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photo comparative crash damage to various gyro rotor systems

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  • #16
    Originally posted by Kolibri View Post
    WaspAir, I can recall at least one: the N69EP Ortmayer trainer. And that wasn't even from any impact.
    Its overly long used RAF hub bar failed at a tensile bolthead, and that rotor fatally struck the cabin-seated student in the head.

    Seems prudent not to chance it.

    I'll still stick with my premise, that rotors should not be routinely flung off from impact, much less from mere tipovers.

    It doesn't sound to me like that Ortmayer incident fits the pattern from the posted photos. You've been showing post-impact rotor blade damage / blade separation, and I asked about the risk to bystanders of such things, not about pre-ground-impact or in-flight failures leading to crew injuries.

    If you look at certified standard airworthiness and military helicopters, all with rotor systems built to standards well beyond anything from anybody in the sport gyro industry, they throw all sorts of bits around in dynamic rollovers and ground resonance incidents, the events I would consider most analogous to gyro tip-overs with respect to the risk to ground personnel. For example,
    Boeing Vertol https://www.youtube.com/watch?v=XWpeFY53qWM
    Sikorsky/Schweizer/Hughes https://www.youtube.com/watch?v=IN2Bw79KK80
    Eurocopter/Aerospatiale/Airbus https://www.youtube.com/watch?v=z_kuB0SCCe4
    Bell https://www.youtube.com/watch?v=TEBckxf8RI0


    Apparently, the federal airworthiness authorities do not consider failure to retain rotor blades (or parts thereof) post ground contact to be of sufficient public risk to warrant regulation, because all these designs are approved.
    Last edited by WaspAir; 08-09-2018, 11:35 PM.

    Comment


    • #17
      Kolibri, since you seem to want everyone to switch to SC, can you show us the sale of your RAF ? Show us your " put your money where your mouth is " by the purchase and registration of your own SC. Please show us an inflight photo of your side by side SC that you seem to keep bringing up as the standard for two seaters. Until then I feel you are less qualified to pontificate on these matters than those that own and chose to fly these other brands you seem to disapprove of.
      ​​​

      Comment


      • #18
        Kolibri

        I notice all of the examples you cite are of aluminum rotor blades, such as used on the Sportcopter, and rotor hubs at least similar to the Averso Stella. What did you discover regarding composite blades and other hubs, such as on the Titanium and Magni?

        /Ed

        Comment


        • #19
          Originally posted by fara View Post

          That is not correct at all about Zenith.
          It was found that the wing load testing was done incorrectly and when the load testing was done correctly, the wings failed at high but potentially attainable G load. Thus FAA on NTSB's recommendation grounded the whole fleet in the US. UK CAA and Dutch CAA had also grounded the whole fleet. They forced the company to release a mandatory safety directive which added a lot more metal to the spars inside the wing to pass the load test (18.5 pounds worth to be exact) and since then there have been no failures. I personally know at least one FAA examiner who died in a 601 due to a wing coming off. I do not think he needed any further training to be safe. I know a second FAA examiner and friend who came back down from a check-ride to find that one wing was about to go and its leading edge was out partially at the root from the carry through structure.
          It was also found in flight testing that the stick force versus G load was not positive and in fact went opposite at speeds close to VNe and that is not good at all and that caused many pilots t go past VNe because of reversed feedback feel.
          https://www.aopa.org/news-and-media/...control-forces
          I think I said the same thing without all the facts you added:

          I said "Back when five Zenith 601 FW crashed worldwide in the span of a year, a lot of testing and time was wasted looking into flutter, weak spar, and touchy controls. Since then, I don't think one has crashed in the same way but it was more about training than anything else."

          My point that seems to be missed is that training prevented any further incidents. It is my opinion as a 601 builder that the "magic" fix was the education of all owners through a widely publicized defect. Yes, it was a defect. And, no, not all owners opened their wings to install the spar brace. And yet, the failures stopped immediately. I don't want to take away from Kolibri's thread so lets leave it at that - we agree on the three causes.

