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Dubai - WAG - Gyro down 9.12.15

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  • Originally posted by Sky Scooter View Post
    Easy Tiger this is a flight parameter that will kill you. If you unload your rotor you no longer have a rotor there just two metal flaps that will shake all way down. The altitude just gives you more time to think about your impact. This is what annoys me. The heroism and ignorance of flight parameters or theory. You have done an endorsement for Gyro copter, Think about it, Read your flight manual again...and again... got it now. what has been promoted in the previous post is the last flight you will ever experience, and to the euro hero your call but it's irresponsible to promote this as a suggested certified NEXT flight experience, For the sake of love of experience, violent stick shake or bruising legs , still cant fathom where your going wif this **** as it will kill you 10% of the 100% of chance.Guaranteed. actually i think your just taking the piss and looking for an informed response. actually just take it to another forum and you'll kill less. DIIIIICK. Let me guess GERMAN? Yers so full of S#!T
    Hey you go or i go happy either way cause you're irritating **** out of me rite now.

    I did not have the intent to promote anything dangerous in my post just pointing out the fact of negative G. Not every pilot has the same ability. So if some how you read into my post that I was ever promoting you should go out and try aerobatics in your gyro this absolutely was not what I meant.
    Last edited by Texasautogyro; 12-22-2015, 08:57 AM.
    ATP and commercial gyro CFI
    You tube channel "alaskanlimoguy"
    Gyro test pilot.

    Comment


    • Show It

      Originally posted by Aviomania View Post
      Abid.... read my early posts.... we did test negative G to the point the stick was shaking violently and bruising my legs.... so yes when i say it can be recoverable i have tested it. Unlike USA to get a certification in Europe requires tests. And just because i love to learn and experiment... i go a step further than the expected tests. i have demonstrated this in front of 14 people visiting from Greece. they actually have seen the rotor becoming flat instead of coned. I will not continue explaining my self or our models any more... it is not the right thread.

      we have given the information, me, chuck, David some others.... but is up to each one of you to think and decide. happy landings to every one.
      I know quite a lot about certification tests both in the US and in Europe.
      Number 1, the claim that somehow European tests and requirements are harder is absolute and complete BS. Doing more paperwork and having more red tape from NAA and EASA and getting even a DOA and POA does not amount to tests on the aircraft, its red tape at its zenith and Europe has more of it than even FAA. So lets not go into certification testing in Europe being required is superior to the US. In fact its the other way around. The problem is gyroplanes do not require certification because they are not factory built in the US. You would test to something close to BCAR Sec T. It is open and available to anyone to see.

      If you went to negative G than you don't need to explain. You simply need to list the test sequence and record max negative G on a G meter or an EFIS equipped with AHRS in its flight log and show the recovery in 150 to 200 feet of altitude loss.

      BTW, what you are describing sounds like lower than 1 G but not negative G in my educated guess but without proper data its hard to say either way.

      This would be equivalent of showing a spin resistant airplane design (like ICON) per some agreed upon standard (like Part 23 spin resistance) and would be great for you and your design but that type of thing is not required even in Part 23 certification because spin avoidance is taught to the pilots and if they do spin, many of them do die. FAA does not run around telling Cessna then to stop making 172 because only if they had spin resistance, the pilot who made the mistake had a chance.

      That is essentially what you and Chuck are saying. Instead of training pilots, we ought to poo poo any aircraft that does not have equivalent of spin resistant behavior because pilots die in spins. Exactly one airplane has shown spin resistance per Part 23 for the record and the compromise is they needed an extra 150 pounds of structure to do it and lost a lot of maneuverability and got a weight exemption. We all know (at least engineers and designers) that nothing in nature is for free. You make something work, you only do it by giving up something else and the pros and cons need to be weighed.

      Still that does not make it right to claim about this accident and about AutoGyro's design what you and Chuck are claiming in regards and relevance to this accident. It is not fair.

      Bottom line is the poor pilot was unfortunately not at the level where he should have participated in a pylon race for gyroplanes at World Air Games and did not even secure his helmet properly causing further contributing factor to his distraction when something went wrong and shoving stock forward is the wrong reaction (a la fixed wing) for a gyroplane pilot and leads to a negative G maneuver that is if not impossible, extremely improbable to retrieve from just like a flat spin in an airplane or tumble in a trike. Nothing in this is different in gyroplanes than in any other categories. Learn from this to honor his memory. Each category of aircraft has its gremlins. You want to do negative G stunts, fly an airplane. It is superior to gyroplane in this regard both is safety and controllability, no doubt about it.
      Last edited by fara; 12-22-2015, 09:04 AM.

