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  • garryA
    Rank 5 Registered User
    • Dec 2015
    • 1120

    Originally posted by TooCool_12f View Post

    on the other hand, if their FCS is programmed to remain capped at 28-29, it's not supposed to get there in the first place, no? There was an interview of the Rafale chief test pilot Yves Kerherv who explained that, during development, for spin testing they had to disable a number of fcs features to have it in a pretty much "direct mode" (no automatic recovery of anything of the sorts) as the aircraft simply wouldn't depart into a spin regardless of what the pilot did, and what's more, even when they finally managed to get it into a spin, all they had to do was to release stick and rudder, and the aircraft would recover itself aerodynamically (with no input either from the pilot nor the fcs - as the fcs was in that "direct mode")

    So, basically, if they have made a choice not to go into post stall manoeuvering and programmed the FCS that way, how would you see the Rafale doing any post stall manoeuvers?
    My point is:
    _ Most fighters are put in spin recovery / departure test, but able to recover from a spin, highly spin resistant doesn't mean they have control authority to ultilize post stall maneuver in combat. Because PSM for combat also require high level of accuracy for the pitch/ yaw rate, as well as the ability to start / stop quickly
    _ thincankiller claimed the pedal/helicopter turn is not a post stall maneuver, and Rafale had done the same thing, so the homework is simple: where is the video?

    Comment

    • TooCool_12f
      Rank 5 Registered User
      • Dec 2009
      • 3316

      Originally posted by garryA View Post

      My point is:
      _ Most fighters are put in spin recovery / departure test, but able to recover from a spin, highly spin resistant doesn't mean they have control authority to ultilize post stall maneuver in combat. Because PSM for combat also require high level of accuracy for the pitch/ yaw rate, as well as the ability to start / stop quickly
      _ thincankiller claimed the pedal/helicopter turn is not a post stall maneuver, and Rafale had done the same thing, so the homework is simple: where is the video?
      well, not "most fighters" but "all fighters" have to pass those tests, as in combat, you never know what the pilot will have to do and if he won't find himself in a spin at a moment.. so these tests are mandatory to validate the behavior of the new aircraft under such circumstances... as I pointed out above, the chief test pilot explained that they were unable to get the Rafale into a spin no matter what they did to it, and to be able to perform the spin test, they had to deactivate most if not all protections of the FCS. Once they've done it, they validated it had positive behavior and was safe.. and then went on... as they've concluded that they don't need PSM, the FCS was programmed that way.. so you won't ever see a Rafale perform such manoeuvers, simply because the FCS will keep it under a flight rules it was programmed to maintain

      and you won't find a video of Rafale spin tests, if anything, because the french didn't film all the flight tests and those they have are most certainly kept confidential.. which is the french policy dating from decades (an example of that policy was seen about 15 years ago when some developers were working on Falklands air war.. they could get all the information needed for the Harrier modelling, but when it came to the MIrage III (we were in the early 2000's, remember), they asked to french sources but couldn't get any useful information because it was still classified (in France, the Mirage III had been retired some 20 years ago at the time).. they had to work with Argentina

      Comment

      • garryA
        Rank 5 Registered User
        • Dec 2015
        • 1120

        Originally posted by TooCool_12f View Post

        well, not "most fighters" but "all fighters" have to pass those tests, as in combat, you never know what the pilot will have to do and if he won't find himself in a spin at a moment.. so these tests are mandatory to validate the behavior of the new aircraft under such circumstances... as I pointed out above, the chief test pilot explained that they were unable to get the Rafale into a spin no matter what they did to it, and to be able to perform the spin test, they had to deactivate most if not all protections of the FCS. Once they've done it, they validated it had positive behavior and was safe.. and then went on... as they've concluded that they don't need PSM, the FCS was programmed that way.. so you won't ever see a Rafale perform such manoeuvers, simply because the FCS will keep it under a flight rules iton
        I said most because i wasn't sure if legacy fighter such as Mig-21, P-47 were also put under such test.
        and i never deny that Rafale can recover from a spin or that it is extremely spin resistant, i only disagreed with tincankiller claim that Rafale can and had done the same post stall maneuver as F-35
        F-35 is also very departure resistance
        Click image for larger version  Name:	3F72811F-1B5A-437E-9951-2EA436573F0F.png Views:	0 Size:	27.1 KB ID:	3852730
        Last edited by garryA; 24th February 2019, 09:39.

