The big question over past years was whether a prop could be re-pitched
by cutting the blades off the hub, setting them to the desired angle,
and re-gluing.
This would seem more accurate and reliable than the "accepted" method of
heating the prop bases and twisting them, and not break the spirit of
the rule. One might also conceive of a tubular splint that would let the
pitch be adjusted for experimental flights, then glued to a fixed
"best" position for the contest. In fact there are Ikara prop kits that
are designed for this, but they come in parts rather than a single piece.
The "single piece" requirement would seem to preclude any VP gizmos, as
a vp prop is a multipiece assembly, if it has springs or bearings or
swivels or hinges.
The single piece rule dates back to the day when they required a single
piece injection molded prop, which made sense from a rules semantics
standpoint. One cast component. Then scraping was allowed- that was
controversial in its day. The Ikaras are made up of a hub with glued on
blades, and could be argued to be three piece props, though they are
glued or welded together. Nonetheless, they became "defacto" accepted
and allowed great improvements in buildability and performance.
"manufactured" is another loose term. IF anyone on this list decided to
manufacture a few hundred (or tens or 1000s?) of props using the allowed
materials and make them available to the public, certainly that would
qualify. (hint) Careful materials choices and blade design could
conceivably be used to create a self flaring prop that came pretty close
to the best VP performance...
I recall my amazement when I learned that Ikaras were accepted. I saw
them the year before and concluded immediately that they were not "one
piece" and so would not be acceptable. But they eliminated scraping, and
were such an improvement that anyone with any free flight experience
could not bear to force the kids back to those old plastic clunkers!
Received on Sat Sep 29 2007 - 07:56:33 CEST
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:45 CET