Doug,
Nice Job.
About the most clever use of this idea that I've seen is from a fellow
that has to keep a grass runway mowed for his light plane. He ran a
cable down the center of the runway. Attached to the cable was a gear
box. When a crank on the gear box is turned the gear box slowly walks
its way down the long cable. This fellow then used a setup like yours,
with a long cable attached at one end to the gear box crank, and
attached at the other to a 21" wide self propelled gas mower. He starts
the mower and it mows circles about 40 feet wide, each one a bit further
down the runway until the whole runway is mowed. Next time he reverses
the direction of the mower and mows the other way up the runway. This
was written up in a publication called "Farm Show" about 4 years ago.
I once heard a tale of an old bush pilot that had some engine trouble and
had to make a forced landing in a small clearing. He was lucky and made
a good landing. In about 15 minutes he realized two things. One, the
engine problem was easy to fix, and two the clearing was too small to
take off from. As the tale goes the fellow taxied to a spot that had a
tree in the middle and a path around the outside. He tied a rope to the
tree and to the landing gear on his Piper Cub. He then taxied in a circle
determined by the length of the rope until he had found a pretty smooth
unobstructed circle. Full power, and pretty soon he was flying in a circle
around the tree. He reach out and cut the rope at the landing gear and
was on his merry way. I don't know, it may be a rural legend, but I guess
it could happen. The fellow that is supposed to have done this was a bit
crazy, like flying through the open door of a big barn, etc. so maybe it
really happened.
Anyway, thanks for showing us your version of this idea...
Ken Reed