        Comment

        • ThincanKiller
          Registered User
          • Feb 2019
          • 91

          Originally posted by garryA View Post
          I love how you keep changing the criteria for PSM in the face of new evidences:


          Yet you can't find a single video of Rafale and Gripen perform a post stall maneuver. What a coincident
          1) You didn't provide any "new evidences" and I didn't change anything, from the moment members of L-M flight test team mentioned loss of control and the reasons for their test, your "new evidences" were moot, sorry.

          2) You still fail to demonstrate PS Maneuvers testing phases by L-M flight test members simply because they do not mention them, quiet the opposite.


          Title of the video:

          F-35 Test Pilot Dave Nelson talks about intentional departure and recovering from stalls during F-35A high angle of attack testing at Edwards Air Force Base, Calif. Flight Test Engineer Lea Haubelt explains how the tests help define the F-35 flight control software.
          Lea Haubelt explains how the tests help define the F-35 flight control software:

          To make sure the A-C stays within those parameters, not to allow for PSM.

          All you demonstrated is: You don't know what post stall maneuvers are, read the definition of the word maneuvers first.

          You ignore FACTS such as, the mention of loss of control vortex breakdown, F-22 being better at it (but they still never use PSM in combat), ALL A-Cs in this field go through the same flight testing phases and use the same "manoeuvrability" capabilities with the SAME control surfaces to get out of yaw spins, test includes increasing yaw rates and oscillations with use of some control surfaces, so according to your fuzzy definition, a Jaguar is capable of PSM.


          Quote Dan Canin F-35 test pilot:


          There are several different phonomenon that occur when you get high Angle of attack.

          First of all, as the angle of attack increases, the flow which is normally very smooth, starts to separate from the surfaces and you got a lot of turbulences.

          First we had the basic controlability problem of high angle of attack, and flow separation also the challenge of having relatively low dynamic pressures.

          You put the A-C into a spin,
          you get the A-C established into that out of control condition, and then when the controller calls, we add a lot to that condition.




          = High AoA and spin recovery procedures and nothing 3rd and 4th gen A-C did not do:

          Mention of airflow separation, vortex breakdown AND loss of control at high AoA.


          Intentional Departure

          CF-5 Flight Test Engineer Taurean Williams.

          We're testing to see if the aircraft is still controllable at the high angle of attack regime.

          Once we are able to charecterize the characteristics of the aircraft at that high angle of attack regime, we move to intentional departure.


          NOT a mention of full 3-axis control authorify during the maneuver and even less of PSM.
          Apparently the only thing that matters to you is air shows commercial B.S, understandably since you have no clue what high AoA and spin flight test procedures are, even the simplest basics of stall recovery or else you'd have pick it up.

          Regardless of the FACT that L-M are pushing all out to sale their A-C and naturally have changed the goal posts you mentions, not me, flight test procedures remains the same, reasons for testing as well and in the case of the F-35 it is not PS maneuvers testing but what they say, L-M pilots on the payroll of L-M taking people for fool at airshow don't sale it. You get it?

          Now, what speed would a Rafale be PSM?10 kt?

          Does Gripen yaw 30* faster than F-35 in the same situation? Yep. That's controllability levels for you, when L-M test pilot mentions loss of control, a Gripen yaws 30*/sec FASTER that F-35.

          Now as I mentioned already Rafale pilots don't need a relaxed FCS to put an A-C at 50* AoA in order to achieve PSM and the reason why it is limited is well known, they tested PSM and concluded the SAME than DRYDEN X-31 pilots, you loose more qualities than you gain in combat by using them, reason why F-22 pilots wisely do not.

