Chris said, " . . . the Warnke "almost constant speed prop" was popular IIRC. It had the right flex tendencies to flatten out on takeoff then twist back to its natural steeper pitch when forward airspeed was gained."
The Warnke was and is a gorgeous prop and is a treasure if you can find one with the right diameter and pitch that you're looking for. His daughter took over the business and I've heard didn't do much with it. Lonnie Prince claims some of the same characteristics for his props and I don't doubt that it's true to some extent. His blades have some very complex and beautiful shapes. If he would just get rid of those drag-producing "P-tips" and put some urethane leading edges on his creations his props would be a lot better. Maybe he has done these things . . . I've not been keeping track. Meanwhile, Catto is the way to go for the ultimate in a wood/composite prop. He has incorporated the aerodynamic design work of Paul Lipps into his props and, in fact, is the one who builds those fabulous props (designed by Lipps, RIP) you see on the Reno Biplane racers such as Phantom. http://www.eaa.ca/experimenter/articles/2009-07_phantom.asp Meanwhile, I've got no complaints with my Sterbas. Mike KSEE ____________________________________________________________ How Old Men Tighten Skin 63 Year Old Man Shares DIY Skin Tightening Method You Can Do From Home http://thirdpartyoffers.juno.com/TGL3141/54d05a481b8f85a482855st03vuc