Investigate water bottle rockets with controlled experiments

Compressed air pushes water through the nozzle; the escaping water pushes the rocket in the opposite direction. In Rocket Lab, students adjust a bottle rocket’s water fill, gauge pressure, nose cone, four fins and launch angle, predict the outcome, then examine a 3D flight and altitude graph. Record up to 12 tests with their complete settings and write a conclusion that cites the measured results. Download the experiment log as CSV.

Why more water does not always mean a higher flight

Adding water changes both the available exhaust mass and the volume of compressed air. It also increases launch mass. Keep all other settings fixed and compare water volumes to investigate this trade-off. Explore fin size and stability in a separate experiment, then compare the same rocket across Earth, Moon, Mars, Mercury and Titan.

A teaching model with explicit limits

The simulator uses ideal-gas expansion, water and air exhaust, constant gravity and quadratic drag. