Need Bensen/Brock Blades ! ! !

[Jazzenjohn]

Why is it that Dragon Wings are the only blades that can't be hand started, or at least are so difficult to hand start?

 

[Ron Iaconis]

Blades that have a twisted spar

Blades that have a twisted spar

Any blade that has a twisted spar( Hughes 269,ex.) are not easily hand started. I am not sure how much DW are twisted, but at the tip, they are somewhat positive in angle of attack. Whereas most others( Asymetrical blades) they are a " straight" blade, having no twist, and are only 1 to 1& 1/2 degree positive collective. This allows them to come up to flying speed when only hand started to say about 60 RPM. The twisted ones( usually go to say about possibly 5 degrees positive) need to get spinning over 100 RPM to keep from flapping on the retreating blade.