This could just be silly, but how about reducing the torque the engine can
produce at lower revs, by backing off the timing and over-leaning the injection
system. Once through the problem RPM, then back to ideal power settings.
Hi
Lynn,
If it's a silly idea,
then I'm as guilty as you are for thinking about it. One thought in
particular was that it might be a vote for using a PP
engine. It will be interesting to see how well Richard's engine does with
a real prop.
Another idea was
reinforced this morning. The Hirth F30 engine on the two
place Dominator has a centrifugal clutch on it, that doesn't engage
until about 2500 rpm. Now THAT would be perfect for the single
rotor. The only downside is drag from the freewheeling prop
if the engine quit.
The idea of running with no
pitch was to eliminate blade stiffness as a part of the problem.
Understood, but don't we
know that blade stiffness IS the problem?
A friend had one of those props on his ultra-light and it touched the
chassis on run up, where the wood prop of the same diameter did not.
The Warp, and even
worse, the IVO props are flexible, and nothing's going to
change that. I saw a prop strike mark on a gyro today that
required about 5" of flex from the Warp prop, so I'm thinking this is
just normal for them. The Warp Drive is solid carbon fiber, and
bulletproof when it comes to hitting things that go into it during flight.
I consider it a must have for a pusher, since I know that it's not a matter of
if, but when something will go through it. I'll just have to give it
enough wiggle room :-)
Rusty (depitching and
playing more tomorrow)