*****Skyote #88 gets Bronze Lindy for "Airventure-Oshkosh 2016 Plans Built Champion"******

October, 2007

Welcome to "Skyotelog", the build record of Skyote #88. I assume that you are familar with the Skyote biplane. If not, you should visit http://www.skyote.org/ for a complete introduction to this unique but elusive biplane.

The posts are presented in reverse chronological order (newest first). Or you can click on one of the "Labels" to see all of the posts concerning a specific topic. Click on any photo for a larger image.

All my building experience is limited to Van's RV's so I have no experience with building tube and fabric or "plans building". I have much to learn so take everything I write with a grain of salt and reasonable skepticisim.

I do not intend to follow a "traditional" path for the construction of #88. I intend to employ low level technology and $ to reduce the construction time and difficulty where possible and practical. By low level technology I am referring to CAD, laser, waterjet, CNC. For example:

  • I have purchased a complete wing spar kit from Jerry Kerr.
  • A rib kit from Mr. Bartoe.
  • Brunton Flying Wires and Drag wires from Harvey Swack.
  • CNC profiled tube kits for the fuselage, tail feathers and landing gear from VR3.

In addition I have converted all of the wing fittings, brackets, links, lugs etc. to CAD and had them cut by water jet. I have designed a laser cut wing spar drill template/jig which positions the five spar components so that all of the holes can be drilled in a complete spar as an assembly. I plan to continue converting as many parts as I can to CAD so that I can reduce the "hand-made" components to a minimum.

Note: As of June 2015 I have over 100 CAD files which provide 600+ water jet cut parts for the Skyote.

While it takes a little time, converting the design to CAD is a great way to truly understand the drawings. plus a huge amount of information has been extracted from the rather complex drawings. This can be a great help to others in understanding and interpreting the design.

The Skyote is uniquely suited for conversion to CAD in that a "computer" was used in it's original design. I have read that Mr. Bartoe used a HP calculator to "compute" the design and dimensions of the Skyote. The plans show all of the critical dimensions to three decimal places for X,Y and Z axes.

Amazingly, when I put the design into CAD the resulting 3D models agree with Mr. Bartoe's thee decimal place dimensions about 99.9% of the time. I have found one discrepancy but less than 0.030"!

If you want to build your Skyote as cheaply as possible, or if you enjoy handcrafting the same parts over and over again then my approach to building is not for you!

If you want to build your Skyote in the minimum possible time with highly accurate parts then this approach may be the answer. I personally get a lot of satisfaction out of organizing the project so that it can be produced accurately. Hopefully some of this work will prove useful to others in the future.

Comments are welcome. I will respond as time permits

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Sunday, August 30, 2009

Throttle/Mixture Quadrant Completed

Eventually you have to quit designing and cut some metal! I decided I had reached that point with the throttle/mixture quadrant so I machined up the latest version this weekend. I haven't drilled the attach holes for the throttle and mixture cables yet as I want to confirm the correct position with everything in the airplane. The paper pattern is still on the back side of the levers and shows the likely position of the attachment holes for the control cable ball ends. Also, black and red spherical knobs will be pressed into the ends of the handles when they arrive.

This design works on the same principle as Pete's design using bellville washers but has been modified to include the mixture control as well as forward stops for both throttle and mixture. I will likely add a small lever to the friction adjust knob when I can determine the correct location so that the lever will wind up in the correct position for easy adjustment.

The action is good and smooth with the friction adjustment being fairly linear through about 1/4 turn of the friction adjust knob. Each of the controls is isolated so that movement of one control does not affect the other control or the friction setting.

Saturday, August 22, 2009

Cowling Progress

Dale has continued to pound metal and as a result the cowling is really taking shape. Forming the "eyebrow" cooling ducts has been quite a challenge but they are almost finished. We used a fiberglass cooling duct supplied by Jabiru as a model but the duct we used has been replaced by a later model which gives "better cooling". Hopefully this design will work okay for the Skyote.

Throttle Quadrant Re-Do

I built a model of the previously proposed "pony brake" style throttle quadrant which was less than satisfying in relation to the smoothness of the action. As a result I have gone back to a design much closer to Pete's original design. It uses a stack of Bellville washers to develop the friction when compressed by the knurled knob. A mock-up of this arrangement gave very smooth action so this will likely be the final design.

This part is made from 1/4" 4130 and welds to to the diagonal fuselage tube in the appropriate position. It provides the basic mount for the quadrant and provides the anti-rotational anchor for the shoulder bolt which serves as the pivot for the throttle and mixture levers. The shoulder bolt and the bellville washers came from www.mscdirect.com and the 1/8" phenolic for the friction washers came from Aircraft Spruce. The levers are fabricated from 0.070" titanium and the knobs from 6061-T6.