Class rules

International classes

For the international FAI classes F1D, F1M, F1L, F4F, we will use the rules found here:

Additional classes in the open competition


The basic dimensions and weights are as the ordinary F1M:

A.1 Wing (and tailplane) maximum span 460 mm
A.2 Model minimum weight 3.0g
A.3 Rubber motor maximum weight 1.5 g

F1M-limited has additional rules:

B.1 Maximum width of lifting surfaces 150mm
B.2. Maximum length of the model 650 mm (excluding propeller)
B.3 Maximum length of motor stick 270 mm (measured from the front of prop hanger to the front of rear motor hook)
B.4 Maximum prop diameter 350 mm
B.5 Mechanisms that alter prop diameter or pitch (i.e. VD / VP) are forbidden

Additional rule for competing:

C.1 Competitors flying in F1M-limited class are included in the results of F1M. However a competitor may announce that (s)he is flying F1M-limited. The two classes are exclusive – if (s)he makes one flight with a model not eligible to F1M-limited class, then all the results are counted as F1M.

Peruslennokki (“The basic model”) rules:

1) Maximum permitted projected wing span 480 mm.
2) Maximum wing width 80 mm.
3) Monoplanes only.
4) Maximum tailplane area 45% of wing area.
5) Maximum prop diameter 250 mm.
6) Model uses rubber motor for motive power. Motor weight is unlimited
6) Model minimum weight (excluding the rubber motor) 6 g.
7) Mechanisms that alter prop diameter or pitch (i.e. VD / VP) are forbidden

A link to Tapios design & kit for peruslennokki (in Finnish) is:

Mini Stick

  1. The Mini-Stick model shall be a monoplane covered with any commercially available material sold in sheet form. Microfilm is not allowed.
  2. The maximum projected wingspan shall be seven (7) inches.
  3. The maximum wing chord shall be two and one-half (21/2) inches.
  4. The maximum length (from front of nose bearing to front of rear motor hook) shall be five (5) inches.
  5. The maximum length from front of nose bearing to rear most part of model shall be ten (10) inches.
  6. The projected area of the stabilizer shall not exceed 50% of the projected area of the wing.
  7. The maximum diameter of the propeller shall be seven (7) inches. The propeller shall be constructed of wood. Wire shafts are permitted. Hubs that allow blade replacement and/or manual pitch adjustment are allowed. Mechanisms that cause variable pitch and/or variable diameter of propellers while in flight shall not be allowed. (Natural flexing and flaring of wooden blades is allowed.)
  8. The minimum overall weight of the model (without motor) shall be 0.015 ounce.
  9. Construction is to be primarily wood, with adhesives used only for joining. Tissue and/or thread is permitted for wrapping bearings, hooks, and for making sockets, if desired. Boron, carbon fiber, Kevlar, and fine wire bracing are not permitted.
  10. Mechanisms that restrict the torque available to the propeller are not allowed.


  1. The model shall be rubber powered and covered with paper or commercially available plastic; no microfilm allowed.
  2. The total maximum projected wing area shall be 30 square inches. There is no restriction on the stabilizer area.
  3. All wing, stabilizer and rudder wood including wing posts shall be 1/16” square wood minimum, except ribs shall be 1/32” X 1/16” minimum. Posts may be rounded in the area of the mounting tubes.
  4. The motor stick shall be from solid wood of 6” maximum length measured from the front thrust bearing face to the front of the rear hook.
  5. The propeller shall be 6” maximum diameter with flat blades from balsa no thinner than 1/32”.
  6. The minimum weight of the model shall be 1.2 grams without rubber motor.
  7. No special materials such as boron, carbon fiber or foam are to be used.