Glider Rider (oz11068)

About this Plan

Glider Rider. Glider carrier, launch cradle.

Note this is not a plan for an airframe. This is a plan showing the construction of a glider-carrying cradle to fit onto an existing airframe.

Quote: "Glider Rider, by Jim Bigley and the Bitterroot R/C Club.

A little over a year ago our small club began to get more involved in sailplanes. The slow graceful flying led to many hours of enjoyment, but we began to tire of our launching method.

The high start launching technique works pretty well, but the more we used a high start the more we disliked running after the chute. Besides, getting more than one glider in the air at one time was difficult on days when lift was light. We tried motor pods, but came up against numerous problems, and finally discarded that idea. We were running out of options.

Having seen a couple of glider launching planes in the various magazines the last several years, we decided to give that launching method a try. Unfortunately, we could not find any detailed information on the design and implementation of a powered glider carrying mother plane. We designed a system on our own, and everything has worked out better than we had hoped.

Our system works 100% of the time, is simple, and will work with any sailplane up to Standard class. I see no reason why this design wouldn't work with Unlimited class sailplanes if you scaled up the launching platform and used a larger mother plane. The beauty of our system is that the launching altitude can be as high as you want. Now launching several sailplanes on no lift days is easy to do. Gone are the days of running after the chute, changing line direction to match the wind, or any of those labor intensive routines.

The mother plane we use is a Senior Falcon modified with a bolt-on wing and slightly enlarged rudder. There are several suitable planes on the market, but I would recommend a shoulder or high wing trainer type with a Schnuerle 40-60. Should you use any other mother plane, modify the wing saddle on the glider launching platform to match.

Our system is designed with the glider wing and the mother plane's wing at the same incidence with a 7 in separation between the two wings. The CGs are lined up at the same vertical line when the sailplane is loaded. The drawings and pictures should give you enough information to build your own glider launcher.

Flying the loaded mother plane requires the use of coordinated rudder and ailerons while loaded and under full power with an empty launching platform. I guess the launcher disturbs the airflow enough to require coordinated controls. At 1/2 or lower throttle, the Falcon flies near normal with a bare launcher, so landings are easy to do without worrying about coordinated controls. The radio we are using does not have mixing, so to make the plane easier to fly for other members of the club, we changed the roll control on the Falcon to rudder instead of ailerons. This change has worked out quite well as the Falcon flies fine with rudder.

As soon as the loaded Falcon is off the ground, we trim for the best climb. That way when the two planes are too high to see pitch accurately we just worry about turns as pitch is already trimmed in. Ordinarily the glider pilot doesn't need to do any controlling until after release, but should you fly through a strong ground thermal or air pocket, the glider pilot should be ready to assist in getting pitch and roll stabilized. Excess speed could cause some problems so keep the mother plane climbing while loaded to keep the speed down, and keep the turns flat with as little altitude loss as possible.

We were concerned about overstressing the sailplane's wings with too much airspeed, but we have found you can safely fly the loaded combination as fast as the sailplane can fly on its own. Steep climbouts don't seem to affect the sailplane's wings either.

Once altitude has been attained, we come back to idle on the mother plane, feed in lots of up elevator to get minimum airspeed, then hit the release. The sailplane will simply and beautifully float off in an upwards direction with its elevator at neutral. Very impressive. If something happens and you need to unload the sailplane at a higher airspeed than normal, the only thing that will happen is the sailplane will balloon up possibly into a loop, nothing serious."

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