Types of water rockets

There are many types of water rockets depending on the materials they are made of, the number of boosters or stages they use and their type of thrust. This allows them (or not) to participate on different competitions.

According to the materials they are made of:

• Unreinforced bottle: They are water rockets made of plastic bottles without anything that could made them stronger or able to support extra pressure.
• Reinforced bottle: They are the opposite of  the unreinforced ones. They still being made of plastic bottles but use some materials like carbon fiber to make the pressure chamber stronger and able to support extra pressure. 
• Others: They are water rockets that aren't made of plastic bottles but other materials.

According to the number of boosters or stages they use:

• Single stage: They have just one pressure chamber and, during flight, they don't drop any part of them.
• Multiple stages: They are the opposite of the single stage ones. They have multiple pressure chambers and during flight they use them in different times (not simultaneously) and, when their are empty, they drop them.
• Boosters: They are very similar to the multiple stage ones. The difference is that they use their pressure chambers at the same time, usually with one in the center ones that its time is longer.

According to their type of thrust:

• Full thrust: They use pressure chambers with just one nozzle so they have a curvature on the diagram of their thrust.
• Dual thrust: They are very different compare to the full thrust. They use pressure chambers with more than one nozzle so they have a short period of time with a high thrust and then a short and longer period with lower thrust.