          Keep spamming and flooding this topic with stuff you still haven't understood, it's amusing.

          Comment

          • TooCool_12f
            Rank 5 Registered User
            • Dec 2009
            • 3316

            garryA

            Rafale, except maybe during some test flights obviously doesn't do such manoeuvers.. . As for spin testing, it was soon after the end of WWI that it became "standard"..

            You can read about "spin history" in UK here:

            https://www.aerosociety.com/media/48...-uk-part-1.pdf

            and page 7 you can read:

            "The Air Ministry also had overall responsibility for theAeroplane and Armament Experimental Establishment (A&AEE), which was located at Martlesham Heath in Suffolk in 1924. Its antecedents had been the former Aircraft Testing Flight of the Central Flying School at Upavon, which had moved to Martlesham in 1917, and the Armament Flight that had moved to nearby Orfordness. Its function was to evaluate aircraft that were being considered for potential entry into service with the RAF. (A similar function was performed for naval aircraft at the neighbouring Marine Aircraft Experimental Establishment (MAEE), which moved to Felixstowe in 1924.) From about 1918, spinning and spin recovery were among the characteristics to be investigated as a matter of routine."

            thanks for raising the point, got me an interesting read now

            so, you can take for granted that all post 1920 designs had to pass spin tests prior to entering service
            Last edited by TooCool_12f; 24th February 2019, 10:52.

            Comment

            • ThincanKiller
              Registered User
              • Feb 2019
              • 91

              Originally posted by garryA View Post
              I said most because i wasn't sure if legacy fighter such as Mig-21, P-47 were also put under such test.
              and i never deny that Rafale can recover from a spin or that it is extremely spin resistant, i only disagreed with tincankiller claim that Rafale can and had done the same post stall maneuver as F-35
              F-35 is also very departure resistance
              Click image for larger version Name:	3F72811F-1B5A-437E-9951-2EA436573F0F.png Views:	0 Size:	27.1 KB ID:	3852730
              You said a lot of things because you simply don't know your very basics:

              Example: The way you interpret this bit is FUNNY.

              1) Where did they mention turning this FCS off?

              Never, meaning the FCS needed to be twicked because otherwise it would prevent departure which is not exceptional for a FCS since it is designed for the purpose of keeping the A-C within its controlled flight parameters, it doesn't mean that the aerodynamic of the A-C make it spin-resistant, there is NO mention there of the aerodynamics preventing departure on its own, but FCS is mentioned and it was not turned off.

              2) Cg range and out of Cg range tests are ALSO part of the procedures, again nothing unusual there, apart for you.


              Another example: What one trainee pilot will learn even before flaring an A-C and landing, stall characteristics and the importance of speed recovery, speed recovery procedure, which control surface works and up to which AoA on your A-C, when their role crosses (rudder instead of ailerons), not to use ailerons in the stall as not to increase loss of control by stalling one wing further which would trigger a spin.

              ALL OF WHICH allows you to mistake high AoA for PSM, take those basics a step higher, you end up triggering spins, increasing the yaw rate, stopping the spin using the same controls as Boston Combe did with a Jaguar in yaw spins at 100* AoA, NO PSM there.

              Simple, but too high end for you.

              Forget P-47, you posted videos or articles of F-14 and F-16 departures as "evidences", regardless of the fact that their characteristics at high AoA were more than average, especially the F-14 and in the case of assymetric load, F-16, which is AoA limited also because your average squadron jockey might not be able to get out of a superstall, in fact you have NO clue what the difference between departed and controlled flight are.

              If we had been able to find any video of Gripen and Rafale flight tests and PSM test phases you wouldn't have been able to pick up on the most important aspect of the tests, controllability, so naturally meaning of the word maneuver is unknown to you.

              WHY does a Gripen out-perform the F-35 in a (fully controlled on 3 axis from the start of the maneuver) 70/80* AoA yaw spin by 30*/s and still can get out of it if it is not what U. Clarus says of it?

