In this section, we will test different modifications to improve flight characteristics, some adjustments will improve, and some may not, it all depends on what you want to achieve, i.e., fast flight, extra distance, longer flight time.
At this point, you can choose to either keep reading about basic aerodynamics or if you prefer just to get started with the hands-on stuff, then scroll down to the paper airplane pictures below.
Four forces are acting on an airplane: lift, weight, thrust, and drag. I will briefly explain each of them and then, after that, explain how they work together in flight.
- LIFT – In a typical airplane lift is generated by the wings, the shape and size of the wings determine the amount of lift.
- WEIGHT – This is the force that pulls down on the airplane, also known as gravity.
- THRUST – This is the force the propels the airplane forward. In a typical aircraft, this is usually a propeller or a fan which displaces enough air particles to cause forward motion. On a paper airplane, this force only occurs at the start when you throw the paper airplane, i.e., your hand is providing the initial thrust to accelerate the paper plane forward, I will explain below how the paper airplane continues to fly.
- DRAG – This is the force that acts in the opposite direction to thrust, so anything on the airplane that interferes with smooth airflow will cause resistance to forward flight, it is the force that stops the aircraft from flying forward.
So for an airplane to fly it needs a wing that is big enough to carry its weight, it needs to be of a shape and size that fits the purpose of the airplane. The wing will have a streamed line shape, which is thicker at the front than the back, and this creates different air pressures, which aids in the production of lift. The airplane needs a source of thrust to overcome the forces of weight and drag, the effect of weight(gravity) on a paper airplane is constant. The initial throwing action of the paper plane will generate the acceleration force(thrust). Still, once that is gone, the only force that can provide acceleration and airflow over the wings to generate lift is gravity. With that in mind, the more height you have above the ground at the start, the longer it will take your paper airplane to reach the ground.
The other force hindering the flight of your plane is drag, so the more streamlined you make your airplane, the less resistance it will generate. If you would like a more detailed and technical explanation of aerodynamics, I’ve created a link here for you to follow. In summary, modifying the size and shape of the paper airplane will cause different flight characteristics.
Below we will find out how by adjusting the size and shape of the wing. We will add weight to the paper plane and observe the effect, and we will also see what effects throwing techniques have on the flight of the paper plane. The pictures below will show different ideas for modifying your paper plane to improve flight.
After each modification, fly the plane and see what happens.
These designs and modifications are just a start, so let your imagination fly and see where it takes you.
Fold the nose. It makes the airplane more robust.
Does it fly better or worse?
For the next experiment, we will use scissors (you can do this with your hands if you don’t have any).
Cut as shown on the picture to create a rudder.
Fold it up, as shown.
Does this give the plane more or less stability?
For the next experiment, we will use a pencil and sticky tape or a tiny amount of blue tack.
This experiment will explore what effects shifting the Center of Gravity has on an airplane.
Place the pencil at the front of the plane as shown.
What did this do to the flight path of the plane?
Place the pencil at the back of the plane, as shown.
What did this do to the flight path of the plane?
Place the pencil in the middle of the plane, as shown.
Does this create a more stable flight path?
Now we can understand the importance of correctly loading a real airplane.
Now let us increase the surface area of the wings to see what effect this will have on the flight path of this particular design.
Does this make your airplane fly better or worse?
Let’s add winglets.
Does it make your airplane fly better or worse?
Let’s add a paper clip to the front.
Has this improved how the airplane flies?
You will find that sometimes by making specific design changes, you will have to add another variation to bring the aircraft’s flight path back to a balanced state and have a more controllable paper airplane.
By now, your airplane probably looks a little worse for wear.
Why not make a new one, using the concepts you have learned.
Try a different paper plane design, and once again, let your imagination fly.