HeliQuads (Variable Pitch Multicopters)¶
Copter-3.6 (and higher) supports HeliQuads, also called Collective Pitch Quadcopters or Variable Pitch Multicopters.
These vehicles use independently controlled collective pitch on each of 4 rotors, with a single electric motor that powers all 4 rotors at the same speed via belts and a torque tube. It is highly aerobatic, capable of inverted flight but can suffer from high vibration levels.
Connecting and Configuring¶

- each servo should be connected using the same outputs that would be used for motors on a regular multicopter (see order here)
- the motor’s ESC should be connected to the flight controller’s channel 8 output
- traditional helicopter firmware should be loaded onto the vehicle.
If using the WLToys Assassin V383 a parameter file is available here and can be used to set all parameters immediately. For other builds these are the standard params that should be set:
- FRAME_CLASS to 13 (HeliQuad)
- FRAME_TYPE to 1 (“X” if front right motors spins counter clockwise) or 3 (“H” if front right motor spins clockwise)
Similar to a traditional helicopter an auxiliary switch should be set to “Motor Interlock” to turn on/off the motor. Normally this is channel 8 so you could set CH8_OPT to 32.