ISON Tandem AirBike Builder's Log

April, 2001
Sun 'n Fun fluff, and some building progress. Really.


One of the first things I saw at Sun 'n Fun this year was this Avid "Champion Ultralite" with Junkers-style ailerons. I didn't notice if they could be deployed as flaps, but I did notice a quite convoluted pushrod system between the stick and the aileron torque tubes. Very bizarre. An old-fashioned wire rope trailing edge causes the scalloped look and adds a nice touch.


I was fortunate to get 3 rides around the Sun 'n Fun pattern with my friend Les in her Flightstar II, newly modified to be an ultralight tug. She was giving demo rides for Flightstar, and I happened to be there when no one else was in line.

This view shows her emergency towline release hook, using a sailboat spinnaker release made by Wichard in France. This precision-forged release is a little expensive, but probably a good alternative to investing the time and labor required to make one like this...

This is the towline release used on the Bailey-Moyes Dragon Fly tug, and I assume they make it themselves. I believe it is styled after traditional sailplane-tug releases, and it appears to be very simple and reliable. It is important to a tug pilot's self-preservation (and to the safety of the soul being towed) to be able to reliably release a glider RIGHT NOW in case a problem develops during a tow (such as a mechanical problem or a glider approaching an unrecoverable lock-out situation).


This Dragon Fly is equipped with a 582 and the six-blade Ivoprop setup (see April 2000 for more on this rig).


Same plane, showing the Dragon Fly's version of Junkers flaperons. These surfaces are permanently angled downward to act as flaps, and are only adjustable in-flight as ailerons.


Here's the Bailey-Moyes Tempest ultralight sailplane, something I lust after very much as a companion to my AirBike tug. An unpowered glider weighing less than 155 lbs, such as this one, qualifies as an ultralight (assuming the other Part 103 rules are met).

Also notice in the background the "floatplane" made by Bob Bailey. It is a very clever pusher amphibian using one full-size airplane float for its fuselage.


This year I spent several days at the Quest Air Soaring Center W-NW of Orlando. This is a wonderful hang gliding center, and also happens to be the home of the Dragon Fly tug (shown here towing a hang glider aloft). Bob Bailey has his workshop here where he assembles RTF Dragon Flys (Flies?) for those who don't want to build the kit. In the right foreground, a pilot places his glider on the launch cart which will remain on the runway after he lifts off.


As I left Quest Air, they were hosting a major hang gliding championship. Pilots from all over the world were there, as well as high-performance gliders of all kinds.


I did have some progress on my Tandem this month, although it won't look like much here. A lot of time was spent laying out the rivet-hole modifications to the Zenith flaperon skins and drilling the new holes. I had to be very careful and methodical about this to prevent mistakes.

The ribs were laid out to match the hole spacing in the skins as well as the hinge bracket locations on the modified Tandem wings. The ribs and spars are all drilled and held together with temporary Cleco fasteners. Now I'm trying to arrange a work session with a couple of assistants to help me fold the skins over, locate the rib/spar skeletons in the proper place and drill the holes which will be used to rivet the skeletons to the bottom of the skins. After all parts are aligned and drilled, everything will be taken apart and primed before final assembly.


Good judgment comes from experience.
Unfortunately, experience usually come from bad judgment.