Fig.1
Fig. 1A
Fig. 2
Fig. 3
Fig. 4
Fig. 5
horsepower is equal to 112 watts. Sorry, but I just couldn’t put that little power in, so in- stead I chose a contra-rotating motor setup which produces 300 watts of power, with a 3-cell Li-Po battery. I gave SkySport nearly three times too
much horsepower, (hoping you will forgive me for that), and I realize the top speed will cer- tainly exceed 17.5 mph. After all, with a name like SkySport, the model should be capable of some aerobatics, and some decent speed. The reason I chose a contra-rotating pow- erplant was to eliminate the normal torque effect that a single prop generates, that must be countered with rudder for takeoff, and a plane that really wouldn’t fly without a small amount of crab during flight. Taking off a normal single engine tail dragger air- craft exaggerates the torque effect even more, and requires a lot of rudder to keep straight. So with contra-rotating props, SkySport would be easy to take off with little or no
FLYING MODELS
rudder. If I built it right, it should fly straight, and that idea was pretty exciting! A friend of mine found a great little LED light set, which he installed on his R/C truck, and I decided to add it to this plane. The lights are optional, mainly intended for display, probably shouldn’t use them past dusk when flying. Let’s start building.
At the bench Tail feathers: Before we pin the tail
pieces to the flat building surface (I used a piece of drywall), several 3⁄16-inch balsa parts will need to be cut out. You will probably just want to photocopy that part of the plans, and then glue stick the photocopy to the balsa, and cut the pieces out using a scroll saw. When you have done that, lay a piece of wax paper over the plans, and pin and glue everything shown in Fig. 1, and 1A. While those pieces are drying, cut out the
rest of the parts for SkySport. You will note that many parts are pairs, so glue one piece
of balsa on top of the other (be careful to glue them only in corners, so when you cut them out, they will not be stuck together). When the tail structure has dried, remove it from the wax paper, and sand the outside edges to a nice radius. Also, this is a good time to slot for the hinges, and test fit the hinges in place.
Wheel pants, and landing gear: It
takes four parts to make the wheel pants. First of all, glue the small oak piece with the hole to the inner side piece. Make sure it is exactly flush. When that has dried, then epoxy a 6-32 nut to the oak piece. It can be held in place by putting a 6-32 screw though the hole, as shown in Fig. 2. Do not get any epoxy on the threads of the nut. When that has set, glue the 5⁄8-inch thick
balsa piece to the inner and outer side pieces. Make sure you are creating a left and a right part. When that has dried, sand the whole wheel pant to a nice rounded shape. The aluminum landing gear struts should
19
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68