Prototypes

Standard Design This was a basic starting point in our design that offers an improvement over the wood and carbon fiber symmetrical blades as well as a good average lift/drag ratio. All surfaces are smoothed over to reduce drag and the end tips are rounded and optimized to reduce vortexes.

Extra Lift This design features a theoretical 10% increase in lift with only a .4% increase in drag (at 3 degrees pitch); however, because the Reynolds number is low, it is expected that the theoretical increase in lift will be less while the increase in drag will be greater than predicted. All surfaces are smoothed over to reduce drag and the end tips are rounded and optimized to reduce vortexes.

Less Drag This design features a .2% decrease in drag with a 4% decrease in lift (at 3 degrees pitch); however, because the Reynolds number is low, it is expected that the theoretical decrease in drag will be greater while the decrease in lift will be less than predicted. All surfaces are smoothed over to reduce drag and the end tips are rounded and optimized to reduce vortexes.

Tapered Design - Airfoil Optimization This design features a varying airfoil profile from the blade grips to the tip that takes advantage of airfoil shape versus air speed. The air speed at the tip of the blade is much higher than at the blade grips; by changing the profile the lift can be more uniform over the length of the blade while optimizing the overal lift/drag ratio. Many full scale helicopters use this principle; however, because the Reynolds number is much lower for the Blade CP, it may not be as effective. All surfaces are smoothed over to reduce drag and the end tips are rounded and optimized to reduce vortexes.

Tapered Design – Reynold Number Optimization This design features a varying airfoil profile from the blade grips to the tip that takes advantage of airfoil shape versus Reynolds number. The Reynolds number at the tip of the blade is much higher than at the blade grips; by changing the profile the lift can be more uniform over the length of the blade. The Reynolds number is much lower for the Blade CP when compared to its full scale brothers, this design takes advantage of known effective airfoils at low Reynolds numbers. All surfaces are smoothed over to reduce drag and the end tips are rounded and optimized to reduce vortexes.

Extra Stability 1 When viewing full scale helicopters in flight you can see that the blades form a V as seen below. The stiffness and lacking of flapping mechanism does not allow the same phenomenon on model helicopters, this design attempts to create that effect and result in more stabile flight. It is expected that the helicopter will be more stable upright with these designs and be more responsive when inverted, a characteristic which may or may not be desired. These blades feature a similar lift/drag ratio as the standard design. All surfaces are smoothed over to reduce drag and the end tips are rounded and optimized to reduce vortexes.

Extra Stability 2 This design is very similar to Extra Stability 1 except that the lift/drag ratio is shifted to reduce drag. All surfaces are smoothed over to reduce drag and the end tips are rounded and optimized to reduce vortexes.

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