          When I see posts on this forum recommending that a new gyro owner fly 100 hours before taking up a passenger, I see some very smart advice. My CFI shook my hand when I got my ticket and the told that I have a license to practice. I took that to heart. My personal opinion, right or wrong, is 99 out of 100 crashes are pilot error. I say that even if it's an engine out situation. We are TRAINED to handle engine outs so shouldn't we survive that situation most of the time?
          Last edited by HighAltitude; 08-10-2018, 06:22 AM.

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          • #20
            Tim I think anyone with just a little common sense won't take passengers until they feel confident about there

            ability to fly a Gyro,there was a time period that I didn't want to even take myself up,my problem was with the takeoffs/landings

            the flying in between was easy and enjoyable the TO's and landings were shear terror for a while.
            Best Regards,
            Eddie Sigman,Polvadera,nm
            (575) 835-4921

            Comment


            • #21
              Originally posted by Kolibri View Post
              Folks, I've not accused any gyro mfg. of anything. Haven't "bashed" anyone. Just showing post-crash photos.
              What they may or may not mean is for another discussion, after lots of photographic data.

              loftus just posted more of an "infomercial" for AG than I did for SC.
              I'm really not trying to promote AG at all; just trying to establish whether there is any cause for concern amongst current AG owners - and there are many as I noted above - that their aircraft are structurally unsound and hence inherently unsafe to fly. I am just not aware that there are ongoing problems with AG aircraft and rotors from a structural standpoint. I am aware that there were some problems in the past.
              With regard to accident scenarios, I don't get much information from post accident photos showing bent or broken rotor blades with regard to how this effects in flight integrity or pilot safety during an accident event. I would be most interested in all manufacturers taking steps to increase pilot protection. Probably a roll cage / air bags etc would be the most valuable development.

              Comment


              • #22
                Of all the rotor-related ugliness I read about on the forum (the infamous "flap", poor rotor management, zoom climb/pushover disasters, etc.) nearly all of it seems a product of the general configuration (teetering two-blade fixed collective) rather than any weakness in particular masts, rotorheads, or blades used to implement that design choice by various competitors. I will quite candidly admit that I really don't like the design that has been legislated into permanence by the light sport/sport pilot rules, and much prefer a proper articulated rotor system to the limitations of the current cheap/simple design path. However, given that most gyro folks are stuck with that choice, I don't see a meaningful safety issue or urgent need for corrective action arising from failure to retain blade bits post-crash. I certainly don't see a basis to choose one manufacturer over another based upon the way ruined blades look after they are ruined; bent, twisted, thrown, or broken, they're all just trash now.

                Comment


                • #23
                  It doesn't sound to me like that Ortmayer incident fits the pattern from the posted photos. You've been showing post-impact rotor blade damage / blade separation, and I asked about the risk to bystanders of such things, not about pre-ground-impact or in-flight failures leading to crew injuries.
                  WaspAir, the Ortmayer/RAF hub bar bolt failure is related, because it evidenced a weakness of that system.
                  System weaknesses are what I'm attempting to discern through this thread, as my first post stated:


                  I'm currently looking into comparative mast/rotor system strengths of various gyros, as evinced by their post-crash condition.
                  Consistent points of breakage from impact illustrates a system's weakest areas.
                  If you look at certified standard airworthiness and military helicopters, all with rotor systems built to standards well beyond anything from anybody in the sport gyro industry, they throw all sorts of bits around in dynamic rollovers and ground resonance incidents, the events I would consider most analogous to gyro tip-overs with respect to the risk to ground personnel.
                  That's not surprising to me, since helicopters have powered rotors. I would expect the additional energy to cause dramatic rotor breakages.

                  I certainly don't see a basis to choose one manufacturer over another based upon the way ruined blades look after they are ruined; bent, twisted, thrown, or broken,
                  What you're still missing is the disparity of crash damage between mfg.
                  How/why do some consistently break (and at the same place), while another doesn't break at all?
                  I'm surprised you're not curious about this.

                  Also, a rotor system that doesn't break from impact seems nearly impervious to failure during mere flight, due to massive reserves of strength.
                  I like that. YMMV.



