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  • From reading Sport Copter's website, I don't get the impression that gyro loops and rolls are being "promoted".
    Rather, such seem to me a photographic expression of how well-built are their gyros.

    In fact, the only time loops and rolls are even mentioned, is here:

    Jim wrote the parameters and guidelines for gyroplane looping for the FAA in 1998 after performing the world’s first loop in a conventional gyroplane (1997). He is the only gyro pilot in the world that holds an ICAS (International Council of Air Shows) card for gyroplane looping and rolling. He also holds the “Statement of Acrobatic Competency” card, from the FAA, which authorizes him to perform aerobatics, “to loop and roll consecutively” and “in formation”, in a Sport Copter gyroplane.


    There are many superb gyro pilots out there, and I haven't heard of even them trying loops and rolls in their respective machines.
    I doubt anybody less skilled would have the balls to try it.
    So, I don't think beginners are being tempted to do so.
    PP - ASEL complex (C172RG, Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, Sport Copter II, M912), soloed in gliders

    "
    When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

    Comment


    • Phil, people have been looping gyroplanes since 1932, back when Johnny Miller used to do it routinely at airshows in his Pticairn PCA-2 (the same Miller who flew off the Philadelphia Post Office roof with airmail service). He had plenty of acro experience before trying it, and built up thousands of hours in the Pitcairn, and was certainly not a novice from any standpoint. If you don't have significant acro experience, it is probably foolhardy to experiment.

      The management of g-load is critical to survival. Conventional airplane/glider inside loops are done with high g at the bottom and low to zero g at the top, to produce a nice round shape that IAC judges like. Direct control rotorcraft generally won't do that shape without a rigid rotor system. To maintain positive g, the shape becomes more like a long-hand script lower case "e". Watch this old film of Harold Thompson in the Sikorsky S-52 and you'll see what I mean about the shape:

      https://youtu.be/xhRUGKa_ImY

      I never tried it in my old S-52, being content to keep it right-side up and let Thompson keep all the glory.

      The Red Bull Bo-105 has the benefit of a hinge-less elastomeric hub design, and that gives more flexibility (pun intended) for its maneuvers (it does not complain at -1g); the German military have been doing all sorts of wild things in them since the 1970s.

      Barrel-rolling can be done in nearly anything (well, not so much in balloons) with positive g maintained.

      I suggest getting some vigorous fixed wing time to get the feel for what it takes to maintain g in a roll before experimenting rotor-borne. Aileron rolls and snaps rolls are not in the playbook for rotorcraft for obvious reasons -- you want to experience barrel rolls with an acro instructor on board in a fixed wing and feel out your comfort level before letting courage get the better of you.

      Comment


      • Yes the loops are pitched at the top and the rolls are barrelled - I guess as a consequence of the need to remain +g and energy. As you say they wouldn't score very well in competition aeros. So nothing technical in the Sportcopter design they just happen to have a pilot willing / able to fly the figures.

        Comment


        • people have been looping gyroplanes since 1932, back when Johnny Miller used to do it routinely at airshows in his Pticairn PCA-2 . . .
          WaspAir, was anybody before Jim Vanek in 1997 looping gimbal-head teetering blade gyros? Were you?


          So nothing technical in the Sportcopter design they just happen to have a pilot willing / able to fly the figures.
          Actually, Phil, there is much due to the Sport Copter design that permits the safe and repetitive ability of their machines to be flown aerobatically.
          Their controls, mast and rotor system are by far the most robust in the industry.

          Regards,
          Kolibri


          PP - ASEL complex (C172RG, Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, Sport Copter II, M912), soloed in gliders

          "
          When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

          Comment


          • So...we seem to be straying from S-turns and/or anything related to modifying the approach distance and/or landing unless loops or barrel rolls are to be considered, which I respectfully doubt . Would this be a good time to move what seems to be SportCopter-specific stuff to the SportCopter area? Just askin’...

            /Ed

            Comment


            • I've been trying to for several posts to reply and let the thread resume its former topic.
              PP - ASEL complex (C172RG, Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, Sport Copter II, M912), soloed in gliders

              "
              When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

              Comment


              • Originally posted by EdL View Post
                So...we seem to be straying from S-turns and/or anything related to modifying the approach distance and/or landing unless loops or barrel rolls are to be considered, which I respectfully doubt . Would this be a good time to move what seems to be SportCopter-specific stuff to the SportCopter area? Just askin’...

