spinkaan
Junior Member
HI eddie, please give us an update on the flight tests?
Peter
Peter
spinkaan;n1131910 said:Hello Eddie, It has been a while since I could fly with the GT carbon blades as we have had so much rain the last month that my runway was inundated with mud patches, I had a 2 hour flight today and oh boy did I get a surprise with the performance and smoothness and no cabin shake or stick shake. I found that on prerotating they spin up much faster to 180 rrpm than the original blades. On landing these blades just want to continue flying.. I set mine up with the shims for high altitude and one up with 40lt fuel the rrpm settles at 340 wit engine rpm at 4250 and cruising at 70mph.altitude 7000ft amsl with a high humidityof 85 %.
Mine is the first RAF in South Africa fitted with GT carbon blades and I am sure not the last. Thanks for your input.
C. Beaty;n1131928 said:I took a look at the Gyro Tech web site; their “gyro” blades are the NACA 8H12 airfoil, the “H” standing for helicopter.
They also list “helicopter” blades of NACA 23012 airfoil section and 7” chord which could be a replacement for Dragon Wings except for price.
They got their airfoils backwards; the NACA 8H12 was intended for helicopter applications while the NACA 23012 was used on the later models of Kellett and Pitcairn Autogiros. But many people also mistake the 8H12 as being a gyro blade because Bensen used it without telling anyone it was designed to be a helicopter blade.
When the first low turbulence wind tunnels came out in the late 1930s, NACA stumbled across laminar flow and to improve the performance of early helicopters, designed a family of 4 helicopter airfoils, the 7H12, 8H12, 9H12 and 10H12. But none of them worked any better than the NACA 0012 when built to full size and run on a whirl tower.
But that’s beside the point; since Eddie and others seem to be pleased with Gyro Tech rotor blades, Gyro Tech evidently have stayed faithful to the proper shape and correct chordwise balance.
My experience is very different, jC. Many years ago, when flying with Bensen type metal blades with adjustable incidence setting, I decided to see what would happen if the incidence angle was set as high as the adjustment would allow.Jean Claude;n1131943 said:I not agree, Chuck .
Chuck, I have almost no experience. But that would be like saying that the undersling setting was not relevant.C. Beaty;n1131949 said:I don’t recall the rotor vibration as being unusual as a result of coning angle. .