HL-2A - Weight shift helicopter - Indirect transmission with U-joint
785 views · Published 1 July 2017 · 2:56 · Indexed 29 October 2026
Channel: RCmags · 2017 · Entertainment
Second attempt at a homemade helicopter. This is a refinement of the previous HL-1B. This model does not have a single stage gearbox driving the main rotor directly. Rather, it has a multistage gearbox that drives a shaft connected to a universal joint. The universal joint allows the rotor to be tilted side to side, hence providing longitudinal control. This change allowed the center of mass of the aircraft to be far lower than on the HL-1. No longer was the mass of the motor and the transmission placed above the aircraft. These heavy elements are now placed far closer to the center of mass. The benefit of this slight increase in complexity is a drastic decrease in the rotational inertia of the helicopter. This made the controls far crisper as the overall reaction time was decreased; the controls had a far more instant response as compared to the HL-1. This model was also equipped with a one way bearing to allow the main rotor to enter auto rotation.
