flyrotary@lancaironline.net Mailing List Archive

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Interestingly, I talked to Clark yesterday and decided not to trim my prop 76x88 at all. I am getting close to 6000 rpm on take off at finally got 6800 rpm at WOT at 3800 MSL. However, my ROC only approaches 2000 fpm (more like 1800). In discussion with Clark, we decided that given my heavier aircraft and primary interest in take off and initial climb that any increase in rpm (by trimming the prop) would likely be off set by less initial thrust (from less prop disc area). So I was about ready to send my prop back just to have the protective wrappings put on it.

Perhaps I'll wait and see what these changes does to your performance, Rusty. Get that engine back together and let me know.

Ed A (Larger Monster Prop {:>))

----- Original Message -----

From: Tracy Crook

To: Rotary motors in aircraft

Sent: Friday, January 21, 2005 2:44 PM

Subject: [FlyRotary] Re: monster prop shrinking a bit

Uh oh, good thing Ed helped me get that 20B powered RV-8 project moving.

Tracy (shooting for 4000 fpm)

----- Original Message -----

From: Russell Duffy

To: Rotary motors in aircraft

Sent: Friday, January 21, 2005 1:49 PM

Subject: [FlyRotary] monster prop shrinking a bit

Greetings,

I talked to Clark at Performance Props today. I’m going to go ahead and send my prop in for final finishing, since the engine is down anyway. I reported that I’m currently getting 6000 rpm at 100 mph in climb, and 6800 rpm at WOT 8000 ft. I requested 6500 rpm in climb, which will make top RPM about 7300 WOT at 8000. He’s got to run the number, but the rough estimate is that the prop will change from it’s current 74”x88” form, to about 72”x82”. He seemed very excited about what this will do for my performance, in both climb and cruise.

I told him I need a guarantee that it will beat Tracy :-) Seriously, I told him that I was getting 2400-2500 fpm climb now, and wanted 3000 fpm. He seemed pretty sure this change can get me there :-)

Cheers,

Rusty (Tracy's going down)