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Mr. Hayhurst's Quick and Easy Bottle Rocket
Much of this information was "borrowed" from Jake Winemiller of N.E.R.D.S. Inc. and observations of many rockets launched in competitions in which I have participated. Please treat it with respect. Also remember that this is only a start. You have to do the testing and the minor adjustments.
Problem
Create one bottle rocket that will fly straight and remain aloft for a maximum amount of time.
Materials
Two 2-liter bottles
One small plastic cone (athletic)
Duct Tape
Scissors
String
Manila Folder
Large Plastic Trash Bag
Masking Tape or Avery Paper reinforcement labels (you'll need 32/chute.)
Hole punch
Procedure
Cut the top and the bottom off of one bottle, so that the center portion or a cylinder remains. Tape the cylinder to another bottle to create a fuselage (a place to store the parachute).
 Get the manila folder; fins will be made from it. Cut three shapes out of the folded bottom in the shape that the diagram shows. Your fins will be triangular.
The next drawing indicates how the fin should look once folded.
Mark straight lines on the bottle by putting the bottle in the door frame or a right angle and trace a line on the bottle with a marker. Use these lines as guides to place the fins on the bottles. Make three fins and tape them on the rocket. Be sure that the fins are spaced equally around the rocket body. This can be achieved by using a piece of string and wrapping it around the bottle and marking the string where it meets the end. Mark the string and lay it flat on a meter-stick or ruler. Find the circumference of the bottle by measuring the length of the string to the mark. Once you know the circumference, then you can divide it by three to find the distances the fins should be separated.
Use the athletic cone to make your nose cone. Use fairly rigid scissors and cut the bottom square off of the cone. Depending upon your project's mass limitations, place a golf ball sized piece of clay in the tip of the cone. This will add mass to the cone and give the rocket/cone more inertia. Then, using scissors, trim the cone to make it symmetrical. (Hint: the diameter of the bottom of the cone should be a little wider than the diameter of a 2-liter bottle.
Attach the cone with string to the top of the other two-liter bottles so that it looks like the diagram. Tie a knot in the end of each piece of string to give it more friction and tape it using a piece of duct tape to the inside of the cone and to the inside of the rocket body.
Many students have trouble with their nosecone getting stuck on the top of the rocket and not coming off. This can be prevented by making a pedestal for the cone to sit on. It should be high enough up so that there is space between the cone and the top of the parachute compartment. You can make a pedestal out of the same material you will make the fins, the manila folder. Make three mini-fins, invert them and tape them on the rocket where the cone should sit. Making the Parachute
Don't forget a good parachute has shroud lines that are at least as long as the diameter of the canopy.
Lay your garbage bag out flat. Cut off the closed end. It should look like a large rectangle and be open at both ends. Lay down the bag on a flat surface and smooth it out.
Make sure the edges are perfectly lined up during each fold. Now fold it in half along the long axis.
Make a triangle with the base of the triangle being the closed end of the previous fold.
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