Mini Bye Yak.

 

Last spring (2007) Paul and myself cut out a couple of sets of parts for a scaled down of E-flite Bye Yak (70%) for indoor flying but neither of us got around to finishing them at the time. I love the full size version and had flown the Bye Yak indoors but found it a little to big and heavy to fly in the size of halls we currently use.

My scaled down Ultimate 300 flies very well but lacks wing area which shows up as tendency to flick roll if the elevator is not used gentle. Scaling the Bye Yak to the same size (70%) and keeping below 6 ozs would give a 50 % lower wing loading than the Ultimate due itís much larger wing. The side area will help knife-edge flight and it was hopped it would fly as well as the bigger version.
Construction is my standard formulae as used on the little Ultimate

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. I had intended to use a small C22 out runner from Robotbirds but as the model took shape it became clear that it was comparable in size to the Extra 300 so a small Ikarus out runner  (same as the AXI 2204/54) but stayed with a 2 cell Flight power 300 mahr Lipo battery pack. All up weight 6.5 ozs. Control is by 4 Saturn 44 servos a Castle Creations Phoenix 10 ESC and a Hitec HFS 05MS Rx.

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The first flew flights of the Bye Yak were a little disappointing, lacking power and any duration. It wasnít until I was preparing the Extra 300 for flight that my mistake to came to light. The Ikarus is the same motor (different colour) as the AXI 2204/54  but on the Extra 300 I use 2 X 640 mahr Kokams.

With 640 Kokams fitted the Bye Yak proved to be all I had hoped for. It flies superbly so well that I didnít fly any other model on that night
. A latter check with a Watt meter proved what I should have known from the outset that the small 300 mahr Lipoís really are only suitable for very small motors.
 The slightly larger motors dragging the voltage quickly down.I
It is now flying superbly and is all I had hoped for, it flies quite slowly which makes conventional indoor aeros easier. On my recent visit to the Prague Model show I was very impressed with how slowly their indoor models were flying with out sitting very nose will be experimenting with a few aerodynamic additions to try to emulate their flying style.

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Mini Bye Yak with it's latest development.

Latest in the series.

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Gloucester Model Flying Club