31. The main rotors are both of fixed pitch design, with no articulation in any axis. 32. Most helicopters have a single main rotor but require a separate rotor to overcome torque. 33. This also resulted in the main rotor being mounted very close to the cabin roof. 34. They felt flying debris and later picked up pieces of the tail and main rotor . 35. This creates a force which cancels out the main rotor torque and provides directional control. 36. The main rotor had three blades with steel tubing for the centre, covered with wood. 37. The effect was to swap those letters before and after the main rotor scrambling unit. 38. The four-bladed main rotor consisted of two pairs of blades mounted one above the other. 39. Also, the coaxial main rotor configuration does not require tail rotor, which can improve survivability. 40. The main rotor system is of low-inertia and requires pilot skill to manage energy on landing.
