Which Propeller?

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8434
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Which Propeller?

Post by 8434 »

Hi Folks,

My prop is up for inspection next year and I have been contemplating getting it re-pitched from 52 to 50 to improve STOL performance. Its a McCauley CM7152. I started doing some research and found there are other options but none that I could find with STCs, so what is everyone else running? Has anyone put a Catto prop on? What about ground adjustable?

Marshall
klyde sessna
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Re: Which Propeller?

Post by klyde sessna »

A 7148 is standard. A 7150 is cruise. You are probably way overpitched.
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Re: Which Propeller?

Post by klyde sessna »

A 7146 is proper pitch for a climb prop..
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6643
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Re: Which Propeller?

Post by 6643 »

"A 7148 is standard. A 7150 is cruise."
"A 7146 is proper pitch for a climb prop.."

These statements are true if you have a C85 installed. If you have a C90, the 7152 is the "standard" prop. 7150 would be considered a climb prop.

Look at the type certificate for a list of approved props for your engine. Choose a pitch that puts your static RPM near the upper limit for best climb performance. There are a few STCs out there, but not many, that I'm aware of.
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Re: Which Propeller?

Post by 6795 »

I have the C-85/O-200 Crank conversion swinging a Sensenich 76AK-2-44 prop.
Works well!
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Re: Which Propeller?

Post by 6643 »

Moved to Technical Discussion.
1125
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Re: Which Propeller?

Post by 1125 »

Did the overhaul with Millineum cylinders, ASS crankshaft mod and found the 71- 46 pitch would overspeed upon takeoff. Took it to Maxwell in Minneapolis, discussed the issue. They repitched it to 71-48. The ground run RPM (per type certificate data sheet) was right on, the airplane is a good performer. Remember to read the TC data sheet, there is a lot of good info for the aircraft airworthiness in there. It's all in the reference manual our club members put together years ago. Thanks to them, we have a great resource to keep our airplanes flying.
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Re: Which Propeller?

Post by 8475 »

1125 wrote: Tue Apr 14, 2020 9:04 pm Did the overhaul with Millineum cylinders, ASS crankshaft mod and found the 71- 46 pitch would overspeed upon takeoff. Took it to Maxwell in Minneapolis, discussed the issue. They repitched it to 71-48. The ground run RPM (per type certificate data sheet) was right on, the airplane is a good performer. Remember to read the TC data sheet, there is a lot of good info for the aircraft airworthiness in there. It's all in the reference manual our club members put together years ago. Thanks to them, we have a great resource to keep our airplanes flying.
Where can I find a copy of this alleged reference manual?
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Re: Which Propeller?

Post by 2066 »

8475 wrote: Sat Apr 25, 2020 9:03 am
1125 wrote: Tue Apr 14, 2020 9:04 pm Did the overhaul with Millineum cylinders, ASS crankshaft mod and found the 71- 46 pitch would overspeed upon takeoff. Took it to Maxwell in Minneapolis, discussed the issue. They repitched it to 71-48. The ground run RPM (per type certificate data sheet) was right on, the airplane is a good performer. Remember to read the TC data sheet, there is a lot of good info for the aircraft airworthiness in there. It's all in the reference manual our club members put together years ago. Thanks to them, we have a great resource to keep our airplanes flying.
Where can I find a copy of this alleged reference manual?
Click "Store" (above), then "Cessna 120-140 Marketplace" -- "Reference..." + order. Mac
8475
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Re: Which Propeller?

Post by 8475 »

2066 wrote: Sat Apr 25, 2020 9:29 am
8475 wrote: Sat Apr 25, 2020 9:03 am
1125 wrote: Tue Apr 14, 2020 9:04 pm Did the overhaul with Millineum cylinders, ASS crankshaft mod and found the 71- 46 pitch would overspeed upon takeoff. Took it to Maxwell in Minneapolis, discussed the issue. They repitched it to 71-48. The ground run RPM (per type certificate data sheet) was right on, the airplane is a good performer. Remember to read the TC data sheet, there is a lot of good info for the aircraft airworthiness in there. It's all in the reference manual our club members put together years ago. Thanks to them, we have a great resource to keep our airplanes flying.
Where can I find a copy of this alleged reference manual?
Click "Store" (above), then "Cessna 120-140 Marketplace" -- "Reference..." + order. Mac
Mac, thanks. I tried to purchase the book, but the checkout code is behaving oddly. Unable to view the qty in the qty box and when I go to check out, the site just hangs. I've tried both Firefox and Edge.
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