who served in A-F using them, limitations are there to allow for your average squadron pilot to keep the A-C under control at all speed, since there is no speed limiter for example, and btw, the Mirage 2000 is also limited this way, even more in G than a Rafale
                                        btw, on F-18/F-35. vortexes breakdown in the area is also well documented (fluter/structural issues caused by aerodynamic bashing), so whatever AoA they will reach, they will not be as efficient as that of a close-coupled canard, even with the use of 2 vertical fins.

                                        So you guys can keep the effet bote meuh for confetis to throw at weddings because it's what it's worse, bar if you want to keep flaming French posters in forums.
                                        Another claim with no data to back up.
                                        FYI, posting that photo of F-35 in the wind tunnel with vortex hitting its tail (like you always do in other forums) doesn't prove your point, because:
                                        a- You don't have the same tunnel data for either Gripen or Rafale
                                        b- You don't have such data at all AoA, there is no chart or overlap curve showing their relative controllability at all AoA, it is nothing more than speculation in your part.
                                        c- F-18/F-35 can perform post stall maneuvers, and had demonstrated such ability, none ever seen from Gripen or Rafale.



                                        Originally posted by ThincanKiller View Post
                                        You don't need 30/40/50* AoA to do a pedal turn, all you need is low speed, at whatever AoA your A-C will allow you to pass the maneuver, so if you have the choice between transcient performances (energy/acceleration) and AoA which will take it all away from you, and become more of a limiting factor than an advantage, limiting the A-C AoA makes perfect sense.
                                        Conclusions of PSM tests were the same than those reached by X-31 pilots with on top the comment made by Yves Kerherve; "we don't need TVC".
                                        .Their comment was never that post stall maneuver is useless, but rather that it is not worth it to trade of important characteristic, such as acceleration or speed just to get PSM, that mean for example: it is not worth it to have post stall maneuver if in the process you decrease acceleration by 20% due to the added weight from TVC. On the other hand, having post stall maneuver capability while not having to trade other fighter characteristic or the loss is small, it is really worth it, since it can very useful in certain case and for that reason, many new aircraft still designed to have post stall capability such as Su-57, Su-35, F-35, F-18, F-22
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                                        Originally posted by ThincanKiller View Post
                                        Actually, bar going over 29/30* AoA, yes they can, because you don't need to get into a stall to do a pedal turn, you can do it in a stall though
                                        If it is such an easy task, why you still unable to find any video of either Rafale or Gripen perform the pedal turn?



                                        Originally posted by ThincanKiller View Post
                                        And even more efficiently, as demonstrated by Gripen maximum yaw rate in yaw spin tests, 30*/sec is a huge difference when it comes to 60* to 90*, but there is little advantage in ACM there
                                        High yaw rate in departure test offer no advantage to operational ACM, because in controlled departure, aircraft don't have the same level of control to get a fire solution like in a combat post stall maneuver. Beside, max yaw rate accumulated after several spins can't be used in combat either

                                        Originally posted by ThincanKiller View Post
                                        Take this a step further and this is precisely how you depart an A-C asymmetrically (as demonstrated by the descriptive of the yaw spin test on Gripen), start a yaw spin and stop it, you'll also need to recover speed, meaning using pitch, and all of this at AoA much lower than that reached by F-18/35.
                                        F-35 departure test was done at 110 deg AoA, i am quite Gripen don't go much further than that.

                                        Originally posted by ThincanKiller View Post
                                        close-coupled canards allows for lower AoA for the same amount of vortex lift (appears earlier in the AoA scale), therefore, higher lift/drag coefficient.
                                        Compare to a pure delta, yes.
                                        Other kinds of wing? not necessary, after all, delta is a kind of very high sweep wing.
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                                        Last edited by garryA; 3rd March 2019, 18:25.

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                                        • ThincanKiller
                                          Registered User
                                          • Feb 2019
                                          • 91

                                          Originally posted by garryA View Post

                                          F-35 departure test was done at 110 deg AoA, i am quite Gripen don't go much further than that.
                                          You're so full of it you still can't read plain English. ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ZZZZ...

                                          NOPE. 110% was the maximum AoA, the aircraft departed FAR earlier than that, but since you still can't comprehend the meaning of the words you copy/paste, we still have to suffer B.S by the bucket.

                                          And something else, the closest to 90*AoA the highest your yaw spin rotation rate can be ("helicopter" effect of the ailerons used to start/stop the spin during Gripen test didn't hit a brain cell either), 70/80* or 110* wouldn't explain the difference between the two, Gripen spanks F-35 demonstratively by 30*/sec and that's only due to a higher level of control authority.



                                          Stop writing in Aviation forums, take on knitting.
                                          Last edited by ThincanKiller; 3rd March 2019, 19:02.

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