              HOW can a Rafale pilot practise (that the word used, not "reached") speeds as low as 15kt in mock combat vs a Mirange 2000 before high AoA testing and go away with it, was it NOT PSM?

              So I reiterate: There is no video, but we know more than a few things:

              1) ONERA CG-simulated PSM, Test flight team evaluated them and the conclusion of the tests are the SAME than that of the test pilots of X-31 program which was specifically designed for exploring PSM.

              You read well, (I magnified it to make sure because I have doubts about your eyesight after all the little "details" you missed):

              The pilots in the program did not support trading off other important fighter characteristics just to acquire the EFM capabilities the X-31 possessed.

              Click image for larger version  Name:	X-31-conclusion.jpg Views:	0 Size:	155.7 KB ID:	3852740

              I said this even before posting this X-31 evidence, explained several time over WHY AdlA/M.N chose to limit the Rafale at 29* and in the roll axis as well, WHY they never considered TVC ("we don't need TVC" dixit Yves Kerherve chief test pilot for the Rafale development program).

              But nope, you keep posting, spamming, flooding this topic with PSM irrelevant stuff because some geezer is doing his commercial job at an airshow, sales you high AoA maneuvers for "exceptional" PSM capabilities and you FAIL to pick up on all of that?

              LOL! Don't ask us to fall for it as easily as you do, please, I guaranty you that many of us knows better.
              Last edited by ThincanKiller; 24th February 2019, 11:42.

              Comment

              • ThincanKiller
                Registered User
                • Feb 2019
                • 91

                Originally posted by TooCool_12f View Post
                garryA

                Rafale, except maybe during some test flights obviously doesn't do such manoeuvers.. . As for spin testing, it was soon after the end of WWI that it became "standard"..
                ONERA mentioned this in one of their CG-simulation topics, I can't find it (as is the case for many documentation) since their web site have changed since.



                Originally posted by TooCool_12f View Post
                You can read about "spin history" in UK here:

                https://www.aerosociety.com/media/48...-uk-part-1.pdf

                and page 7 you can read:

                "The Air Ministry also had overall responsibility for theAeroplane and Armament Experimental Establishment (A&AEE), which was located at Martlesham Heath in Suffolk in 1924. Its antecedents had been the former Aircraft Testing Flight of the Central Flying School at Upavon, which had moved to Martlesham in 1917, and the Armament Flight that had moved to nearby Orfordness. Its function was to evaluate aircraft that were being considered for potential entry into service with the RAF. (A similar function was performed for naval aircraft at the neighbouring Marine Aircraft Experimental Establishment (MAEE), which moved to Felixstowe in 1924.) From about 1918, spinning and spin recovery were among the characteristics to be investigated as a matter of routine."

                thanks for raising the point, got me an interesting read now

                so, you can take for granted that all post 1920 designs had to pass spin tests prior to entering service
                Yeah, good one and certainly high AoA post stall as well, I wonder if they were doing PSM in 1920?

                Says a lot about the technico-commercial role of some pilots and the B.S that can be said during air shows.



                Originally posted by TooCool_12f View Post
                well, not "most fighters" but "all fighters" have to pass those tests, as in combat, you never know what the pilot will have to do and if he won't find himself in a spin at a moment.. so these tests are mandatory to validate the behavior of the new aircraft under such circumstances... as I pointed out above, the chief test pilot explained that they were unable to get the Rafale into a spin no matter what they did to it, and to be able to perform the spin test, they had to deactivate most if not all protections of the FCS. Once they've done it, they validated it had positive behavior and was safe.. and then went on... as they've concluded that they don't need PSM, the FCS was programmed that way.. so you won't ever see a Rafale perform such manoeuvers, simply because the FCS will keep it under a flight rules it was programmed to maintain
                and you won't find a video of Rafale spin tests, if anything, because the french didn't film all the flight tests and those they have are most certainly kept confidential.. which is the french policy dating from decades (an example of that policy was seen about 15 years ago when some developers were working on Falklands air war.. they could get all the information needed for the Harrier modelling, but when it came to the MIrage III (we were in the early 2000's, remember), they asked to french sources but couldn't get any useful information because it was still classified (in France, the Mirage III had been retired some 20 years ago at the time).. they had to work with Argentina


