- Maximum projected wingspan shall not exceed 16 inches (40.64 centimetres).
- Maximum wing chord (measured parallel to the direction of flight) shall not exceed three (3) inches (7.62 centimetres).
- The diameter of the propeller(s) shall not exceed six (6) inches (15.24 centimetres).
- The length of the model excluding the propeller(s), but including the thrust bearing(s), shall not exceed 14 inches (35.56 centimetres). This measurement will be made in the direction of flight and will include surfaces, which extend beyond the thrust bearing or fuselage end because of a sweep or unusual mounting.
- The fuselage structure must include a box, which has minimum dimensions of 1.5 inches x 2.5 inches x 3.0 inches (3.81 centimetres x 6.35 centimetres x 7.62 centimetres). The width (the horizontal dimension perpendicular to the line of flight) of the fuselage shall not exceed three inches (7.62 centimetres). The box must be enclosed within the fuselage structure and must be covered so as to restrict free air movement through the box. Normal sag of the framework between supports caused by the tension of the covering will not be considered as a violation of this rule.
- The fuselage structure must be built-up so that the longitudinal members (the longerons) support the forces produced by the rubber motor. A solid or hollow motor stick with a lightweight structure added on is not acceptable.
- The fuselage must have a transparent windshield and side windows of at least one (1) square inch (6.45 centimetres area each). An open cockpit design need not have side windows. But the windshield must meet the one (1) square inch rule (6.45 square centimetres) and must stand at least 3/4 inch (1.905 centimetres) above the top of the fuselage.
- The model must have at least two (2) wheels of at least 3/4 inch (1.905 centimetres diameter, each on a separate leg, which rotate freely and support the model for takeoff and landing.
- All flying surfaces must be covered on both sides or must be solid material with a thickness of at least 1/16 inch (1.58 mm) at the maximum point in each chord wise element.
- The total projected area of the secondary horizontal surface(s), excluding that inside the fuselage, shall not exceed 24 square inches (154.8 square centimetres). This may be a conventional stabilizer and/or a canard surface.
- The airframe, excluding the rubber motor(s), shall weigh at least seven (7) grams.