      Comment


      • An online condolence book is now open for the pilot Arend van Randen - for those of you who my wish to comment the site can be found here. Google Translate can help.


        https://www.memori.nl/gedenkplaats/arend-van-randen/

        Comment


        • Originally posted by birdy View Post
          It costs no more to arrange the propeller thrust line to pass through the aircraft CG than it does to offset it.

          It costs no more to provide aerodynamic propeller torque compensation than it does to ignore it.

          It costs no more to eliminate slip-roll coupling than it does to ignore it.

          These coffin corners are so easily eliminated that their inclusion is indefensible.


          Rong, rong n rong CB.
          You know it too.
          There is a BIG cost.
          Asthetics, (apparently).
          In these modern times, if it looks the best, it is the best.
          And apparently , glorified bathtubs are the ducks nuts, no matter their configuration?
          .
          Really? What about putting the tub way close to the rotor blades, which would reduce very significantly what Chuck calls slip-roll coupling.
          The problem with that and so called CLT which also place occupants high up is that it increases the chances of flip overs or duck walking on the mains on the ground very significantly and those would be much more plentiful with new pilots than a PPO or slip roll accident because most of the pilots do not fly sideways at high speeds and new pilots tend not to slip much beyond coming in to land in crosswinds.

          Have you considered that in your calculus?

          Comment


          • A Cessna is CLT.

            A Dominator has its CG above the propeller thrust line.

            “Duck walk” is a function of suspension geometry, not CG height. Too much tire scrub Vs suspension travel.

            Obfuscation.

            Comment


            • Originally posted by fara View Post
              Really? What about putting the tub way close to the rotor blades, which would reduce very significantly what Chuck calls slip-roll coupling.
              The problem with that and so called CLT which also place occupants high up is that it increases the chances of flip overs or duck walking on the mains on the ground very significantly and those would be much more plentiful with new pilots than a PPO or slip roll accident because most of the pilots do not fly sideways at high speeds and new pilots tend not to slip much beyond coming in to land in crosswinds.

              Have you considered that in your calculus?
              I have flown several Dominators and not had them “duck walk” as I understand the term.

              I have watched several Dominators “duck walk” and it appears to me to be landing gear geometry and piloting technique causing it.

              All of the Dominators I have flown have been low thrust line gyroplanes rather than near centerline thrust.

              The Predator has a high body and even while training I have not had a student make it “duck walk” or even get one wheel very far off the ground while the other is on the ground.

              I hope I may get some training from Greg in your gyroplane so I can better understand how you have resolved the issues I have experienced in high thrust line gyroplanes that appear similar to me (MTO and Magni M16).

              I don’t think it would be a bad thing if the AR1 flew like either the MTO or the Magni M16 as they felt very safe to me.
              Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

              Comment


              • When I have seen duck walk it usually starts from side loading the mains or landing crabbed then gets aggravated by the pilot. This happens because they tend to move the stick forward or in an erratic manner. If this starts I try to teach keeping the stuck back because it holds the mains on the ground and prevents the nose wheel from contacting the runway. If the front contacts the pavement roll over can happen.
                ATP and commercial gyro CFI
                You tube channel "alaskanlimoguy"
                Gyro test pilot.

                Comment


                • Yes duck walking is a geometry force issue but obviously force vectors have magnitude and direction and if you mass distribution is higher up you produce more magnitude to the wheel due to moment arm.
                  Duck walking can start due to a bad landing technique (side load) or if the wheel toe-in (more than 2 degrees) is not correct or becomes incorrect over time. You point the fronts of your main wheels towards each other a bit much and land slightly wrong and you will have a duck walking incident. Flexure of the landing gear leaf backwards or forwards alternately can also create it in a bad landing.
                  Slop in frame (bolted frames) that develops over time, the wheels being close to the hang point instead of further behind them, they all create duck walking issues which almost always results in a flip over of a trike or a gyroplane.

                  The dominator develops a bit too much toe in after some time because the slop develops in the frame. It can be easily corrected with a bushing to size the holes right again (or in some cases make the hole square to the tube) and the toe in at rest should be checked each annual by owners to be less than 2 degrees, preferably 0. That's just how the design of Dominator is in placement of its mains to the hang point.

                  In airplanes you want slight toe in on tri-gear mains and slight toe out on mains on tail draggers We are talking about a degree.

                  But yes CG comes into play. Now lets move on. I am giving away too many tricks.
                  Last edited by fara; 12-22-2015, 10:30 AM.

                  Comment


                  • Steve thanks for the link.

                    Sincerely SWilliams

                    Comment


                    • Cierva’s last FW design, a trimotor bomber designed for the Spanish Air Force, crashed during its first flight when the pilot made a low, slow turn and stalled.

                      His search for a safe, stall proof and spin proof aircraft led him to the invention of the Autogiro.

