THE PRONE ORNITHOPTER

One of Leonardo’s best known flying machines is the pedal-powered ornithopter. The drawings show it without cloth on the wings, so you can see how the pedals and ropes move the joints and flap the wings. The pilot was to lie prone on a board and push on the pedals like climbing stairs, and the cruciform tail was attached by a pole to his head. How he was supposed to take off and land isn’t clear. Leonardo surely knew it wasn’t practical, but he made many detailed drawings of the mechanism anyway, as though he was more interested in showing off his engineering than actually getting it into the air. This paper version doesn’t flap, but it does keep the pilot aloft.

1 Fold Tail Part (2) ninety degrees. Glue the white part of Rudder (1) to it as shown.

2 Fold Tail Part (3) ninety degrees and glue it to Parts (1) and (2). Make sure the Tail Parts are parallel.

3 Fold Fuselage (4) as shown, overlap the top flaps, and glue them into place. Don’t glue the back of the Fuselage yet!

4 Fold Reinforcement (5) and glue it inside the Fuselage, with the creases just matching the front edge.

5 Glue the Tail Assembly inside the back of the Fuselage. The Tail should be parallel with the top of the Fuselage.

6 Glue Parts (6) and (7) together, flush at the front edge, to make the Fuselage Bottom.

7 Glue the Fuse-lage Bottom to the glue tabs on the Fuselage.

8 Use a round toothpick to roll Ballast Part (8). Fasten the end with a tiny bit of glue. Then, attach Ballast Part (9) and roll and glue it the same way, followed by Ballast Part (10). Make sure Leonardo’s face shows on the outside! Remove the toothpick.

9 Glue the Ballast to the front of the Fuselage, using the tabs and the underside of the top flap. Make sure Leonardo’s face is facing to the front!

10 Bend the Body Straps (11) and (12) and glue them into place. Strap (11) is also glued to the top of the Fuselage at the white mark.

11 Crease Wing Parts (13) – (17) about 10 degrees each, and glue them together as shown. Lever Part (17) is attached to the bottom of Part (13) at the center only.

12 Glue the Wing to the Fuselage at the white mark on the top of Strap (11).

13 Glue Supports (18) and (19) between the Wing Lever Part (16) and the Fuselage bottom at the marks. All done!