How Does a Helicopter's Stabilizer Bar Work?

Significance

• Stabilizer bars stabilize the helicopter while in flight. There are two types: the Bell system and the Hiller system, each deriving their names from real-world helicopters. The Bell stabilizing method places a small bar on top of the main rotors and limits gyroscopic forces, while the Hiller system uses a stabilizer bar with paddles and affects stability aerodynamically.

Function

• On the Bell system, maneuverability is sacrificed for stability. Because the Bell system hinders gyroscopic forces, control inputs lag slightly while the the main rotor works to catch up with the stabilizer bar. With the Hiller system, control inputs are immediate as this stabilization system uses an aerodynamic method to stabilize the rotor system. This latter feature makes the Hiller-type helicopters more desirable for aerobatic activities.

Prevention/solution

• Most RC helicopters on the market today use a combination called the Bell-Hiller system. This setup combines the benefits of both systems and provides the most stability while preserving maneuverability.