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Old 11-09-2006 | 10:05 AM
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larry@coyotenet
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From: pueblo, CO
Default Prop rpm's

Prop comparisons are always a good subject here so here goes some figures obtained last week at our flying field.
Engine--Stock g-62 with bennett muffler
Plane---T-F P-51 ARF
Altitude-5,000 feet
Temp.---55 degrees and humidity ~50%
all props tested using 87 octane gas with 40 to 1 Honda oil

Bamboola 22/8 -----6800
Zinger std 22/8------7100
Zinger std 22/6/10---7100
Zinger std 20/8/14---7100
XOAR 22/8-------7200
APC 20/10-----8500

An unscientific pull test showed that the XOAR seemed to pull best, closely followed by the Zinger 22/8 and the 20/8/14, the
Bamboola pulled worst.

Plane was flown with the Zinger 22/8 and flew quite well, good speed and pull and sounded great.
Did not fly with other props, Wanted to test XOAR but would not fit spinner cut outs. Have flown plane with a Menz 22/8, same RPM as Zinger 22/8, Seemed to pull and fly very similar. Remember , THIS IS A WARBIRD! IT DOES NOT FLY LIKE A 3D PLANE! I don't want to hear that a DA50 or a Briillili would fly better! Also, we fly at a mile high, This means we have to go down a prop size to get the RPM's into the power band, take that into consideration. Have flown the TF p-47 with same combo, and aTF Corsair with a Sachs 4.2.
I think that given all factors the APC would probably fly these planes the best but I am leary about using them on the Sachs. I do know that the G-62 turned the APC the most effortlessly. Have not tried that prop on the plane in the air yet. For comparison a friend of mine had a TF-P51, stock G-62 set up the same, flying with a Mejelik 20/10 carbon fiber prop at the Denver Warbirds meet two years ago.
This prop let the engine wind up in the air into the high 8,000 or low 9,000 range and wow was it ever impressive. The plane would blow past ZDZ 80 powered p-51's like they were standing still. The only thing faster were a couple of jets. When RCIGN says a Zenoah likes to rev up believe him! Only disadvantage was a marginal take off and you had to "get the engine up on the pipe" that's an old formula one term guys, all us warbird fliers in Pueblo used to fly pylon! I would not recommend using the Mejelik only because the take off was so marginal but for performance it would be hard to beat.

Larry