Propeller recommendations for lycoming 0-360

[Gary Wallace]

I got my o-360 a1f6 for my bearhawk! It was, as previously mentioned, on an aeronca sedan, and it came with a mccauley 82 42 propeller. I am looking for opinions on this propeller, engine combination for the bearhawk. Any input would be appreciated. Thanks , gary

[whee]

I know nothing about the a1f6 but it is my firm option that the wide performance capabilities of the BH warrants a constant speed prop. If Bob, whom is a firm believer in lightness and simplicity, thinks a CS prop is the way to go then I'd really think hard about using a fixed pitch. I know Bob can drill a solid O360 crank to make it compatible with a CS prop but I don't know about the case...that's if your engine isn't CS capable already.

[H. Ivan Haecker]

I am building a Patrol and also plan on using a CS prop. The CS can be more fuel efficient since you can adjust rpm and manifold pressure independent of each other. But,I don't think a fixed pitch is out of the question.I fly an rv-4 with a fixed pitch and it has an even wider range of performance, at least if you are looking at the spread between top speed and stall speed. I think a fixed pitch prop can be configured to go just as fast as a CS or it can be configured to climb just as fast. It just can't do both. Most people who use fixed pitch props compromise somewhere in between. However, there is a huge cost difference (and weight difference) between them. If you want the max performance, go with the CS. Unfortunately, I can't tell you if the prop you have is suitable. But I'll bet there is a good compromise fixed pitch prop somewhere that is. Guess you'll have to ask Bob. Just my two cents worth.

Ivan Haecker p150 QB that is going slowly together

[Bcone1381]

Being able to economically and quietly cruise along with my constant speed prop set at 2000 rpm sure sounds nice. But when that decision time arrives for me, I will be contacting fixed a pitch prop manufacturer called Catto Propellers. They tell the Acro community that their prop "relieves crankshaft stress by taking 40 pounds off the nose." Ground Adjustable props add more variables to the decision.

http://www.cattoprops.com

[Gary Wallace]

i am open to options depending on the pocketbook at the time.. this prop was on this engine on the aeronca sedan and was a seaplane. i believe it is considered a borer prop...which is would think would be a climb prop.. dunnow for sure. my other option i was considering would be to repitch to a 44 or 45 from 42 as i would think this would give me a better cruise performance, but would still be a good pitch for a decent rpm at take off off of the ground,,,not water. I am of course considering this as i have a very good option for a propeller, i think, and a constant speed is a tad pricier of course. Still looking for opinions from those of you who might know better than myself. thanks to those of you who have replied so far. and, my engine does have the hollow crankshaft to allow for a constant speed prop as well. thanks again. gary

[marcusofcotton]

Gary, with that prop you'll join me at the slower end of the Bearhawk spectrum, but climb will be great! Even with kicking up the pitch a bit. You already have the prop, it's already a used prop so it won't lose any value by trying it first. It will be nice to have the comparison rather than regretting not trying it.

[Phil]

You might look into the Catto props too. They supposedly give a wider speed range than a metal fixed pitch and are a heck of a lot cheaper and lighter than a constant speed.

And a 82 x 42 prop would be considered a slow, climb prop in a 150 hp Cub. Most of them are running at least 44" pitch for climb props. You're going to red line at 100mph with that prop.

Edit: If you decide you don't want it, you shouldn't have any trouble finding a buyer among the Super Cub STOL crowd.

[Battson]

In my experience, a little more weight on the nose can be helpful in the 4 place.

If you can afford it, I would go for a basic constant speed prop, if you want maximum performance.
Governor (e.g. PCU-500X) can be had reasonably cheaply, they are small and light. Combined with a used C/S prop and you aren't going to be too poor...

Of course you can easily save money and sacrifice a little performance, and stick with a fixed pitch prop.

It's worth remembering that weight isn't the ultimate driver for performance, just one of several main variables.

[N942VT]

Gary, I would consider a constant speed, I believe you would enjoy the benefits of best of both worlds. My Bearhawk has a Hartzell 84 inch on an O360, PCU governor and I couldn't be happier. It's the initial cost hit that hurts at first but I wouldn't do it any other way with this airplane. Great short take off performance and then you get to use the legs of the Bearhawk when you want it. Just my opinion and I'm sure a fixed pitch could be set up so you'd be happy but this is an area I feel I got it right the first time.

[whee]

I don't have a specific recommendation for you but I wanted to add that you should choose your prop/engine combination carefully. Make sure you recognize the risk of using a combination that has not been tested harmonically. I'm a chicken so will be using prop/engine combination that has been tested. Last thing I want to do is shuck a blade.

[bearhawk2015]

I would just use the prop you have and get it re pitched , it's paid for and it works, unless you have some money burning a hole in your pocket just use what you have, most flights will probably be local anyways so you don't need to go fast

[Gary Wallace]

N942VT..... have you got the model of your blades on your pcu5000 governor ? I would like to do some pricing on blades for the governor maybe look for some used blades I know nothing about constant spped props yet

[Peter Bishton]

Gary, Eric Newton has details of performance for an O360 see http://mybearhawk.com/flying/25hours.html for a fixed pitch prop.
My father has designed and built on 500 props ( wooden) from about 1967 till approx 10 yrs ago in Australia. Varieties from Corby starlets to tailwinds, austers, Tigers, T18s, Kr2s and glasairs. His advice to me is to go with several more inches if pitch than Eric tried out. That being about 58" to 60". Funnily enough that is what Eric says in his article. Dad also did quite a bit of work in a glider tug with an O360 working out of western NSW and its combo was similar to that. It was an bellanca scout. It had a busted Hoffman prop which the client eventually sent over to try and get copied . I am going with a fixed pitch for the O360. Peter B plans # 1134 - 4 place.

[Gary Wallace]

So peter>>> that would be a 76" diameter prop....would you or anyone know if my 82 42 finer pitch prop could be repitched to compare to a 75 58 for instance...or clip the 82 a few incches and repitch? just wondering is all....or would i better to just sell my prop and stop the guessing game...

[Peter Bishton]

Gary I just flew back into Aus from NZ from 2 weeks vacation. My dad has sent a response which I will try and post tomorrow. I know you may have moved on which is probably good as he calculates at 2700rpm that prop will only be capable of 100 knots ( I am doing it from memory from an email he sent me.) I assume the prop was wooden / timber hence his advice would be relevant as that is what he worked with. Peter

[marcusofcotton]

If you don't want slow, you won't be able to repitch the Borer enough to get out of slow. Sell it, if it's in decent shape, it will sell with the STOL crowd.