                Agreed on most point except for one detail, they did film ALL Rafale test flight (procedure), only those footages are not going to be made public before a long time, the amount of material we are entitled to see is very limited, best example; details (client only) on Rafale supercruise capabilities "leaked" during a Paris airshow some years ago, it did trigger the sort of reaction from the Anglo-American fighter mafia naturally, since the S-C performaces of the competition (E-F Typhoon) didn't look so "superior" after all and Rafale O_0 ooooch could supercrusie with. AAMs and one external tank. What do we know?



                Very much the same for the ATLC Rafale vs F-22 video, if it hadn't been "leaked" we would have had to content with the same mafia constant bashing in Rafale topics.
                Last edited by ThincanKiller; 24th February 2019, 11:37.

                Comment

                • TooCool_12f
                  Rank 5 Registered User
                  • Dec 2009
                  • 3316

                  Originally posted by ThincanKiller View Post
                  HOW can a Rafale pilot practise (that the word used, not "reached") speeds as low as 15kt in mock combat vs a Mirange 2000 before high AoA testing and go away with it, was it NOT PSM?
                  .
                  won't go through all your stuff (way too boring and pointless), but just for your information: 15kt doesn't imply that it was stalled at any point, besides the fact that the FCS wouldn't allow it to stall anyway.. which means it had no need for PSM... stall is a matter on AoA and airflow not following the upper surface of the wings, not speed

                  Comment

                  • Scorpion82
                    Rank 5 Registered User
                    • Jul 2005
                    • 4474

                    I thought monsieur Sampaix's troll time was over. Bit he is back and does what he has been doing for the past 15 years or so, flooding forums, derailling threads and prenzending to be the one and only person with a clue about aviation. I can only advise not to feed the troll this only charges his troll batteries and motivates him to become even more aggressive. Hope there are still dome mods who will put an end to this, rather sooner than later. Otherwise we'll see another months long troll attack which will surpress any other discussions.

                    as said don't feed the troll!!!

                    Comment

                    • ThincanKiller
                      Registered User
                      • Feb 2019
                      • 91

                      Originally posted by TooCool_12f View Post

                      won't go through all your stuff (way too boring and pointless), but just for your information: 15kt doesn't imply that it was stalled at any point, besides the fact that the FCS wouldn't allow it to stall anyway.. which means it had no need for PSM... stall is a matter on AoA and airflow not following the upper surface of the wings, not speed
                      Originally posted by TooCool_12f View Post
                      on the other hand, if their FCS is programmed to remain capped at 28-29, it's not supposed to get there in the first place, no? There was an interview of the Rafale chief test pilot Yves Kerherv who explained that, during development, for spin testing they had to disable a number of fcs features to have it in a pretty much "direct mode" (no automatic recovery of anything of the sorts) as the aircraft simply wouldn't depart into a spin regardless of what the pilot did, and what's more, even when they finally managed to get it into a spin, all they had to do was to release stick and rudder, and the aircraft would recover itself aerodynamically (with no input either from the pilot nor the fcs - as the fcs was in that "direct mode")
                      So, basically, if they have made a choice not to go into post stall manoeuvering and programmed the FCS that way, how would you see the Rafale doing any post stall manoeuvers?
                      PSM were achieved the moment they flew the A-C at 15kt unless you take Rafale for a Cihense kite, it is pretty obvious that practising mock combat maneuvers and getting it at speeds as low as 15kt is out of the A-C flight envelop.
                      Last edited by ThincanKiller; 24th February 2019, 11:57.

