Powerflow experience, anyone?

[whee]

Inspect and repair as necessary. On a prop it would likely be strip the paint, smooth the nicks, inspect for cracks, repaint. and reseal the hub.

[Pbruce]

Ah. Thanks guys. I’ll probably go with the carbon WW blades to keep the weight down but if I’m unable, it’s good to know that service is available. I thought prop shops insisted on all or nothing. I’d be awfully surprised if these blades need work, so this is good to know.

[zkelley2]

Thanks for the Whirlwind pricing info, Z. The original 2-blade prop looks good to go as is, but it’s only 76” diameter and weighs about 59lbs with blades. Overhaul status is TBD. Putting modern carbon blades on while overhauling the prop will cost about $254 per pound of weight saved. Of course anything you touch on the power plant will be costly. No wonder fixed pitch props are popular!

A constant speed prop is probably the cheapest horsepower you can bolt on an engine though.

[svyolo]

And it isn't an engine tuning experiment.

[Pbruce]

Update on prop/exhaust/engine selection for Patrol: The Cardinal engine fell through. I’m getting a Bob Barrows O-360 rebuild next month with new cylinder assemblies and at least one electronic ignition plus a mag. I will almost certainly go with Vetterman exhaust. I really appreciate all the input from others on this site. I even bought a Jihostroj governor from a BH builder on this site!

WRT to re-blading a McCauley prop with WW carbon blades, I worked hard to do this, but ultimately gave up. Whirlwind was absolutely impossible to deal with. Seemed nice enough on the phone the one time I could actually talk to someone. Other than than that, they wouldn’t pick up the phone and wouldn’t answer email questions such as: which hubs will fit your blades? Additionally, their website says they no longer produce any composite bushplane props, although they say they still support them. Again, they wouldn’t answer any questions about availability, or anything else for that matter. I even wrote them a letter saying that I really liked and wanted to buy these blades from them. I said I thought there was a growing market for for them, in my opinion. I said I wanted to buy if only they would have helped me do so, but that I was going to go with Hartzell due to our inability to communicate. They did not respond.

I went with a Hartzell Trailblazer with 14” spinner, which I purchased through Avipro. It’s a lightweight thing of beauty. I could have bought one from a local Glastar builder, but his price through Glasair was a grand more than Mark G charged me. Mine is two years newer, came with the spinner I wanted and comes with a letter from Hartzell stating that it’s for my O-360 A1A for the BH Patrol, without rpm limitation except 2700 max rpm. Very importantly, my transactions on this high-cost item were with a completely trusted source (Mark Goldberg). This prop is a significant expenditure, but it seems like the best way to get good performance with a fairly basic engine setup. Plus I like the other benefits (light weight, damage resistant and fixable, quieter than FP in cruise, more drag on landing).

[rodsmith]

Sounds like a great set up. I'm guessing WW is too busy building props for RVs to mess with blade work.

[Battson]

As with so many things in aviation, it always pays to stick in the middle of the road. While it is tempting to experiment, there are always risks.

[Pbruce]

Could be. The guy sounded really busy. As with so many of these technical specialty businesses, they may have only one or two people who can really answer all questions. Then they get tasked with customer quotes, supervising workers, and doing production work themselves. It’s too bad for the Bearhawk community though; it would have been great to have another option, especially a cheaper one. I’ve seen these props and talked to two BH patrol owners flying them and the word is very good.