In this Instructables, you will learn how to make a quick & easy giant foam airplane! The design is based off one of the most simple paper airplanes.

Supplies

Supplies:

Foam board -- There are many type of foam boards. The ideal ones for this application would be light weighted foam boards with both side covered with a sturdy paper/plastic. The foam board we got from dollar store does not come with this extra layer of protection so we have to patch the connection part with tape after an afternoon of test flying. The best quality foam board/display board tend to be too heavy even though it offers good protection -- it is probably best quality for other projects but not in this case.
Croissant box (or other flexible plastic)
Duct tape, tape
Paper clips

Tools:

Scissors
Craft knife
Compass/Protractor

Step 1: Cut Foam to 3:4 Ratio

Cut the foam board to a 3:4 ratio.

Note: This isn't strictly necessary. We did this so the resulting board is of similar proportion to the paper we typically use to make the most common paper airplane.

Step 2: Cut Out Body

Mark the middle of the foam board (lengthwise).

Find the midpoint of one of the short sides. Cut out a line at 67.5 degrees from the side (or 22.5 degrees from the center line). Remove the triangles.

Step 3: Mark Angle for Wings

Use a compass or protractor to draw a line at the halfway mark between the middle and each wing.

Note: The diagram shows how to bisect an angle with a compass. If you have protractor, you can just measure 11 degree angle that will divide each angle into half.

Step 4: Cut Lightly to Fold Wings

Cut a light mark into the foam board along the wing lines you marked. Cut lightly into the middle from the bottom side.

Step 5: Fold

Fold out the wings and middle into a paper airplane shape. Wings on the two sides should be of mountain fold and body in this middle should be a valley fold. Reinforce the tip with tape as needed.

Step 6: Reinforce

We tried to sew fishing line into the foam to reinforce the airplane, but it cut through the foam after several flies.

Tape, or duct tape before sewing with fishing line, worked better.

Step 7: Plastic Triangle Support - Outside

Cut out small strips of plastic. Tape two triangles on the bottom side, near the front (see image), to reinforce the angle between wings and body.

Step 8: Plastic Triangle Supports Inside

Tape triangles of plastic to the inside of the plane to support the shape of our plane.

Step 9: Plastic Support Band

Tape a plastic support band across the front.

You can see some paper clips in the image-- those are added during test flies to adjust weights of different part of the plane.

Step 10: Testing & Adjusting

Try throwing the plane and adjust. The plastic triangle frame support we added turns out to be a very convenient way to adjust our plane for the aerodynamics. It is an extremely simple plane but it is interesting to play around with different settings.

For example, if it goes up and then down, the nose is too light. If it dives, the nose is too heavy. It could also go wobbly on the side and we later tried to extend the wings wider.

Be patient and you can get it right! We had fun testing out variations.