Prop Questions

[snowyriver]

For those of you running 180 hp engines, what prop are you using and can you give me an idea of static, take-off, and cruise rpm? I guess WOT rpm would be good as well. I'm specifically interested in Catto props but would welcome all.

I'm using a 82-46 catto on a murphy rebel now and here are my numbers

aerosport 0360 with 300 ish hrs
static - 2240

take-off - 2330

WOT - 2600 100 kts


I was using a sensenich 76-54


Don't recall static rpm

WOT- 2700 122 kts

This prop is obviously wrong and Craig has said as much; they are making me an 80-52 now. I don't understand how that'll let me spin up faster. I'm just looking to save some weight, improve low end, and I don't mind losing some top end but not all of it!

Thanks Craig

 

[skywagon8a]

I'm using the Whirlwind ground adjustable 200G. It is not a weight saver but it does give me any choice of blade angle that I wish with the turn of an allen wrench. Saves buying and trying several different props. The performance is excellent.
http://www.whirlwindaviation.com/props/STOLGseries.asp

 

[PerryB]

I don't see how losing 2" on the diameter but gaining 6" on the pitch is going to do anything but make it faster on top, and probably make the bottom end worse, unless it's an entirely different airfoil/profile. I would think staying with the 82 dia. and losing 2-3" pitch would be the answer. I like dealing with the Catto's but they seem to forget we are dealing with aircraft that top out a little over 100. These are not Cassut racers. I had them make me an 82" prop for an O320/150 about 2 years ago and gave very detailed specs. pertaining to the Borer I was running. Static, 60mph climb, WOT run-out etc. and told them I wanted a prop to enhance takeoff and climb.I got a prop that was overpitched by about 2 inches and wouldn't turn up. Rather disappointed. Its a shame because it was a beautifully made prop and ran remarkably smooth. For some reason they are predisposed to making their props too fat. At 80" diameter I would think about 49-50" pitch would be about right.

 

[WanaBNACub]

Hmm, I am with Perry. I don't know that you are going to gain what your hoping. I have an 0-360 PA-18 with an 84/43. I am getting about 2550 on takeoff at 80mph climb, WOT straight and level is 2680. It cruises at 105mph at 2400.