Introduction: Intro

In this project, you will learn how to build a bottle rocket, including a return system and parachute.  The rocket is powered by water pressure, and will be launched into the air.  Once in the air, your rocket should deploy the parachute and tennis ball, which should fall to the ground slowly.

Step 1: Get the Materials.

To complete this project you will need:

*Two 2 L. empty soda bottles
*One 39 gallon garbage bag (Be sure to bring extra because the parachute is a little tricky)
*One standard tennis ball
*Duct tape
*Cardboard or another sturdy material (for fins)
*One pair of scissors
*String (Not yarn or twine)

Step 2: Prepare Bottles

Take your TWO 2 liter bottles (they should both be empty.)  Cut one of these bottles approximately 21.5 cm from the bottom.  This will be the nose of the rocket.  The other one should be left in tact and will be the main body of the rocket (the fins will be attached  to this bottle.)  The uncut bottle will be used upside down, with the open end being the bottom of the rocket.

Step 3: Cut Fins

In order to allow the rocket to go as high as possible, cut FOUR right triangles that need to be the same size.  The triangles should measure approximately 11.5 cm by 15.5 cm.  Once finished, use duct tape to attach the wings to the bottle which is uncut.  The wings should be an even distant apart, as well as even height,  If they are not both, than the rocket may not fly correctly.

Step 4: Making the Parachute

To make the parachute, one 39 GALLON garbage bag should be used.  Slits should be made of an equal length on either side of the bag, and then the length of the bag should be cut, leaving about 1/2 of the full bag as the parachute.  Strings should be attached on either side of the parachute, and it should end up looking like a pouch.

Step 5: Attach Tennis Ball

The next step is to attach ONE  standard tennis ball to the parachute using string.  First, a hole must be cut  in either side of the tennis ball using the scissors (or another sharp object such as an Exacto Knife), each hole directly opposite from the other one.  The strings should be strung from the parachute, through the ball, and then knotted at the other end of the tennis ball to keep them in place.

Step 6: Test Parachute

Test your parachute by dropping it from a height, however, make sure that you are able to retrieve the parachute after you drop it.

Step 7: Put It All Together

Fold the parachute and place it in the nose of the rocket (the bottle that was cut).  Place the nose on top of the uncut bottle with the attached fins.  It is important to remember that the open end of the uncut bottle should be the bottom of the rocket.

Step 8: Launch Your Rocket

Finally, using an air pump, and a launching apparatus, launch your rocket.  It should go pretty high, and once it reaches its maximum height, the nose should detach itself from the rest of the rocket, allowing the tennis ball and parachute to deploy.  It should take around 20 seconds for the parachute to full reach the ground.

Step 9: Record Data

Record data including how long it took for your parachute to reach the ground, how high your rocket went, and how long it took for the parachute to deploy.

Step 10: Finish

You have now learned how to build a bottle rocket! Good luck!