                      He didn’t stop with spin proof and stall proof. He eliminated all of the coffin corners one by one.

                      According to Peter W. Brooks in “Cierva Autogiros,” 30,000 hours were flown in Autogiros before the first fatality occurred. The fatality rate for general aviation in the US in 1939 was one per 5,000 hours.

                      Now some are saying, “leave in the coffin corners and blame the pilot for splattering.” Or; “propeller torque can be solved by trim springs, offset of rotorhead and harmony.”

                      Comment


                      • Mr. BeatyI don't mean this question in a derogatory way,but what designs do you have

                        that will help eliminate the coffin corners you keep refering to ? If you have designs, what

                        gyros have been using them ?




                        Best regards,
                        Best Regards,
                        Eddie Sigman,Polvadera,nm
                        (575) 835-4921

                        Comment


                        • Ron Heron’s LW designs of some 20 years ago eliminated torque roll, PPO and slip roll coupling.

                          The Aviomania gyros are the most recent designs to eliminate those flaws.

                          Here’s a perfect example of a torqueover fatality:

                          http://www.ntsb.gov/_layouts/ntsb.av...no=3&pgsize=50

                          This accident has many similarities to the one in Dubai: zoom climb, pushover and reduction of rotor thrust to a level that could no longer resist propeller torque. Zero “G” is not required for torqueover.
                          Last edited by C. Beaty; 12-22-2015, 12:09 PM.

                          Comment


                          • Duck walk results from the use of a simple swing-arm landing gear axle (a la the early VW Beetle, Corvair, etc.). It has zero to do with CG height. To eliminate duckwalk, a designer can copy the wide outrigger oleo gears common on 1930's aircraft, including the Cierva gyros and countless others. Their wheels move straight up under load, instead of up-and-out. There are penalties to doing so, in cost, weight and drag. (At least for training gyros, I think the more complex, forgiving gear would be a worthwhile tradeoff; one of my students just about lost my Dominator trainer in a duckwalked landing.)

                            Moving the body pod up to align CG and prop thrustline pays at least triple dividends: It reduces frontal area by placing engine and cabin in line with each other; it eliminates pitching reactions in a destabilizing direction with throttle changes, and it makes it easier to eliminate proverse slip-roll coupling. Properly done, it looks just as sexy as a lowrider config, in my opinion.

                            Raising the body does not help with torque roll; that is most easily done with fins deployed symmetrically in the propwash. You need fins back there anyway, so there need be no weight or cost penalty. Displacing the rotor thrustline off to one side of the CG is not a safe substitute for the anti-torque fins, as rotor thrust comes and goes, whether you toss the stick around or not.

                            Gyro rollovers on the ground are almost never simple static tip-over events caused by high CG; how many times have you had a gyro fall over with its blades stopped or turning at 50 RPM? Rather, most of these events are "lift-overs," powered by a rotor that's nearly at flight RPM. I've been the crash dummy in a couple of these expensive events.

                            As discussed here many times, you can see a torque roll component in the Pee We Judge crash film and the couple of PPO films from Japan that have been posted/linked on this Forum over the years. We are properly upset that this problem MAY have contributed to the loss of another brother, even if there were other factors. IMHO, we should fix what we can fix.

                            Comment


                            • Thanks for the Info about designs.






                              Best regards,
                              Best Regards,
                              Eddie Sigman,Polvadera,nm
                              (575) 835-4921

                              Comment


                              • Originally posted by Doug Riley View Post
                                We are properly upset that this problem MAY have contributed to the loss of another brother, even if there were other factors. IMHO, we should fix what we can fix.
                                How can you be properly upset that this problem MAY have contributed to the loss? Particularly when it MAY have contributed in any gyro. There simply is no data that anyone can produce that their gyro MIGHT be more or less likely to do what this gyro MAY have done. It all just gets more and more absurd. Everyone is an expert on how bad the Eurotubs are despite the fact that many have not even flown one. Yet who else besides Autogyro, Magni, ELA, Titanium,, Apollo etc are mass producing a gyro that any aspiring gyro pilot can buy, fly comfortably cross country for 250 plus miles with a passenger etc, etc. Yes even circumnavigate the globe or cross the US. Not a single one of the so called experts is actually doing this on any type of scale that makes these gyros available to us. Furthermore none have truly demonstrated that they can build such a gyro, and take it to Dubai and knock the crap out of the competition without a single 'coffin-corner'. If you guys can build such a gyro you clearly will build a gyro that will beat the hell out of any MTO in Dubai, as your gyros clearly do not have any limitations. So do it, show us.
                                I would be happy to pay the $80,000 going rate for such a perfect gyro if someone would produce one.

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