The FAI (www.fai.org) who are the world organising body for all sports aviation including model flying have system of codes for sporting classes for competition aircraft.

In aero modelling competitions, these are given the designation 'F'. So there is F1 to 6. Each of these designations are split into groups A up to K (at the moment). Each class comforms to strict rules.


F1 = Free Flight Models
(With various sub sections)

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F2 = Control Line Circular Flight

• F2A = Speed Models
• F2B = Aerobatic Models
• F2C = Team Racing Models
• F2D = Combat Models

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F3 = R/C Flight

• F3A = Aerobatic, Powered Models
• F3B = Thermal Soaring Gliders
• F3C = Helicopters
• F3D = Pylon Racing, Powered Models
• F3F = Slope Soaring Gliders
• F3J = Thermal Duration Gliders
• F3K = Hand Launched Gliders

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F4 = Scale Models

• F4B = Free Flight Scale
• F4C = R/C Flying Scale

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F5 = Electric Powered Aircraft

• F5B = Motor Powered Gliders
• F5D = Electric Powered Pylon Racers
• F5F = 10 Cell Motor Gliders

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F6 = Airsport Promotional Class

F6A = Aeroplane Artistic Aerobatics

F6C = Helicopter Artistic Aerobatics


I think I've covered everything, but may have missed one or two. If I've got any wrong please correct me!