Martin.  As you may remember I had a number of Drones starting with S/N 144. Which was given to me by one of my lawn cutting customers when I was 12 or 13?  I can’t remember his name but he was probably in his late 30’s at the time and had a garage full of model planes and engines. After this I owned a number of Olson’s including a .19, a number of .23’s, and a 60. About 25 years ago I came across an old Olson .23 complete with coil and condenser, and an engine mount. It ran beautifully.  I tried to get my sons interested in model planes, but to no avail. This engine along with several others has disappeared over the years.   

If I recall correctly, Drone put out a number of planes kits including one called a Secret Weapon. I built this plane, but shortened the fuselage by about 4 inches, and flew it at several U/C events. This was the first plane that I had, that could do vertical figure 8’s.

I used to use a 10x10 or a 10x12 prop.  I was told that Drones should not be allowed to run at over 5k rpm if you wanted them to last.

Some people thought that Drones were hard to start, but if I remember correctly (It is about 65 years ago) I would start a new Drone by opening the needle valve about a quarter turn. Prime the engine and give it a couple of flips. I would start and run for a few seconds and quit. I would open the needle valve a few clicks and start the process all over again, until the engine continued to run. At this point I might turn the valve up or down until the engine ran smoothly. From this point on I tried never to touch the needle valve, and I would fuel up the tank prime the engine, and after a few flips of the prop I was in business. I never found Drones to be hard to start.    

Chris