F3B

F3B is a class of the Fédération Aéronautique Internationale (FAI) for electric-powered radio-controlled sailplanes used in multi-task endurance competitions. It is part of the F3 family of glider classes and is designed to test energy management, aerodynamics, and piloting skill in electric sailplane racing.

Aircraft in F3B are typically high-performance, lightweight sailplanes with long wings for efficient soaring. They operate under rules that govern dimensions, weight, and propulsion, and are designed to maximize endurance and glide performance. Electric power is used to assist climb and setup phases, but the emphasis of the class is on efficient, skillful flight to complete the required tasks.

Competition format in F3B consists of a series of rounds, each including multiple flights within a designated time window. Pilots aim to complete a set of tasks that commonly include duration (time aloft), distance to a goal, and sometimes height or other objective criteria. The tasks are designed to evaluate the model’s ability to stay aloft, cover distance, and maintain performance under various conditions.

Scoring in F3B is task-based, with points awarded according to how well the flight meets each objective (time aloft, distance achieved, and other task-specific criteria). Penalties may apply for rule violations or deviations from the required flight profile. The class is governed by FAI regulations and is widely practiced at national and international levels, with regional and world championships held under the F3B ruleset.