                      Comment

                      • ThincanKiller
                        Registered User
                        • Feb 2019
                        • 91

                        Originally posted by Scorpion82 View Post
                        I thought monsieur Sampaix's troll time was over. Bit he is back and does what he has been doing for the past 15 years or so, flooding forums, derailling threads and prenzending to be the one and only person with a clue about aviation. I can only advise not to feed the troll this only charges his troll batteries and motivates him to become even more aggressive. Hope there are still dome mods who will put an end to this, rather sooner than later. Otherwise we'll see another months long troll attack which will surpress any other discussions.

                        as said don't feed the troll!!!
                        O_0 oooch.

                        Another acute paranoia sufferer, after Picard, now this guy, do you have any other to name, one of those who demonstratively demolished your "Rafale" and aerodynamic "expertise"?

                        I visited an Indian forum once, aren't you the geezer who tried to pass himself for a German Air Force mechanic and pretended that E-F canards were used in the roll axis once?

                        I know German engineering is supposed to be top but you got me hurting with laugher there.

                        Have a good day sir.

                        Comment

                        • TooCool_12f
                          Rank 5 Registered User
                          • Dec 2009
                          • 3316

                          Originally posted by ThincanKiller View Post



                          PSM were achieved the moment they flew the A-C at 15kt unless you take Rafale for a Cihense Kite, it is pretty obvious that practising mock combat maneuvers and getting it at speeds as low as 15kt is out of the A-C flight envelop.
                          which is a nice demonstration of your ignorance.. now you can go back to school and learn a bit... or not...

                          Comment

                          • ThincanKiller
                            Registered User
                            • Feb 2019
                            • 91

                            Originally posted by TooCool_12f View Post

                            which is a nice demonstration of your ignorance.. now you can go back to school and learn a bit... or not...
                            Originally posted by TooCool_12f View Post
                            won't go through all your stuff (way too boring and pointless), but just for your information: 15kt doesn't imply that it was stalled at any point, besides the fact that the FCS wouldn't allow it to stall anyway.. which means it had no need for PSM... stall is a matter on AoA and airflow not following the upper surface of the wings, not speed






                            Yes it does, for one thing I certainly don't ignore is the relationship between airflow speed and lift, no speed, no lift, simple enough, read the definition of a stall and 15kt is way to low for the airflow to stay on the wing surface, even with FCS limiting it to 30* AoA, (not 29* at the time but 30), you already departed, whatever the A-C attitude, you don't have enough of it to stay airborn.

                            Another detail, they never said they couldn't stall it, they said they couldn't get it into a superstall, which is different, it is a characteristic of Delta Canards, the boring stuff gives you links to Gripen tests and those are explained in detail.

                            The fact that they conducted spin trials is the proof of it, they needed to stall it first, passively (speed) or dynamically (AoA), passive stall is the equivalent of flaring during landing, if you do it 1000ft above the runway, it won't matter a bit, it still will stall.
                            Feel free to elaborate instead of emulating the flamers, because this is the precise reason why the French community get bashed up, and coming up with inaccuracies such as this one doesn't help.
                            Last edited by ThincanKiller; 24th February 2019, 12:15.

                            Comment

                            • TooCool_12f
                              Rank 5 Registered User
                              • Dec 2009
                              • 3316

                              Originally posted by ThincanKiller View Post



                              Yes it does, for one thing I certainly don't ignore is the relationship between airflow speed and lift, no speed, no lift, simple enough, read the definition of a stall.
                              so you don't know what you pretend to speak about... bye

                              Comment

                              • ThincanKiller
                                Registered User
                                • Feb 2019
                                • 91

                                Originally posted by TooCool_12f View Post

                                so you don't know what you pretend to speak about... bye
                                Say you, pretending that a Rafale cannot stall when in fact they need to stall it not only for spin tests but also landing (that's what it is, flare is a controlled stall) take some doing, do you really think the airflow is still there to provide enough lift at 30* AoA and 15kt?

                                What makes you recover from a stall? SPEED. When you run out of speed, you simply don't have enough lift left and that's a stall.

