We had one of these when we were kids.
Dad built one for us after seeing one aeons ago in a theme
park in Victoria somewhere. I reckon it was a two bladed
Chinook.
I made this one a few years ago for my son modelled on
Dad's mechanism.
But my boy was a bit too young to fly it well.
So I had to refine it and test it myself for several years eh
Well we got it out this morning and dusted it off and he can
fly it very well now.
The body of the chopper is a wind up toy scavenged for it's shell only.
The motor/reduction is from an RC car. You need reduction for the
good speed range of the blades to lift well.
The pole has a set of circular copper tracks on a printed circuit board
stuck underneath a ring of plywood.
This connects the motor and flashing LEDS to the chopper as it rotates
around the pole.
Forward and reverse flight is achieved by tilting the chopper body
slightly forward and reverse to alter the thrust line.
This tilt is done with a planetary reduction kit from Tamiya / DSE.
Finally, a shmick control panel with one of his Scaletrix speed controls
does the throttle and tilt with some fake instruments
Steve