With a brushless motor and a TRex tail rotor mechanism I could assemble a simple variable pitch system. I measured and it generates 700g with the TRex 500 tail rotor blades. I tried the Trex 250 blades from the main rotor but although they are longer the thrust is smaller, just 400g. This is probably because the motor doesn't have enough torque. This could be used for a variable pitch quadcopter or with an airplane. Specs: Motor: Hextronik DT750 ESC: Plush 25A Battery: Turnigy 2200mah 25C Tail rotor: HK-500GT Wood to support the tail mechanism: 38mm tall Source: http://diydrones.com/profiles/blogs/simple-variable-pitch-for-brushless-motor