                                Chinese Kite stories.

                                Good vacation then, but a bit of advise, stop posting stuff such as "can't stall a Rafale" instead of can't put it in a superstall because it is resistant to it, it doesn't serve French forumers credibility.
                                Last edited by ThincanKiller; 24th February 2019, 12:40.

                                Comment

                                • TooCool_12f
                                  Rank 5 Registered User
                                  • Dec 2009
                                  • 3316

                                  so you have zero clue actually.. you remind me of a fellow we had with us in high school.. he "loooooved" mathematics and used all sorts for formulae you don't learn before college... his only problem, he had no clue how to use them properly and his results were consistently very poor... we used to joke about him saying that he loved mathematics but unfortunately the mathematics didn't love him... same for you and aerodynamics, obviously

                                  now a little question for you:

                                  I take my kid for a flight here and there, and he always asks me to do some "rollercoasters" (his name for that manoeuver), my plane is a DR400-120, so no aerobatics, heavy G, inverted flight and so on.. stall speed level is about 50kts. During the manoeuver, we get at moments down to 40, the ground somewhere way to one side and yet, the aircraft isn't stalled.. it isn't even close (and no stall warning horn, no buffet, nothing...)

                                  what type of manoeuver allows it? if you find, you may understand why the Rafale was never stalled @15kts and didn't need to be

                                  Comment

                                  • ThincanKiller
                                    Registered User
                                    • Feb 2019
                                    • 91

                                    Originally posted by TooCool_12f View Post
                                    so you have zero clue actually.. you remind me of a fellow we had with us in high school.. he "loooooved" mathematics and used all sorts for formulae you don't learn before college... his only problem, he had no clue how to use them properly and his results were consistently very poor... we used to joke about him saying that he loved mathematics but unfortunately the mathematics didn't love him... same for you and aerodynamics, obviously

                                    now a little question for you:

                                    I take my kid for a flight here and there, and he always asks me to do some "rollercoasters" (his name for that manoeuver), my plane is a DR400-120, so no aerobatics, heavy G, inverted flight and so on.. stall speed level is about 50kts. During the manoeuver, we get at moments down to 40, the ground somewhere way to one side and yet, the aircraft isn't stalled.. it isn't even close (and no stall warning horn, no buffet, nothing...)

                                    what type of manoeuver allows it? if you find, you may understand why the Rafale was never stalled @15kts and didn't need to be
                                    Really? So Picard, Sampaix, now another geezer, you guys keep on with this character bashing, it's funny, I don't need your expertise in aerodynamics to know that you perfectly can stall a Rafale, enough with forum legends, and I did read the full Flight test report when it was still available and not the truncated version of it among other documents on the A-C.

                                    Try a renversement, your kids will love it: Pull up vertical, wait for your anemometer to crash, when the AC give you a good buffet, Rechaufe Carbu (on your A-C), idle gas to kill your speed and when you feel the A-C is about to go down, full gas with rudder in the propeller rotation to help it yaw until you are nose down, then keep full throttle, off Rechauffe Carbu up to the speed which allows your A-C for recovery.
                                    Here you go, you just experienced a PSM.




                                    Did I mention Speed again?

                                    To summarize; It matters little how much of airflow remains on Rafale wing at 30* AoA and 15kt, part of it already departed the surface despite the very good low/speed high AoA airflow characteristics provided by the canard surfaces, as I said, it is not a Chinese Kite, (and at 10 tons +, no DR400-120 either) and the result is that you do not have enough lift left to stay airborne, stall is characterized by loss of lift to this point, AoA or speed or both.

                                    There are a few ways to stall an A-C, this is just one of them, sure it still had 3 axis control but the A-C was out of its flight parameters and the definition of flight means enough lift to stay up, nothing else, so at 15kt/30* AoA it was PSM.

                                    ps if you haven't practised the maneuver I described during your training, first do it with an instructor, or your kids wont enjoy the results that much.
                                    Last edited by ThincanKiller; 24th February 2019, 13:15.

