# Water Rocket

### By: William Cross

1. Define the Problem. What need or want must be met by the solution?

Make a rocket out of a 2 liter bottle and make it fly with water and air.

2. Brainstorming. In the space provided, sketch three possible solutions to the given problem. Remember to be creative!

3. Research and Generating Ideas

In the space below, document your research. Be sure to include proper citations at the end of your notes.

Notes:

• German V-2 rocket which became the first long-range ballistic missile to see combat use
• V-2 rocket used a liquid fuel consisting of alcohol and liquid oxygen to carry a 1,650 pound load up to 225 miles
• skilled US Air Force pilot by the name of Chuck Yeager flew the Bell X-1 at a speed of 807.2 mph with an altitude of 45,000ft
• Bell X-1 flight became the first recorded manned supersonic flight
• Supersonic flight now meant humans could fly faster than the speed of sound
• Russia was the first to use a rocket to put a satellite into space
• Soviet Union was the first to put a man, Yuri Gagarin, into space
• On May 5, 1961 Alan B. Shepard was the first American astronaut
• July 1969, Apollo 11 astronauts - the first humans to walk on the moon - were successfully launched with a Saturn V rocket.
• their last launch on July 15, 1975. On that day a Russian spacecraft carrying three cosmonauts lifted off seven and a half hours before an Apollo spacecraft was launched carrying American astronauts
• Mass = density x volume
• volume = thickness x width x length
• weight = mass x gravity
• momentum water = mass water x velocity water
• mass water x velocity water = mass rocket x velocity rocket
• The center of gravity is the "balance point" of the rocket
• The first is a lawndart
• The second passive recovery is tumbling
• The third is backsliding
• Recovery system work area called Deploy Volume and Tube Volume
• Thrust is a force that produces lift-off, or upward movement of a rocket
• Thrust acts through the center of gravity and must exceed weight in order to move the rocket off of the launch pad
• Newtons 3rd law - For every action, there is an equal and opposite reaction
• The purpose of Thrust is to maximize rocket velocity and we can accomplish this by maximizing the velocity of the ejected water or minimizing the mass of the rocket
• The variables that you can actually control to affect the velocity of the ejected water are bottle pressure, water volume, and bottle size
• weight = mass x gravity
• momentum water = mass water x velocity water
• mass water x velocity water = mass rocket x velocity rocket
• The center of gravity is the "balance point" of the rocket
• The first is a lawndart
• The second passive recovery is tumbling
• The third is backsliding
• Recovery system work area called Deploy Volume and Tube Volume
• Thrust is a force that produces lift-off, or upward movement of a rocket
• Thrust acts through the center of gravity and must exceed weight in order to move the rocket off of the launch pad
• Newtons 3rd law - For every action, there is an equal and opposite reaction
• The purpose of Thrust is to maximize rocket velocity and we can accomplish this by maximizing the velocity of the ejected water or minimizing the mass of the rocket
• The variables that you can actually control to affect the velocity of the ejected water are bottle pressure, water volume, and bottle size
• area at the nose of the rocket is equal to the surface area at the tail of the rocket
• A recovery system is part of the rocket that allows the rocket to safely return to earth after launch
• The standard (lawndart), tumble, and backslider recovery systems are considered passive designs because the rocket's return to earth is largely based on the same principles of stability that took the rocket upwards
• Recovery system work area called Deploy Volume and Tube Volume. If the tube volume (what you have actually designed) is less than the required deploy volume, then the parachute will not deploy.
• You should design your recovery system to minimize the falling velocity of the rocket

4. Identifying criteria and specifying constraints. What are the criteria and constraints?

Materials List:

• 2 liter bottle
• parachute
• clay
• cone tube
• cone transition
• water
• air
• foam board

5. Exploring possibilities

Reflect on your brainstorm ideas and research notes. Generate any additional designs which you feel meet the criteria and constraints in the space below.

The reason I made the transition length on the first design was for weight. I put it longer on the other ones to make the static margin. Another thing is that the nose tube length longer on the first design so that the parachute would deploy because it wouldn't with the transition cone being so short.

6. Selecting an Approach

a. Enter the constraints of the project in the first column.

b. Score each sketch for each constraint. + = 3 pts., √=2 pts., - = 1 pt. c. Total the columns and circle the highest score.

7. Developing a Design Proposal

Take your highest scoring sketch and create working drawings (sketches with dimensions, so that you could build your project). Attach your working drawings to this sheet.

8. Making a model or prototype