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View Full Version : Right prop, wrong prop? Wood prop, metal prop?


Gus Rasch
July 10th 03, 10:28 PM
Group,

Two different questions. Looking for your input.

#1

Flew my S1S with an O-360 180hp and swinging a metal Sensenich prop
76-56. This combination has always been easy to overspeed the engine.
On climb out at full throttle I have to maintain 85 mph indicated or
it will exceed 2700 rpm. In cruise it only takes 1/3 to 1/2 throttle
to maintain 2700 rpm in level flight. At full throttle it will hit
3100 rpm. To me it seems like it's underproped. I am thinking of
going to something with more pitch, like a -58 or -60. What do you
think?

#2

Since I am thinking of a prop change I have also considered going to
wood. Specifically a "Performance Propeller" wood two bladed. I have
heard all the advantages/disadvantages over the years and just
wondered if anybody has some real world experience with their pitts or
similar.

Many thanks for input/feedback.

Gus

JOM
February 14th 08, 11:18 PM
I have flown behind both metal and wood props, however they were on lower horsepower engines. The metal props were all more effecient. The wood props gave quicker engine response. If you are flying acrobatics you may not want to have prop pitch too course since it will hurt your climb performance.

You should also check you tachometer. They are often wrong. It would be a shame to find out after spending money on the prop.

In the type certificate for your plane there should be a spec listing the static rpm. You should check this and see how your plane compares. If you have a homebuilt, a type cert. for a comparable installation should give you a idea if you are ok.

John

Group,

Two different questions. Looking for your input.

#1

Flew my S1S with an O-360 180hp and swinging a metal Sensenich prop
76-56. This combination has always been easy to overspeed the engine.
On climb out at full throttle I have to maintain 85 mph indicated or
it will exceed 2700 rpm. In cruise it only takes 1/3 to 1/2 throttle
to maintain 2700 rpm in level flight. At full throttle it will hit
3100 rpm. To me it seems like it's underproped. I am thinking of
going to something with more pitch, like a -58 or -60. What do you
think?

#2

Since I am thinking of a prop change I have also considered going to
wood. Specifically a "Performance Propeller" wood two bladed. I have
heard all the advantages/disadvantages over the years and just
wondered if anybody has some real world experience with their pitts or
similar.

Many thanks for input/feedback.

Gus

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