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                                    • TooCool_12f
                                      Rank 5 Registered User
                                      • Dec 2009
                                      • 3316

                                      renversement (hammerhead) is an aerobatic manoeuver (so it's not the one I do), and once more you come at "30/15kts -> departed... wrong...

                                      come on, keep displaying your nonsense
                                      Last edited by TooCool_12f; 24th February 2019, 13:19.

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                                      • ThincanKiller
                                        Registered User
                                        • Feb 2019
                                        • 91

                                        Originally posted by TooCool_12f View Post
                                        renversement (hammerhead) is an aerobatic manoeuver (so it's not the one I do), and once more you come at "30/15kts -> departed... wrong...

                                        come on, keep displaying your nonsense
                                        So your aerodynamic expertise doesn't extend to PSM or renversement then? Damned what do they teach newbies at flying schools those days, I did it hundred of times, flew MS-880-100 cv backward in high AoA attitude with just enough speed to let the wind push us back in relation to a point on the ground to demonstrate this, done some limited acro too in the 100 sport etc etc.

                                        I said: Airflow departed the wing surface to an amount high enough to prevent the attitude to be called flight, that's what I meant by departed.

                                        As for Rafale pilots, they never said "can't stall it", which you recognised by pretending that there was only one maneuver which would allow for it, but "can't put it in a superstall", because the A-C is fully aerodynamically stall resistant and even if you could force it into one superstall, its control authorithy remains high enough to get out of it, you really should have a look at this U. Clarus report on the Gripen, it gives good clues as to why the close-coupled canard delta have such characteristics..

                                        The simplified definition of stall which mentions only AoA as a cause is incomplete, or else, speed wouldn't be such an important recovery factor, so speed matters just as much as AoA when it comes to loss of lift (regadless of the amount of airflow remaining on the wing surface), a "purist" or newbie will always see it as in AoA/low speed situation in level flight, obviously it is limited to one way to stall an A-C.

                                        In short, in an attitude where your AoA is zero but your speed too low to provide lift, as for the case of a renversement, you are already PS, so you can keep thinking 15kt provide enough of it to keep level flight on a 10t + fighter, I reiterate that it is not the case and that at this point you already are in a stall situation.

                                        Furthermore, it is much unlikely that the maneuver was done on the horizontal plan, I do not have the details of those mock combats but I can guaranty you that the pilot didn't try to slow down the A-C on the horizontal plan by putting the engine in idle, use A-F function, keep it level while increasing AoA and wait for the speed to crash, he most probably did it during a defensive or offensive yo-yo in the vertical plan, with full control authority for the speed (sluggish but still there) much closer to the renversement maneuver situation.

                                        So yes, you can stall a Rafale at 15kt.

                                        I suddenly came to ask myself a question, is the structural load factor of Rafale high enough to pass a renversement using rudder at a speed where it would still rotate the A-C 180* while vertical?

                                        Good question eh? Because there is no TVC or propeller torque to help pass the hammerhead maneuver on this jet, in theory it should be possible, depending on this Structural load factor...
                                        Last edited by ThincanKiller; 24th February 2019, 14:08.

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                                        • TooCool_12f
                                          Rank 5 Registered User
                                          • Dec 2009
                                          • 3316

                                          Originally posted by ThincanKiller View Post

                                          So your aerodynamic expertise doesn't extend to PSM or renversement then? Damned what do they teach newbies at flying schools those days, I did it hundred of times, flew MS-880-100 cv backward in high AoA attitude with just enough speed to let the wind push us back in relation to a point on the ground to demonstrate this, done some limited acro too in the 100 sport etc etc.
                                          blah blah blah.. your mom never taught you that it's not nice to lie? had your done it "hundreds of times" you'd know that speed as such is irrelevant as far as stall is concerned... and I still wait for that manoeuver that I routinely can do with my DR400.. as a pilot, you should have no trouble knowing what I speak about... so?

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