                /Ed
                Im sorry Ed apologies for the drift. S turns i sum up!! And at great risk of starting the debate!!!! I think those contributing know how to do them and safely i just dont see the argument being made that makes them more efficient than doing vertical descent. Which if you can do s turns well no reason you cant Vd well... anyway. Just to finish on looping... does it require good tevhnique or robust aircraft?? And.. can you do them 2 up?? And will he do them at Oshkosh?

                Comment


                • Kolibri, Phil

                  I didn’t mean to put a complete damper on the conversation and did say “we” rather than “you”.

                  There seemed to be a growing amount of SportCopter info and pictures alone and, for those interested in learning more about SCs, it may prove difficult to find the useful information on them shared in this thread if one is searching for PIREPS re their gyros.

                  As for the loops and barrel rolls, a quick search of “Jim Vanek” on YouTube brought up a video of him doing several of both. I must say, they can be DONE but neither appears glamorous. The barrel roll in particular looks like the gyro has been shot down. That’s not meant to be a reflection on the specific gyro - just what happens when one must maintain positive G.

                  As for S-turns, I’ve actually been out playing with them during the course of this thread. Personally I do think they have their place, albeit rarely (engine out and I must land right down THERE). Vertical descent is clearly the first and best option (and what I was taught) - when high enough to safely recover adequate forward speed. As discussed, that can be deep into the “traditional” H/V curve but it still takes a considerable, cheek-tightening amount of altitude to get from 20mph to a safer figure. And that’s by myself: with a passenger and on a hot Texas day, it will take even more. But if people root around below the top altitude of the typical H/V curve, which is where the fun really is, it’s good to have options you can exercise.

                  In any case, thanks for the different ideas and considerations. Overall, safely practicing and at least thinking through emergency procedures is a good idea - and can be fun, too.

                  /Ed

                  Comment


                  • I didn’t mean to put a complete damper on the conversation and did say “we” rather than “you”.
                    Thanks, EdL.

                    Just to finish on looping... does it require good tevhnique or robust aircraft?? And.. can you do them 2 up?? And will he do them at Oshkosh?
                    Phil, for repetitive looping, I'd say both. He told me that he wouldn't attempt it in any other gyro but his own product.
                    2-up: Yes, at least in the SCII.
                    No, not at Oshkosh 2019, but perhaps at Mentone if he exhibits there.

                    As far as gyro S-turns go, even if they're not often called for, I'm all for having as many skillset "tools in the toolbox".

                    Regards,
                    Kolibri
                    PP - ASEL complex (C172RG, Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, Sport Copter II, M912), soloed in gliders

                    "
                    When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

                    Comment


                    • Originally posted by Philbennett View Post
                      Just to finish on looping... can you do them 2 up??
                      On our shores, the regulations come into play then, specifically FAR 91.307(c). Because there is no second pilot required for any VFR gyro operation, the other seat occupant is "a person other than a crewmember", so ...

                      (c) Unless each occupant of the aircraft is wearing an approved parachute, no pilot of a civil aircraft carrying any person (other than a crewmember) may execute any intentional maneuver that exceeds -

                      (1) A bank of 60 degrees relative to the horizon; or

                      (2) A nose-up or nose-down attitude of 30 degrees relative to the horizon.


                      Interestingly, this regulation has never been changed to permit airframe ballistic recovery parachutes to suffice. One must wonder whether a BRS system could be expected to work in the unusual attitudes that can arise from a botched acro maneuver.

                      I've always found parachutes uncomfortable in any aircraft lacking seats specifically designed to accommodate them, and two 'chutes will also add noticeable weight, but those are relatively small issues in this higher-risk context.

                      The physics of the maneuver won't change, but the loading and performance obviously would.

                      Comment


                      • I'm pretty sure that I've read of successful BRS being used on acrobatic hang gliders that suffered structural failure.

                        Comment


                        • My girlfriend flew hang gliders, and they use a parachute in their harness cocoon - you have to pull it out and throw it, rather than it being ballistic.

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