Metal Prop vs. Wood Prop

HI Larry,

I got about 2150 static and 2240 climbing at 60 MPH on a 72x42 wood
Cruise is 80-85 MPH 2150 rpm
The plane is a Champ 7AC 1945 (A-65)

The static rpm should not be under 1960 !

A metal might be a bit longer (73")

Jan Carlsson
www.jcpropellerdesign.com

A Climb prop should not turn faster then the redline with WOT during a
climb
(Vy)
A Cruise prop should not turn faster then redline with WOT at your
cruise
alt.
A Standard prop fall in between the two above!

A Cub or Champ with a A-65 or C-90 both have a 72"X42" as Standard prop
(wood) (the C-90 will be about 9 MPH faster at cruise, using 30% more
fuel)

Jan Carlsson
www.jcpropellerdesign.com



Thanks for the link, Jan. I get 2100 rpm on static runup with a 72-42
Sensenich wooden climb prop. It will easily over-rev in straight and
level
flight. Now what should I get static with a 72-44 prop? More or less?
Less, I would think. I haven't tried it on yet, but plan to just to see.
The engine has recently been rebuilt and so the old numbers, which were
lower at static, iirc, are no longer valid.