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As a small boy, my father
delighted in making small wooden boats for me. They were very simple.
They were made from a plank of wood, sawn into a vee-shaped front end
and slightly rounded back end. The inside was painstakingly carved out
with a wood gouge. On the under side, a small curtain hook was screwed
in at the front end as the anchor for a rubber band. At the back end was
a masterful piece of engineering. A glass bead sat snuggly in the eye of
a closed hook, next to which was a smaller bead acting as a bearing.
Through both was passed a piece of wire, the end of which was hooked to
take the other end of the rubber band. The opposite end of the wire was
passed through a small hand-carved propeller and the end of the wire
turned back on itself to pierce the propeller wood locking both securely
together. By carefully winding up the propeller it was possible to store
sufficient energy to propel the craft from one end of our bath tub to
the other. |
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The fact that it was necessary
to fill the bath almost to the top for the small boy to reach over and
launch the craft; that the small boy got soaking wet, possibly accounting
for a subsequent severe cold; and the bathroom floor awash with water caused
the floor tiles to curl up at the edges; were all small environmental
penalties for the satisfaction of the small boy (me).
When I grew older, I determined
on a more advanced project. It would be at least twice as large, and store
much more energy. It would also fly rather than float. It would be modeled
on the pre-war high-wing Lysander, an elegant single-engine craft of its day.
To this end, a large propeller was purchased, complete with a free-wheeling
trip, so that the propeller would not impeded flight once the energy ran
out. Three heavy-duty 12 inch long rubber bands were also purchased to store
the propulsion energy. Balsa wood, the recommended light-weight structural
material of the day would obviously not be strong enough to resist the force
of the wound up bands.
Bamboo shoots were therefore
carefully split into strips and formed the main structural members, and so
the fuselage and wings were built. The wings and tail had adjustable
ailerons and, for advanced control, stability was maintained by mechanical
linkage to small lead-weighted pendulums mounted amidships in the body. The
whole was covered with tissue paper, painted and painstakingly covered with
shellac for strength. Came the day for launch. The weather was sunny and
mild. To give the aircraft a head start, it was launched from the top of the
chicken breeder house (we lived on a chicken farm at the time.) The rubber
bands were twisted to their maximum, the craft held high in the air - and
launched into space.
It seems that the propeller was
not quite matched to the craft, or maybe there was some other aeronautical
inconsistency. At any rate the craft traveled a few yards and promptly
descended in an ignominious nose dive. Upon hitting the ground, structural
failure resulted in all the rubber band energy being released with the body
ending up as an unrecognizable twisted mess. At that point my flying model
aircraft days were over for ever.
The moral of this story?
Threefold. Projects come in all shapes and sizes. To be successful, you must
get the concept right and, thirdly, don't be overly ambitious!
Copyright© 2006 Max Wideman
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