I found this project in “Make: Technology on your time” and give them credit for this project.
Step 1: Materials
Paper Water Bomber
(Ewan Spencer) Directions followed, made, # posted by N. Weller
Materials needed: Paper, scissors, water, & a target
Step 2: Part 1: Making the Body
1) 1.1) If needed cut your paper to make a length/width ratio of 2:1 (if the length is 20 the width needs to be 10 etc).
2) 1.2) At one end, fold each corner down to the opposite edge to make two 45o folds, and then unfold, to make an X crease. Turn over and fold the top edge down to bisect the X.
3) 1.3) Turn over again, push the edges in, and flatten the paper so there is a point at the top. Fold at the bottom edge of the triangle.
4) 1.4) Fold each entire top corner down (45o) along the centerline.
5) 1.5) Unfold just the back corners and leave the front corners folded down.
6) 1.6) Invert the crease you just made on the back corners, so they lie underneath and inside, making the top pointy again.
Step 3: Part 2: Make the Cargo Bay
1) 2.1) Fold the side of each flap to touch the centerline.
2) 2.2) Fold the bottom point of each flap to touch the same centerline.
3) 2.3) Fold each of the side corners of the diamond back to touch the centerline behind. Fold the top and bottom corners in front to touch the centerline. Unfold all four folds so that there are now four visible creases.
4) 2.4) Crease the wings to line up with the edges of the cargo section(even with the side creases of the diamond).
5) 2.5) Fold the flapping bottom points (made in step 2) diagonally and tuck them into the pockets of the side flaps (made in step 1).
6) 2.6) Blow the nose of your plane up while, at the same time, gently pulling to inflate the cargo section.
Step 4: Part 3: Loading and Bombing
1) Fill the cargo section with water by pouring carefully into the hole in the front (you may choose not to completely fill it if you want a lighter plane).
2) Throw the loaded plane at your target (if you are aiming at someone you might want to wait until our target is not looking).
3) Repeat parts 1, 2, & 3! Enjoy!!!