                  _____________
                  Kolibri, since you seem to want everyone to switch to SC, can you show us the sale of your RAF ? Show us your " put your money where your mouth is " by the purchase and registration of your own SC. Please show us an inflight photo of your side by side SC that you seem to keep bringing up as the standard for two seaters. Until then I feel you are less qualified to pontificate on these matters than those that own and chose to fly these other brands you seem to disapprove of.
                  Tomgyro, what an odd notion considering that I've already been flying Sport Copter rotors for nearly three years.
                  The Vortex M2 prototype will first fly this month, so nobody yet has a production model, not even Jim Vanek.
                  I'll have one of the first M2s in the USA, and my RAF is soon for sale.

                  Also, I've not been hawking SC or the M2 here. I answered loftus's question. I posted crash damage of Sport Copters. That's it.



                  _____________
                  What did you discover regarding composite blades and other hubs, such as on the Titanium and Magni?
                  EdL, I'm working on that. Fewer examples on record, though.



                  _____________
                  I'm really not trying to promote AG at all; just trying to establish whether there is any cause for concern amongst current AG owners - and there are many as I noted above - that their aircraft are structurally unsound and hence inherently unsafe to fly. I am just not aware that there are ongoing problems with AG aircraft and rotors from a structural standpoint. I am aware that there were some problems in the past.
                  loftus, "some problems in the past" rather understates things, doesn't it?
                  AutoGyro's Rotor System 1 was considered timed-out by 700 hours due to consistent bolt hole cracking. That was not even a decade ago.
                  Rotor System 2, as far as I know, has merely revised tension straps, yet upon impact the rotors shear off from the same area as were cracking in Rotor System 1.
                  Does this connote a problem? Let's find out beforehand, not afterward.
                  Are AutoGyro owners curious enough to learn for themselves, or will they simply believe the university study that AG commissioned which claimed a curiously round figure of 2500 hour life of RS2?
                  Are there any RS2 systems with anywhere close to 2500 hours, and which have been inspected?

                  If a small company like Sport Copter can consistently build a rotor system strong enough to withstand impact without breaking,
                  then why hasn't the
                  "market leader" AutoGyro done so with all their European engineers? Where is the legendary robust German strength of their product?

                  That said, I'm continuing to search for any photo of a broken-off SC rotor. Contributions there are welcome.
                  Also, without much success, I'm searching for photos of AG rotors that have remained intact with their hub bar after hard impact.


                  Regards,
                  Kolibri
                  Last edited by Kolibri; 08-11-2018, 03:04 PM.
                  PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders; checkride soon

                  Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

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

                  Comment


                  • #24
                    What you're still missing is the disparity of crash damage between mfg.
                    How/why do some consistently break (and at the same place), while another doesn't break at all?
                    I'm surprised you're not curious about this.

                    Also, a rotor system that doesn't break from impact seems nearly impervious to failure during mere flight, due to massive reserves of strength.
                    I like that. YMMV.

                    Kolibri

                    massive reserves of strength is what breaks blades on impact.
                    The extruded blades and composite seem to snap more readily is because they have no radial give.
                    The bonded blades use .024 skins with no foam or internal structural support.
                    Most composites have internal foam and a full wrap around skin that can be up to .062 to .090 thick..
                    The sky wheels are hollow and have two bonded skins that are .030 which will separate on impact and 99% will stay in one piece.
                    Mini 500 blades and most composites will snap at the root on impact.
                    Most extruded blades have thicker skins and internal webs, depending on alloy will also snap at the root.
                    The 6063 extrusions always impressed me because they are so soft, but yet very durable.
                    I've always expected them to bend in fight.!! but after 20 some years of watching them fly, I'm still amazed and most stay together on impact.


                    .
                    Life,The leading cause of Death

                    Live and Learn--OR--Die and be an example

                    321.252.7705

                    Comment


                    • #25
                      Jake has the answer,Sportcoptor blades are very soft they don't break they just bend like

                      a piece of rope would.I will just stick with the helio industry standard, solid carbon fiber blades.

                      I suppose if all of the accidents were exactly the same then there could be a comparison of some kind I

                      don't know what good it would be.All of the current blades seem to be working just fine,all aviation

                      manufactures have all sort of problems when introducing a new product,boeing,airbus,cessna,etc,and

                      I suppose gyro's are not immune from problems either.

