Built-up Balsa Aircraft Modelling

Control-line; Radio Control; Free Flight


Group One 8 – 11 years
Group Two 12 – 14 years
Group Three 15 – 17 years
Group Four 18 years and over

Additional Conditions of Entry for Built-up Balsa Models

Pre-cut models shall not be accepted for the Group 3 and Group 4 level, but may be submitted at the Group 1 and Group 2 level.

The maximum wing span of any model shall not exceed 1m.

Level of Difficulty

Pre-cut or partially built-up models require less effort than a model that is fully built-up, and will be marked accordingly.


All base components, i.e. wing, tailplane, etc shall be attached and correctly aligned for flight. All auxiliary components, i.e. engine, control surface linkages and hinges etc shall be installed correctly.


On those parts of the model that have been painted, care shall be taken to avoid brush marks, paint runs etc.

A judging formula has been developed and shall be applied as follows:

A model which is fully painted shall be marked out of 20 points

A model which is partially painted and covered with plastic film shall be marked out of 15 points

A model which is fully covered in plastic film only shall be marked out of 10 points


The different parts of the model shall be glued to ensure all joints fit tightly together. Gaps between joints are to be avoided. Similarly, excessive use of glue and smearing of glue is also to be avoided.


Attention shall be given to the covering materials used on the model and how they have been applied. The following shall be taken into account; creases in the covering, sealing of edges, excessive amount of dope used resulting in warping the structure, too much heat being used to apply plastic coverings, if used the proper application of decals or decorations.