How to use your R/C 'copter to lift a glider up high and launch it!
Step 1: Print the Glider Template
Download, then print this attached template on two sheets of A4 or 8.5"*11" paper.
NOTE: do not fly on a breezy day, and make sure to fly straight upwards then release glider, avoid all around the place. optimally use a large field or park!
Step 2: Acquire Parts Needed:
Acquire foam board, hack saw, tape, hot glue and glue gun, a knife for cutting the foam, and a 'copter that is capable of lifting at least 32 grams.
You'll want to use foam board that does not have glossy coating on it. We used foam board from Dollar Tree.
Step 3: Cut the Foam Board According to the Template.
Lay out the two sheets of printed template on top of the foam board, and cut through. The two sheets of paper should form one continuous wing, not two wings.
Step 4: Cut One Soda Bottle at the Neck.
Step 5: Preheat the Hot Glue Gun by Plugging It in to the Wall.
Step 6: Glue the Bottle Neck End to the Glider
Glue on bottle neck to the nose of the glider, at the exact front center, with the threads facing forwards.
Step 7: Brace It With a 2nd Bottle Cap
Glue the second bottle cap to the the plane and then to the bottle piece sturdily in order to prevent it from snapping!
Our first design did not use this brace, and the connection snapped and caused our quadcopter to lose control and drop from very high up! Luckily, one of us caught it. It nearly landed in a creek!
Step 8: Glue Another Bottle Cap to the 'copter
Glue a bottle cap to the belly of the 'copter, at the exact center of gravity or center of thrust. If your drone has a landing gear in the way of freely rotating the glider, simply glue a small box underneath to add a space to mount the cap on to.
Step 9: Test It Out!
In a flying space with zero wind, screw the glider onto the 'copter loosely. Then fly the 'copter carrying the glider straight upwards as high as you are comfortable with! Here in the USA, it is illegal to fly higher than 400 feet with a hobby UAS, and if the copter plus payload total is more than 250 grams, it needs to be registered with the FAA. So make sure to follow your local laws. To release the glider, rotate the 'copter counterclockwise! On my mode 2 remote controller transmitter, this is done by moving the left stick to the left.
Step 10: Backstory
We had a day with nothing particular to do, so naturally we looked around the workshop to see what scrap resources we had. There was scrap foam board from my brother's latest R/C plane, and there was my new R/C quadcopter. Idea! Sky tow a foam board glider high up with the quadcopter, and then drop it!
We realized our main constraint was the lack of extra channels on the toy grade quadcopter, so we could not use a servo motor as the release mechanism. A remote control WiFi module based system using an app such as Blynk would require a constant, long range internet connection in the flying field, which we do not have.
Back to the drawing board it was.
Somehow the movement of the quadcopter itself would have to act as the release mechanism. The next thought was to use a less frequently used movement of the quadcopter to release the glider. We figured the least common movement of the quad when flying straight upwards is rotation. We proceeded to do research on the web to find more ideas. We watched a video where a barrel mounted on a drone was used to drop toy parachutes. My quad's maximum rotation speed was too slow for that! A barrel would be too heavy and too large for our quadcopter! The next video we saw was a cord system that allowed a octocopter to tow a glider diagonally like a airborne bungee launcher. Their octocopter system crashed because the glider flopped around too much from turbulence. We then knew our launcher would have to both unscrew sturdily to drop the glider, and also the glider must not block airflow from the copter propellers. So based on that, we figured the glider would have to be lifted tail up or nose up. This method gained the feature of airflow from the rotation adding resistance to the glider so that it would not like to rotate along with the quad. It would unscrew and drop!
Eureka! A loosely attached threaded bottle cap and neck would be the perfect release mechanism!
After that, the rest was simple. We assemble and tested a couple different glider styles, and settled on a simple flying wing with vertical stabilizers on the wing tips. We had a lot of fun, and we enjoyed the ideation, problem solving, assembly, and testing process. All of our neighborhood kids had fun catching the glider.
And there you have it!
If you build one, we hope you will have fun too!