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Thread Number: 107
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Original Message
"More prop talk! More prop questions."
Posted by grant4ever on 07-10-03 at 21:40z
Group,

Ok, flew again today. This time I payed attention to a few things.

For starters, a full throttle climb requires me to hold 85 mph indicated to not exceed 2700 rpm.

Straight and level flight is 1/3 to 3/8 throttle to maintain 2700 rpm.

Full throttle will get me 3100 to 3150 rpm.

I think that I may be underpropped. I think that with the engines ability to overrev so easily that I am flying around with the throttle way back and not making any real HP. Of course my gas mileage is great but I would rather get more performance out of the Pitts! What do you think?

Gus

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Messages in this discussion
"RE: More prop talk! More prop questions."
Posted by KendalSimpson on 07-11-03 at 19:22z
Yea Gus I think you hit the nail on the head. Level flight at full throttle should not give you red-line or over with a metal fixed pitch prop. I couldn't recomend what prop pitch/length you need but definately one that is more course or longer that what your turning now.

Kendal Simpson
www.littletootaerobatics.com

"RE: More prop talk! More prop questions."
Posted by Patty_Wagstaff on 07-12-03 at 14:30z
Hey Gus

I presume you're flying a Pitts? The numbers you give don't sound that out of line to me. I'd check with the Prop experts - not sure who makes your prop - and ask them what they think too. But, from first glance at your e-mail the numbers sound good.

Patty

"RE: More prop talk! More prop questions."
Posted by grant4ever on 07-12-03 at 23:08z
Patty,

Yes, its a Pitts S1S. I'm asking as many people as possible. I am looking for real world experience as well as what the manufacturers have to say.

I am convinced though that I'm turning too many rpm too easily. To keep my rpm down to 2700 I have the throttle retarded so far that I am not making any real HP.

I think that a higher pitched prop will let me carry more power and still keep the revs down to 2700 rpm.

I got to say, I flew a couple of loops the other day at full throttle (3100 rpm) and they were huge. They felt better too.

I guess the bottom line is that it would just be nice to go to full throttle and get 27 to 2900 rpm while making the full 180 hp that I have bolted on up front.

Gus