The rotor

“With enough power anything can be made to fly.”  This quote is even true for an inverted Eco 8.  I’ve seen the Eco 8 fly inverted on 10 cells with the stock rotor blades.  I’ve also seen it do this on 8 cells with symmetric blades.  Rotor blades are the “soul” of the helicopter.  The stock blades are of low quality but will get the job done.  Just don’t expect too much of them in a dive or inverted, they tend to flutter.  At moderate speed they cause a “pitch-up” of the helicopter.  Autorotation with them is asking for trouble.

For 3D flight, symmetric blades are the way to go because they perform the same at positive and negative angles.  I have never tried the blades made by Ikarus, but have not heard too much about them.  The carbon MS-Composite blades are a very good choice, but they are light.  Therefore, you will get high cyclic rates with them.  On the down side, they are difficult to auto with, and are still susceptible to cause some “pitch-up” at high speed, but that can be overcome with your thumb. 

The best blades, in my opinion, are the BBT (Big Boy’s Toys) blades.  These carbon blades are heavier (80 grams each) than the MS, but are harder to find in the US (midlands UK).  They will auto great, and will not cause pitch up except in a dive, and even then it’s slight.  To further reduce pitch up you can increase RPM and/or reduce slop in the control system.  With the BBT blades the Eco 8 flies very smoothly, but you must use large servo arms with the Bell-Hiller Mod to get good performance, as the extra weight will reduce your roll rate.