The Hoverfly and Hurricane paper helicopters I made previously each performed excellently and were very well received by the Instructables community. To give aviators who liked those birds more amusement, I decided to make another. The Tornado is a paper helicopter with five rotors, designed as the "middle size" chopper--smaller than the Hurricane, larger than the Hoverfly.

Like the Hurricane, the Tornado is among a small group of paper aircraft that qualify as "paper helicopters" not of the traditional two blade design. Because of the Hurricane's great performance and original design, it was the conceptual basis for this project's layout.

Like the previous helicopters, the Tornado is designed for many uses, including as a research testbed for use in classrooms. Some potential experiments this aircraft could be used in include:

Air resistance
Wing area versus weight hangtime comparisons
Wing area adjustment hangtime comparisons

TAA USAF Designation: HD227-1

Step 1: Materials

Required:
1 Piece of 8 by 10.5 inch graph paper
Tape
Scissors
Pencil
Ruler

Step 2: Begin Construction

Begin making your Tornado by marking out a box of 10 by 10 boxes, with a 1 by 2 additional outcropping on a single sheet of graph paper. At the top, mark a solid line 6 boxes in length, every 2 boxes from the corners of the main box. From this line, mark a dotted line that stretches from the side of the boxes to the other, including the outcropping. Below the vertical lines intersection with the horizontal line, extend them as dotted lines.

Your Tornado should now look as pictured. Cut the airframe out along the solid outer line.

Solid lines indicate places to cut. Dotted lines indicate fold lines.

Note: 1 box = 0.25 inches

Step 3: Making the Rotors and Fuselage Folding

Cut along the solid lines you made previously. These will complete the rotors themselves. Once you've cut each of them accordingly, fold along the dotted lines at the bottom of the fuselage. When this is done, fold along the vertical dotted lines. After this, fold the rotors down along the horizontal dotted line below them. After this is completed, your Tornado should appear as it does in the last photograph.

Step 4: Fuselage Folding and Taping

Fold your fuselage into a doughnut-like shape, then insert the edge of fuselage into the outcropping. Then apply tape to this area as shown.

Step 5: Flight

Due to its similar shape to the Hurricane, the Tornado has few differences in operation. Launches can be just dropping the aircraft or by launching the aircraft inverted with your hand (the technique is to jump while "high-fiving"). The latter is a better method if altitude is limited. Like the Hurricane, the Tornado may not descend vertically. Under certain circumstances, the Tornado may travel several feet laterally. If your Tornado is unstable, you may need to adjust the angles of the rotors. Enjoy!