Ding’s Denny Dart Mk II With Wing and Tailplane Shims

 
I built a wing with a 5.7 degree shim at the leading edge and a 1/8″ shim between the stick and the trailing spar of the tailplane for the plane with the one hole bearing.  This gives 0 downthrust, 5.7 wing incidence, 0 tailplane incidence.  The paper is under the tailplane, so it has some effective negative incidence, and it is in the downwash of the wing.
 
Dennydart II 001.JPG
I am flying in the street in front of the house, so I used the 8 1/2 loop of 3/32″ motor.  I worked up to 200 turns.  Steep climb, short cruise at 35-40 feet, motor goes slack, steep descent.
 
Dennydart II 005.JPG
 
Dennydart II 006.JPG
 
The wing mount tilted the wing and it needed some right rudder to overcome too tight a left turn and banking too steeply to climb.  I was able to straighten it by pulling the rubber bands on one side.  I have straightened the wing mounting to the shim and added 1/16″ x 1/4″ x 5/8″ balsa plates to either side of the wing shim.  They extend down across the sides of the stick and maintain the orientation of the wings.  I will not have time today to try a better motor.  Wind is already too much for safe flying in the local park.
 
The steep climb made me wonder if the wing incidence might be too much.  It levels off well, though, so maybe it is just that this motor is too powerful for a gradual climb.  I will try the 17″ loop of 0.083″ before I try reducing the wing incidence.  Maybe the tailplane could be reversed or incidence adjusted.  The wing is already pretty far back.
 
Gary

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