Midget (oz11471)

About this Plan

Midget. Radio control glider model.

Quote: "How about a sailplane and hi-start for about $10.00? The Midget is the answer. Spanning 50 inches and weighing in at 8 ounces, it's a relaxing joy for after work flying at a local schoolyard. Midget, by Randy Wrisley.

Midget is a small sailplane. How small is it? Well, it's so small you can fly it just about anywhere! That schoolyard or public park close to home becomes your private flying site. No more gas guzzling drive to and from the club flying field. After dinner, just stroll down to the park and fly up a storm. The crankiest neighbor can't complain about the noise, cause there isn't any! No glow fuel mess or spinning prop either.

Small means less expensive too. When was the last time you spent around 10 bucks fora model, including the powerplant? Midget's 'powerplant' is a simple homemade hi-start. 50 ft of Sig 1/4 in flat rubber is tied to 150 ft of 6 lb test nylon fishing line. A screwdriver is used fora stake, and a paper clip for a ring. 3 ft of crepe paper makes a dandy streamer.

I have to give credit to my friend Randy Heydon for the hi-start idea. He not only made up the first one, but also ate the oatmeal which used to occupy the box the hi-start now resides in!

Midget climbs swiftly to the top of the line and turns in consistent 3 minute flights. She also thermals easily but goes out of sight fast. For this reason it's best to stay over the field. It's no fun to retrieve your Midget from the neighbor's pool because you got too low on final!

The prototype uses a Cannon super-mini radio controlling rudder and elevator. I'm sure an Ace single channel unit could be used too. Just increase the decalage and move the CG up a bit. My Midget weighs 8 oz ready to fly. I have flown it ballasted up to 10 oz, with little loss of performance. Remember, the lighter it is, the better it flies.

Now for the best part. In addition to all of the above, Midget is also a snap to build! Here's how:

CONSTRUCTION Fuselage: Cut the sides from soft balsa and the formers from hard 3/32 balsa. Cement the 1/8 x 1/8 balsa stiffeners to the sides and mark the former locations. Glue the tail together and install F-1. When dry, cement the rest of the formers in. Plank the bottom with hard 1/16 balsa, applied cross grain. The 1/8 dowel pushrods should be fit in place before you plank the top aft end of the fuselage. Plank the nose with some more 1/16 balsa and make the hatch from the same stuff. Cement a block to F-1. Carve it to shape and sand the rest of the structure smooth.

Epoxy the 1/4 x 1/2 in spruce tow hook mounting block in place as shown on the plan. Drill two holes in it at the locations shown in the top view. Bend the top of the hook, push it through the holes and Hot Stuff it. Now bend the bottom of the hook to shape. You can install the 1/8 dowels now or after covering.

Wing: Pin the LE and TE into place. Do the same with the bottom spars noting which is spruce and which is balsa. Use a template and cut twenty-eight W1 ribs and six W2 ribs from light 1/16 balsa.

Cement the center section bottom planking in place. Fit the center section ribs next. Angle the two center ribs out about 1/32. Cement the rest of the ribs in, excepting the ones over the polyhedral joints. The tip ribs have their aft ends cut down to make them shorter. Glue the 3/32 square strips to the TE between the ribs and allow the wing to dry on the board overnight.

Cut the three polyhedral braces from 1/32 plywood. Raise each tip 2 off the board and cement the tip braces in their places! When dry, raise one of the center panels 3/4 and install the final brace. Cement the last two ribs in over the poly breaks. At this point you can add the top spars and plank the rest of the center section. Now glue the tips in place.

With a sharp X-Acto, a sanding block, and a little patience, carve the aft end of the tip ribs down to the TE. You might as well sand the LE to shape while you're at it. Cover the wing with lightweight plastic film and crank about 1/4 in of washout into each tip.

Tail Group: All the surfaces are made from medium 3132 balsa. The elevator joiner is bent from 1/32 music wire. The control horns are bits of 1/32 plywood. They are Hot Stuffed into slots cut in the control surfaces. Sand the outside edges round and cover before assembly.

Assembly: Cement the stabilizer to the fuselage. Attach the elevator to the stab using good old sewing thread hinges. Glue the vertical fin in and hinge the rudder in a like manner. Don't forget to install the sub-rudder. Stick the servos in with foam tape. Hook up the pushrods and try the controls. Remember the whole system was designed to move the controls of an 8 oz glider. It is light, and there is some flexing. Once you have installed the receiver and battery pack with respect to the CG, you can control a lot of the flexing with some foam-rubber used as packing.

Mount the switch in a convenient spot and charge up the batteries. Make up your mini hi-start as outlined at the beginning of the article, and you are all done!

Flying: Run down to the park and hand chuck your Midget a few times to check the glide. The surfaces are set at 0°-0° so you'll need some up trim. To penetrate better, or drop out of that boomer, just take out the trim.

Midget goes up on her hi-start like she was on rails. To me, a hi-start launch is sort of like a tail dragger taking off. Whatever you find is necessary to do with the rudder is best done in small amounts! Go real easy at first, and don't use any elevator control during the climb-out. Once the model reaches the top, turn away from the stake and feed in a slight amount of up elevator to pop off the line.

In lift, you can stay up as long as your eyesight holds out. If you don't find any lift, practice 2 minute precision flights, catching the model instead of landing in a spot. I hope you have a simply great time flying your simple, little sailplane."

Midget, RCM plans, January 1980.

Direct submission to Outerzone.

Supplementary file notes

Article pages, thanks to RFJ.

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