flybarless

Flybarless refers to a stabilization approach used in radio-controlled helicopters that removes the mechanical stabilization flybar from the rotor head and replaces it with an electronic stabilization system. The core component is a flybarless (FBL) unit, or flight controller, which uses sensors and software to maintain or assist the helicopter’s attitude and motion. The system still controls the swashplate and the tail rotor through the helicopter’s servos, but it does so under electronic guidance rather than mechanical aid.

Operation centers on sensors and control algorithms. An inertial measurement unit, typically including gyroscopes and accelerometers, provides real-time data about orientation and rotation rates. Some setups add magnetometers or other sensors for improved reference. The FBL unit runs stabilization algorithms (often PID control) to dampen disturbances and maintain the commanded attitude. Pilots can select from flight modes such as stability or sport, and adjust gains or other parameters through a configuration tool or radio interface. The result is improved stability, smoother cyclic response, and advanced features like auto-leveling or heading hold in some systems.

Advantages include smoother handling, more precise cyclic and tail responses, easier setup, and the ability to implement sophisticated flight modes without a heavy mechanical flybar. Modern FBL systems are used in a wide range of sizes and can enable lighter head designs and reduced maintenance in some configurations. Disadvantages include higher cost, added complexity, and a reliance on reliable electronics and power. Proper setup, calibration, and periodic checks are important to ensure safe and predictable operation.

Typically associated with hobbyist RC helicopters and some multirotor platforms, flybarless technology has become mainstream since the late 2000s, with multiple brands offering configurable FBL units.