Monday, November 20, 2017

Adventures in Electric Control Line

The first really successful model airplanes I built were control line model airplanes powered by .049 glow engines. My two best friends in the neighborhood flew control line also, I can remember saving allowance for glow fuel and 1 ½ volt dry cells. I still have a .35 powered control line a Goldberg Buster in flyable shape; I should try flying it again. 

Prop Buster CL Electrified

Before Covering

My new interest to try control line came from a desire to try it again and see if I can do better and also the fact the airplanes can be flown in smaller locations. Now with the availability of electric systems for control line, I thought I could fly it in places that glow engines were not allowed. It seems that many of the people who fly free flight model airplanes, also fly control line also. The other thing I had ran across the Shugemery channel on Youtube and was impressed by his passion for control line model airplanes.

Electric Motor has Rear Bearing Mounted in the Plane

ESC and Controller

In my basement stash of model kits I happened to have to control line kits I purchased at a hobby shop before it closed. One was a ½ A size but the other was a Ringmaster Jr, I thought first I would build the Ringmaster Jr as electric but then remember many years ago I had started on a .15 size plane the Prop Buster from MAN plans. The Prop Buster plans were on the back of a RC plane plan for the Oily Bird that I had built. 

My Old EZ Just Handle, I have New Plywood Handle Also

My big worry with electric control line was what it the plane crashed, what will stop the motor from stalling and burning out a component?  The system I purchased from RSM Distribution should automatically shutdown if too large a load is encountered. Slowly I finished the Prop Buster and a week ago I was going to fly it but realized the ends were not on the control line cable I had. It was a rather calm day so I flew my electric RC glider instead and ordered lines with the ends on, I will finish putting the ends on the other cable later.

Takeoff Blacktop, Fly Over Grass

It is getting to the time of year in Minnesota that many more reasonable people quit flying model airplanes outdoors but not me. It was rather windy on Sunday but the sun was out and it was almost 40 degrees, I was going to make one flight and call that enough. The wind worried me but I thought maybe the hills would block it some. I had planned out a spot it could take off from blacktop and then fly over grass.

Crash Scene

I attached the lines, checked the controls and pushed the button to start the electric motor sequence. It runs for a couple seconds to show that it is active, waits 20 seconds, and then runs for 2 minutes. This is the default settings which can be changed. I was scared something would go wrong but I had to go through with it. The last time I flew a large control line I was a teenager but it was rather like controlling a RC plane but only in two dimensions.

With me at the handle, the plane takes off, wow it is really flying. Pretty soon it is getting really wild, the plane is bouncing up and down and the lines wanted to go slack when upwind. Right away I am thinking I really wish I could cut the throttle. It is bouncing up and down but I managed to miss the ground through maybe 6 laps. The line would slack and then jerk as it got closer to downwind leg. I was thinking should I try to dump it when it was close to the ground or try to fly for the 2 minutes.

Despite my efforts to keep it airborne, it hit the ground while the lines were slack. Impact was pretty level and did not have excessive speed but still it did some damage. Vertical fin and stab were knocked off, a dowel that was a stop for landing gear broke, there was a crack in the fuselage, and the propeller was broken.  When I got home I noticed a rip in the covering on the bottom. Most of it is fixed and more props are on order.

Next time I will wait for less wind and be checking out the control better to make sure there are no binds.

Bill Kuhl

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1 comment:

  1. I control the throttle using RC, hanging the transmitter on my waist. This way, I can start the motor from the center of the circle, adjust the throttle in flight, and kill the throttle anytime.

    Assign "throttle hold" to a switch on the transmitter, so that you won't start the motor by bumping on the throttle stick accidentally.

    Not a purist approach, but quite convenient.