I 100 percent vote with Tracy on this issue. I strongly urge people with
potentially fast planes to go with
a ratio that will give them at least 2700 at the prop at top power and speed. The
steep pitched props
churn helplessly at low forward speed, and you will be outclimbed by an
overweight buzzard that
just finished a whole cow. Save those ratios for Storch and Helio Courier
replicas. (and stationary
top speed gyros :-)  no insult intended guys - you obviously can have a lot of
fun below 100 mph too)
- Vance

Hey who needs to get off the ground in 500 feet? Plenty of airports
around with 5000 feet. Look at Perry Mick! He is having fun and talk
about no thrust down low! Sheesss! I would gladly trade another
1500 feet of runway for another 25 mph top end.

Well Vance if you had designed in longer landing gear on the silly Kis Cruiser I could
have used a larger diameter prop instead of just more pitch :-)

BTW I dropped off a couple of carbon fiber blades for you to look at
over at Rich's today.

Paul - you know that you cannot trade diameter and pitch back and forth - if you are
turning slow
you will need lots of pitch regardless of diameter - the Cruiser will spin a prop diameter
that is just about "just right" as the fabled Goldylocks said of the porridge.

Yes but the bigger prop will be more efficient as you have told me yourself
many times in the past :-)

The prop blades looked pretty neat - good looking planform, tho a bit thick. How will the
smooth cylindrical shank be retained in the hub? The tear drop wrap arounds are pretty
elegant,
but I suspect the fibers stop fairly soon out the blade. The bias BID being stopped at
both
the leading and trailing edge will reduce the potential torsional stiffness, but maybe
that is intended.
What power and rpm are they designed for? - Vance

It was just a prototype. We planned on drilling holes through the tear drops
and using large diameter pins. The guy that made it screwed up :-)
It was designed for a 100 HP Cont. O-200 on a Dragonfly with limited
prop clearance.

Paul Lamar
 
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