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Taildragger vs. trike in tractors

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  • Taildragger vs. trike in tractors

    Hi all,Can anyone explain to me why the greater proportion of tractor gyroplanes are taildraggers?I know that Juan de la Cierva made his tractor designs from fuselages of old aircraft and nearly all aircraft in those days were taildraggers.I also know that many gyro pilots favour trike/conventional gear arrangement due to ease of use and other features like being about to pivot/rotate around the CoG etc which, I understand, has its advantages.I know that flying a taildragger is more difficult, especially in gyros, as you don"t roll, rotate and leave the ground in the same way you do with a fixed wing taildragger.I also understand that tractors often require a longer tailboom to make use of greater turning moments due to issues with thrust coming from all the way up the front of the aircraft, instead of smack-bang in front of the rudder, and so a taildragger arrangement can have its advantages in this configuration.I noted that when Murray designed "Tugger", he orginally intended for it to be a taildragger but due to unspecified reasons, changed it to a conventional design. However, when building his Little Wing, he was happy to leave it as a taildragger (as the receipe calls for!)Is there, then, a functional reason for tractors more often that not having a taildragger arrangement or is this simply an homage to Cierva/simplicity of design?Thanks.

  • #2
    In My experience I see no logical/practical reason for a gyro to be a taildragger,maybe a bit of nostalgia but thats all.A CLT tractor is no more stable than a CLT pusher.The thrust is going through the COG,doesn"t matter from which direction.You can have the horizontal stabiliser just as far back in either design as well.I have about 7 hours in the littleWing now and had to learn to fly all over again.Although no real difference in the straight and level stuff but takeoffs and landings need to be precise.Building is no different apart from needing more forward stick travel to get the torque tube level to help wind down the blades.Have attached drawing of what I would build one day,somewhere between project 4 and divorce.

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    • #3
      Thanks, Murray. I figured as much, but wanted to be sure.I"ll still stick with a Rod Torr Drop-keel design at this time but still have the odd fascination with tractors.I just like the elegance and simplicity of taildraggers, but also having taxied too many conventional undercarriage fixed-wings across bouncy, uneven grass strips with a panicky instructor giving me grief and constantly reminding me how nosewheel struts are often very weak, and can give way, thus ruining a prop and having an expensive knock-on effect to the engine and crankshaft!...somewhere between project 4 and divorce.Hah! That reminds me of a little anecdote.You see, I was at one of the many gliding clubs that I"ve frequented over the years, and a couple rolled up for a TIF.The president was there and was being all charming and chatty, to make them feel welcome.He then pointed to a seasoned member who has been in gliding for countless years, and said, "Now this is Bill. He suffers from AIDS!"The visiting lady flushed red, and responded with a serious and concerned, "Oh, that"s not good!"The president then continued, "Yes, that"s Aviation Induced Divorce Syndrome!"

