[Scott Burling]

We own a Navion and an RV-7A my wife got her ticket in October and had been looking for a "hot rod" to do light acro and something fast and efficient. We love our Navion because it's comfortable, I'm a big ole boy. So we have the station wagon and the sports coupe in the hanger. Two airplanes and a wife who loves to fly, she's smokin hot as well.....I'm a very lucky man!

We purchased a nicely equipped RV7A, IO-360L2A 180hp at 2700, fixed metal Sensenich, MGL Odyssey EIFS, AP, 2 coms, back up steam, empty weight with paint and fairings 1133. Only had the airplane 2 weeks and still transitioning its a little more responsive than the Navion.... my teeth stay dry I smile so much when flying the RV.

I'm used to a constant speed prop but can't do that with this engine and wanted an easy airplane for my wife. Static RPM 2050 to 2100 and flat out 2650. My thought is to put a 3 blade Catto prop and pitch for 3050. Because it looks cool, ground clearance, looks really cool, quieter, and the extra RMP=more HP= go faster, and it looks really cool. I'll have to hang quite a bit of weight on the crush plate to keep the CG forward so no weight savings. They run these engines at 3050 in Helicopters so why don?t we in airplanes? What's wrong or right with my thinking?

 

[sandifer]

My thought is to put a 3 blade Catto prop and pitch for 3050. Because it looks cool, ground clearance, looks really cool, quieter, and the extra RMP=more HP= go faster, and it looks really cool.

A 3-blade Catto will not be quiet at 3,000+ RPM, but it does make a sweet characterstic sound. You haven't made it clear specifically why you want a 3,050 target RPM, wide open down low. You are wanting to cruise at 3,050 RPM at full throttle at low altitudes? That'll burn some serious gas. You can cruise at full power at high altitudes, but the engine will not be developing full power, you can lean aggressively, and you won't see the same max RPM that you'll see down low.

I would suggest talking to Craig Catto about exactly what you're looking to get out of the prop. He's got lots of experience matching props with RVs. I have a 3-blade Catto on my Pitts that tops out around 3,025 RPM wide open straight and level down low. But this airplane is for aerobatics and the Pitts is so draggy that it needs the low-speed thrust of a prop pitched this way. I'm not looking for top speed or cruise efficiency. I can't advise you on running your standard Lyc at 3,000+ RPM continually. I can only tell you that lots of acro guys have been letting their their Lycs turn up in the 3,200-3,300 range for short durations on a downline. Been doing this for decades with seemingly no ill effects to the engine.

 

[Scott Burling]

I have a call into Craig. My thought was to get more static to get off the ground quicker. But don?t want to give up good cruise numbers..... I want the best of both worlds....I want a constant speed prop without controls?lol. Anyone have experience with eclectic control?