Paper airplanes
Paper airplane flight
Paper airplane flight: understand lift, drag and gravity. Adjust wing trim. Compare 5 baseline flights with 5 flights after one small wing change.
Paper airplanes guide80 gsm A4 or LetterTested flight notes
Lift, drag, thrust and gravity
- Lift
- The aerodynamic force perpendicular to the flight path. The wings redirect air and develop a pressure difference as they move through it.
- Drag
- Air resistance opposing motion through the air. It acts along the flight path in the opposite direction.
- Thrust and launch
- A powered airplane has engine thrust. Your hand pushes a paper plane during the throw; after release it glides without continuing thrust.
- Gravity (weight)
- The downward force on the plane. In a steady glide it descends while lift and drag balance its weight.
Trim: make small adjustments
Trim is the adjustment that lets a plane settle into a steady flight. Start with equal wings. If the dart dives, bend both rear edges upward slightly. If it rises sharply and then drops, ease them back down.
Change a little at a time and throw again. A lopsided wing or an uneven crease can send the plane into a turn.
Classroom experiment: does trim change distance?
You need one dart, a tape measure, a launch-line marker and a results sheet. Use a clear indoor lane, with everyone behind the thrower.
- Predict whether a small upward bend in both rear wing edges will increase or decrease the distance.
- Make 5 baseline flights. Keep the same thrower, release height and launch direction. Measure to the first landing and write down every result.
- Bend both rear wing edges upward by the same small amount. Change nothing else, then make 5 more flights.
- Average the distances in each set. Compare the averages and note any dives, turns or stalls.
- Flatten the edges and repeat the baseline. Discuss whether the change in flight follows the trim, or whether the throws themselves changed.