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      • #4
        On one of my rare visits to the forum I"ll jump in on this one.Quite a few will know that for far too long I"ve been working on a 2 seat side by side tractor with chrome moly truss airframe, originally set up for a Mazda renesis (160hp), but replaced 2 1/2 years ago with a 9 cylinder Rotec radial (150 hp). Progress is painfully slow because I have a demanding worklife and am also usually buried under a pile of ASRA work at any given time.The original setup for the Renesis was nosewheel, but with the radial setup weighing about 45 lb more than the Renesis setup, during the initial frame hang testing with the Rotec installed it hung about 22 degrees nose down. Gross weight also became an issue, so in recent times I have been gravitating toward a tailwheel arrangement. I have also figured out a way to bring the engine rearward by 3 inches (by recessing or "dishing" a part of the firewall into the cabin to give clearance for the Rotec radial engine air cleaner) and will finish the revised shorter engine mount sometime in December. Moving the engine back 3 inches might noticeably reduce the excessive nose down hanging - we"ll just have to wait and see.My experiments to date clearly show that tailwheel configuration will definitely be the lightest, but requires the mast to be fitted with less rearward tiltback because instead of having a nosewheel ahead of the C of G you now have the weight of both mainwheels. Of course, the final mainwheels could well turn out to be spoked motor cycle wheels, enhancing a 1920"s-1930"s retro look. More experimentation needed.On the other hand, I"ve experimented by temporarily rigging up the original tricycle undercart with the radial and have discovered that you end up having a short wheelbase between nose and mainwheels, (shorter than a Cessna 150), which will undoubtedly lead to uncomfortable bobbing up-and-down taxying. Shorter even than on the oddball Russian Adelle AG tricycle machines (look on google images) and you"ll see what I mean - short wheelbase.So, being poised at the moment to either fit the original tricycle undercart, or go full tailwheel, I need to make the vary hard decisions one way or the other this summer. Thankfully having a frame and engine already available means I can endlessly experiment and hang test with all the various wheels and collection of undercart bits I have in my collection (now almost a museum!).I flew winjeels, tiger moths, cubs and citabrias (all taildraggers) a very long time ago, and still remember keenly how you have to always be on your guard to avoid a tail swing while rolling on the ground after landing with power off and with a sidewind component (this swing is called a "ground loop") because once it starts it can get very bad real quick. Recent discussions with Murray have reinforced those ancient memories. From a safety perspective a tricycle arrangement is far safer because it has an inherent tendency to self-correct (at anything up to about 15 degrees off centreline) whereas a tailwheel arrangement can "ground loop" you if you are drop your guard or are a bit complacent in the power off sidewind situation described above. Taxying tail draggers around before and after flying can also be an awkward pain, because when you turn fully crosswind from the into-wind position the now-sidewind component might not easily let you continue to turn your nose to downwind, and in those circumstances you often need a bit of rolling speed and a burst of power and out-of-wind rudder to complete the turn just at a time when you don"t actually want much speed or power. Sometimes tricky, is what I"d call it. So - dilemmas, choices, dilemmas, choices etc etc etcMark ReganVery occasional forum vistorBoard member & current Tech Manager

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        • #5
          Dear Mark,Just wondering, would toe brakes remedy the problem of turning when taxiing?Mark H

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          • #6
            Hi Mark,independent toe brakes are practically indispensible in a tail dragger, although Tiger Moths for instance don"t often have wheel brakes fitted and usually rely on the tail skid for friction. The crosswind taxying issues I wrote about were mostly experienced in planes fitted with independent mainwheel brake circuits while standing firmly on the downwind toe brake!As best I can figure, the tri-gear total setup is about 38 pounds heavier than a tailwheel setup, and that"s significant. Also, the short wheelbase issue with the tri-gear I wrote about in my earlier post is a real problem - taxying with a short wheelbase can be really dinky and unpleasant and dropping into potholes accentuates the tendency of bobbing up and down like in a rocking chair. You also have the prospect of a nosegear collapse badly damaging a $25,000 engine.Posting these comments has actually assisted me to clarify my thinking and as I write this I"m swinging toward tailwheel. Also, I guess that in low-wind or nil-wind conditions a tail dragger would provide the best taxying with absolutely no "rocking chair" bobbing, and I"m hoping that those ancient taildragger "frights" I gave myself and the ground handling lessons I learned the hard way might still safeguard me right through to the present day!Cheers,Mark Regan

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            • #7
              Hey Mark R, now that I am possibly the most experienced taildragger gyro pilot in the country(7 hours) I can use my vast experience to help you get airborne safely!The good thing about gyro"s over fix wing taildraggers is you tend to have a lot of power on when at relatively low takeoff speed,giving a lot of rudder authority.Mark H, my gyro has independent hydraulic disc brakes, you couldn"t safely taxi without them.

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              • #8
                I know this is an old thread, but still really interesting I reckon.Most gyros are probably

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