Introduction: Roto-copters

About: Science City At Home content is sponsored by MRIGlobal. Internationally awarded for “Great Visitor Experience” by ASTC and regionally voted “Favorite Family Friendly Attraction” by Visit KC, Science City one o…

There are a lot of forces working together to make a bird, aeroplane, or helicopter fly. Making and testing a simple paper vehicle called a Roto-copter will help you experiment and learn the principles of flight.


The principals of flight are the forces of lift, weight, thrust, and drag that work to keep a flying object in the air.

Lift: The lift force acts upward against weight and is caused by moving air passing over and under wings.

Weight: The weight force is the gravitational force that pulls everything toward the Earth. This is a downward force.

Thrust: The thrust is the force that moves an object forward and can be provided by a power like plane engines or bird muscles.

Drag: Drag opposes thrust and is caused by air resistance that acts in the opposite direction to the motion.


  • Printout of PDF
  • Scissors
  • Tape

Step 1: Download and Print PDF of Roto-copters

Step 2: Cut Along the Solid Lines. the Dotted Lines Are for Folding.

Step 3: Fold a Toward You and B Away From You.

Step 4: Fold C and D So They Overlap.

Step 5: Fold the Bottom Tab, and You May Put a Small Piece of Tape in Place If You Wish.

Step 6: Drop Your Roto-copter From a Height and Observe. If It Does Not Move Like a Roto-copter, Adjust Blades a and B Until You Get the Results You Want.


When the roto-copter falls, air pushes up against the blades, bending them up a little. When air pushes upward on the slanted blade, some of that thrust becomes a sideways push. Each blade is getting the same push, but in opposite directions. The two opposing thrusts work together to make the roto-copter spin. Thrust is one of the main principles of flight and in this case is generated by propeller, which flaps A and B become.