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

                      Comment


                      • #26
                        massive reserves of strength is what breaks blades on impact.
                        gyrojake, I don't at all follow this statement. If that's true, then all the broken rotors must have been the strongest ones???

                        Also, Sport Copter rotor skins are not 6063, but 6061-T6 (aircraft grade, not T6 wannabe, or T4 hardened after extrusion).
                        The skins are bonded using Boeing's epoxy method, which is expensive and time-consuming. The skins don't peel off from impact.



                        ______________
                        Jake has the answer,Sportcoptor blades are very soft they don't break they just bend like a piece of rope would
                        Uh, sorry, eddie, you've got that backwards.
                        Magni blades are very soft. Sport Copter blades are quite rigid, and do not bend (much less like a piece of rope).
                        This is how they tolerate a moderately negative pitching moment (without tucking) which helps to provide higher cruise speed.

                        For example, this SC rotor was flapped into the prop, and the newbie soloist didn't realize it and took off anyway.
                        Did a pattern, landed, and then saw the damage. Rigid, not soft.

                        Regards,
                        Kolibri


                        Click image for larger version  Name:	Sport Rotor surviving prop strike.png Views:	2 Size:	259.7 KB ID:	1136546

                        Last edited by Kolibri; 08-11-2018, 03:22 PM.
                        PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders; checkride soon

                        Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

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

                        Comment


                        • #27

                          gyrojake, I don't at all follow this statement. If that's true, then all the broken rotors must have been the strongest ones???

                          Also, Sport Copter rotor skins are not 6063, but 6061-T6 (aircraft grade, not T6 wannabe, or T4 hardened after extrusion).
                          The skins are bonded using Boeing's epoxy method, which is expensive and time-consuming. The skins don't peel off from impact.
                          Kolibri

                          I never said that S/C blades were 6063 I said the Extruded blades. I never specified their alloy.
                          A blade that will fold and collapse will stay together better than a blade that is solid and rigid
                          I have damaged examples in my shop.
                          Most blades that break at the root do not bend as much to absorb energy axial rigidity adds lever to the force and breaks at the hub.
                          Simple mechanics Dude.
                          I use the same stuff to build my helicopter blades, not that expensive or time consuming. So simple even you can do it, as long as you can set the temp on the oven and close a few clamps.
                          You need to read and understand, not read and speculate meanings.
                          I guess you just like to argue
                          Life,The leading cause of Death

                          Live and Learn--OR--Die and be an example

                          321.252.7705

                          Comment


                          • #28
                            Due to diverse opinions in this thread, I've started a new poll on the subject.

                            During tipovers and crashes, rotors which often break off from the hub bar are . . .
                            https://www.rotaryforum.com/forum/eq...he-hub-bar-are

                            PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders; checkride soon

                            Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

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

                            Comment


                            • #29
                              A blade that will fold and collapse will stay together better than a blade that is solid and rigid
                              But the Sport Copter blades are more solid and rigid than others, yet they do not seem to break.
                              But they should break, according to your argument.


                              axial rigidity adds lever to the force and breaks at the hub
                              Again, then SC rotors should be breaking at the hub, but they're not.

                              You need to read and understand, not read and speculate meanings.
                              My goal is to read and understand. Perhaps you could write with more clarity? Thanks.
                              PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders; checkride soon

                              Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

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

                              Comment


                              • #30
                                Originally posted by Kolibri View Post
                                But the Sport Copter blades are more solid and rigid than others, yet they do not seem to break.
                                But they should break, according to your argument.



                                Again, then SC rotors should be breaking at the hub, but they're not.


                                My goal is to read and understand. Perhaps you could write with more clarity? Thanks.
                                Sport Copter blades are HOLLOW with a solid leading edge which allows the blade to deform and absorb impact better than a solid or extruded blade.
                                What do you mean S/C blades are more solid? Again, they are HOLLOW .
                                My correspondences are very clear, you're just arguing a point you are ignorant of.
                                I'm beginning to like you, you are a challenging individual with no real experience in mechanics and are trying to be the master.
                                It's guys like you that make my Dumb Ass look good.
                                Keep up the good work.
                                Life,The leading cause of Death

                                Live and Learn--OR--Die and be an example

                                321.252.7705

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