The models are divided into classes:—
§ 2. Aero Models Association's Classification, etc.
| A. | Models of | 1 sq. ft. | surface | and | under. |
| B. | " | 2 sq. ft. | " | " | |
| C. | " | 4 sq. ft. | " | " | |
| D. | " | 8 sq. ft. | " | " | |
| E. | " | over 8 sq. ft. |
All surfaces, whether vertical, horizontal, or otherwise, to be calculated together for the above classification.
All round efficiency—marks or points as percentages:—
| Distance | 40 | per cent. |
| Stability | 35 | " |
| Directional control | 15 | " |
| Gliding angle | 10 | "[49] |
Two prizes:—
One for length of flight.
One for all-round efficiency (marked as above).
Every competitor to be allowed three trials in each competition, the best only to count.