A water rocket is a type of model rocket which uses water as its reaction mass. The water is forced out by a pressurized gas, typically compressed air. Like all rocket engines, it operates on the principle of Newton's third law of motion. Water rocket hobbyists typically use one or more plastic soft drink bottle as the rocket's pressure vessel. A variety of designs are possible including multi-stage rockets. Water rockets are also custom-built from composite materials to achieve world record altitudes. The thrust of the rocket will be obtained by the water that is forced out by the pressurized gas.
In this event, the participants need to come up with a fabricated water rocket. The maximum distance travelled by the rocket and the time for which the rocket stays in flight will be the judging criteria to decide the winner.