Prop Pitch Adjustment

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Simon Handley
Posts: 9
Joined: Mon May 31, 2010 3:42 pm

Prop Pitch Adjustment

Post by Simon Handley » Tue Jun 01, 2010 6:54 pm

Wonder if anyone can offer the best advice to set up a GSC 68" wooden 3 bladed prop with Rotax 582 on Avid Speedwing? I have tried it at 10 degrees, (no go at all) 13 degrees (little better) and now at 15 degrees. The performance still does not seem good at 15 degrees with climb rate of 500ft/min and cruise speed of 50 to 60mph. The EGT's are reaching 1200 at 6000rpm. Should I coarsen the prop pitch by another degree? to work the engine harder? I believe you set the pitch up at 6200rpm on the ground which equates 6500rpm in flight. The engine is easily achieving more than 6200rpm on the ground with 15 degrees.

Or maybe I should try a different prop?

Any advice good

Many thanks

Simon

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Rod1
Posts: 567
Joined: Wed Jan 02, 2008 8:22 am
Location: Midlands

Post by Rod1 » Wed Jun 02, 2010 10:49 am

Simon,

I have no experience on your engine/airframe/prop combo but I have set up a prop without any set-up data. The first thing is to be as sure as possible that your engine is producing full power. Having done that adjust your prop to give you the book static RPM. Now do some fast taxi tests and if all is ok do a test flight. You will then have the data to decide if more tweaks are required. All of this would have to be approved by your inspector, and possibly the LAA

Rod1
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Simon Handley
Posts: 9
Joined: Mon May 31, 2010 3:42 pm

Prop Adjustment

Post by Simon Handley » Wed Jun 02, 2010 5:05 pm

Hi Rod,

Prop has been approved by the LAA and certified for plane, spoke with my LAA local inspector about changing settings as the prop pitches were OK for very short field TO but not cruise when I got the plane. He recommended I talk through with another local LAA person who has knows about these things. I have now been given the settings by another pilot who has a Kitfox with same engine, same prop type and gear box.

Thanks

Simon Handley

Simon Handley
Posts: 9
Joined: Mon May 31, 2010 3:42 pm

Prop Adjustment

Post by Simon Handley » Sat Jun 05, 2010 4:11 pm

Prop now adjusted. Turns out to be 19 degrees at 25.5" from centre line. Gives 6150 static at 22 air temp. This gave 800ft/min climb on warm day, 6mph head wind. Cruise settled down to 5000rpm at 70 mph with 20C air temp. EGTS all normal.

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