Prop recommendations for O-360

[CaptPausert]

I am working on my 9A and an A&P friend of mine has an O-360 he is willing to sell me for a really good price. I was originally looking at the 3 blade composite CS props but my budget is getting a bit tight with all of the price increases. Could anyone share if the difference between the 2 blade aluminum CS prop and the 3 blade composite is worth the 7-8k price difference? Also is the CS prop worth it? I have heard it helps slowing the plane down when coming in for landings but I have not had a chance to compare. Thanks

 

[John Tierney]

You are very early in your build, so I wouldn't be in a rush to buy a prop.
If the engine is a good deal, make sure you get it "pickled" for long term storage. A constant speed prop will require a hollow crankshaft, so make sure the engine is at least set up for that.

I have a 7A, and getting the lower cowl on-off is no fun with a 2 bladed prop, because the cowl has to travel down the nose gear, sliding forward all the time it goes down. I know it has been done, but I would think a 3 blade prop on an "A" model is a real challenge.

 

[alpinelakespilot2000]

? Also is the CS prop worth it? I have heard it helps slowing the plane down when coming in for landings but I have not had a chance to compare.

If money no object? Absolutely a constant speed is worth it. That said, I've been flying a fixed pitch 2-blade Catto for 12 years and have absolutely no regrets. Would probably do the same thing today, even if I had the money for constant speed, but that's mostly because I really value simplicity and (basically) zero maintenance. Others value other things.

Slowing down a fixed pitch 9/9A in the pattern is not an issue, assuming even a modest amount of planning, so I wouldn't factor that too much into your decision.

Good luck with this "never-ending-debate" question.

 

[guccidude1]

I have a RV-9A with and IO-360A1A engine. I have the the Sensenich 72x83 prop. Good climb out at 100 kts and cruise a 150 kts at 2550 rpm 8.2gph. avg cross country. When I send it in for overhaul I will have it repitched to 72x85. Dan from Reno.

 

[JMiller]

Catto & Sensenich

I fly an RV9A with an O-360 A2A that I did not build. It came with a Catto 72" diameter, 74.5" pitch prop on it. The airplane had been built with the Sensenich 72" diameter, 84" pitch prop and it was included in the sale. A short time ago my brothers and I flew a sort of test flight with the Catto and then installed the Sensenich and compared it. This was the information we came up with:
Catto
Static RPM 2,170
Time to 10,000' 7 Minutes, 40 Seconds
Cruise RPM WOT 2,600
Cruise Speed WOT 159KTS

Sensenich
Static RPM 2,110
Time to 10,000' 8 Minutes, 15 Seconds
Cruise RPM WOT 2,660
Cruise Speed WOT 158KTS

Field elevation was 750' and we climbed at 100kt. I don't understand how the Catto can have a higher static RPM and still lower RPM WOT at 10,000, but that's what we saw that day. The flights were about two hours apart. For a fixed pitch propeller, I like the Catto, but a constant speed would be even nicer.

 

[Godo]

Too low RPM on static WOT?

Sensenich 72" diameter, 84" pitch
Static RPM 2,110
Time to 10,000' 8 Minutes, 15 Seconds
Cruise RPM WOT 2,660
Cruise Speed WOT 158KTS


Hi,

I'm rebuilding an old RV6 with a O-360 and a Sensenich 72FM, with a 87 pitch.

After a couple of years in the hangar, I run the engine for the first time this morning. I was expecting 2200/2300 RPM static WOT, but after some testing, we can't get beyond 2000 RPM.

With your data above, I feel a bit more comfortable, but still I feel is a bit low even with the 87 pitch.

Does anyone have an advise pls?

Thanks in advance

Godo
RV6 in Barcelona