Climb prop question

[Milo Dyke]

Hello all,

Just finishing my 46' BC12D with a C90-14. I have a McCauley 71/46. Just wondering what I can pitch this down to, so i can get best performance? Happy Thanksgiving!

Milo

[flyguy]

Re: Climb prop question

Pitch giveth and pitch taketh away. Do you want cruise or climb? I have a 85 with a 7146. Pretty good all around. I suppose it depends on how much tighter the 90 winds to get the extra 5. There are some pretty long discussions here on props for different engines, look around.
DC

[Milo Dyke]

Re: Climb prop question

Right now ... static rpm i get 2300.... level flight full throttle 2450.... tach is good...looking for best short field performance with this prop.... was thinking a 43 pitch? I just had the prop overhauled and told the guy to repitch it to a climb prop for 90 horse taylorcraft and it came back as the same pitch. Thanks again.

Milo

[VictorBravo]

Re: Climb prop question

If you only have a 150 RPM spread between static and full throttle in flight, it seems to me you have way too much prop or some drag issue on the airplane?

Try pitching it down to 42 or 43 as a first guess.

[Pearson]

Re: Climb prop question

I thought the whole advantage of a C90 was more torque at lower RPMs. If you went to higher RPMs you would actually lose power. If you could get a graph of the torque curve, it would give you an RPM to shoot for.

[astjp2]

Re: Climb prop question

Climb=lenght of prop
RPM=pitch

You can goto a M74CK-0-43 and it will climb like an angel going to Heaven....It is approved on the prop TCDS for a C-90. Sell your prop you have and get one that will do what you want. Tim

[gcgilpin]

Re: Climb prop question

7142 will give you excellent take-off & climb performance. Relatively common prop on C90s.

[Milo Dyke]

Re: Climb prop question

Thanks for the information guys...when i get the plane finished i will post some pictures... happy holidays

milo

[Doc]

Re: Climb prop question

Just a reminder...I have a yellow tagged Kliptip 1B90 7138 that could be repitched up if desired. Jordan propeller is San Antonio charges about $400-450 to overhaul to your specs. Doc