"Modified Kombat Kopter"...    Lee Wayman finds a way to modify the metalic monster, The Airplane Factory`s unpredictable "kombat Kopter"..... into an excellent flying autogyro capable of slow as well as high speed maneuvering.....

Like many of us, Lee was not happy with his original Kopter.    Using his machining skills and ingenuity, he designed and built a 4 bladed metal hub, a direct servo controlled head, modified the downthrust from zero to twelve degrees of downthrust, made and installed new landing gear, and who knows how many other modifications, all combining to turn this metalic monster into a nice flying autogyro that can be probably flown by the average modeler... something the original was not.

Note: Lee has actually modified two KK`s, and the following photos are typical/peculiar to both models that lee has modified.  This will explain why you may note a particular mod not showing in some of the photos.  NOTE:  the most recent modification, as of mid-October, is shown at the bottom of this page....

Yes!  Believe it or not, here is a Kombat Kopter, highly modified , that Lee reports is very stable and fun to fly.....





This is another in-flight view, and you can see the lateral (direct control) servo attached to the mast post.




Note he has installed side plates to support the new 12 degrees of downthrust.   This adjustment tends to remove the tendency of the KK to ride nose high, thus greatly improving stability.



Lee has elected to cut new landing gear in two pieces, which he says is easier to bend in a vice.  Note that he covers his gear in a bright color for better orientation.... strictly a personal preference.
You can also see the additional plastic fuel cell installed on the bottom for housing the battery.





This is the lateral control mod accomplished on one model.




And... if you look close you can see that this is th lateral control arm mod for the other model.  In this situation you can see he has mounted the servo to the vertical mast support...an excellent idea!.




Here is a close up of the control arms of the model in the previous photo.



Lee has constructed all new blades with a much more efficient Clark Y airfoil.   This accomplishes two major goals..
(1) improves lift and eases the pre-rotation problem...
(2) Removes those dangerous knife-edge blades of the original factory model.  That strange "coil" around the blade is the heat shrink covering prior to being installed.




This a view of the root end of the blades showing the Leading edge wire bent around the end of the blade.
You can also see the mounting plates for these (probably) Balsa blades.




A close up of the new 4 bladed rotor flex hub.  The flange portion in the center houses the ball bearings.




The hinge material is grooved polyproplyene... look close and you can actually see the indented part used as the actual hinge area.



NOTE:  Here is Lee`s latest modification to the KK.... It is a "delta" hinged hub (mechanical) ... and angled at 20 degrees forward...

Lee`s comments:  "There are some good points that I really like about it.  The first one I noticed right away was how fast the rotors spun up. Really fast.  I would say it spun up and lifted off in about one half the distance than the flex head system.   It also seemed to climb out much faster.  I could fly around and gain altitude going into the very light breeze on one half throttle.   Also if I climbed a little to steep and it tended to stall, it recovered faster when I put the nose down. The main negative side of the system is I guess that it is much more difficult to build, beings that it is mechanical instead of made out of the flex material.  The other thing that I noticed is that it had a slight tendancy to roll off to one side or the other and not be "rock steady" in lateral stability like the flex hinge system is.   It's really not bad, but having the two to compare, one right after the other, I can spit hairs on the difference in performance between the two."

If you`d like to see the more detailed photos of this new hub design of Lee`s.... click here.

Note:  Jim Baxter followed Lee`s suggestions in regard to this model...
    for a complete rundown on his results,    click here...

Back to the homepage rev. 4-2-99..jb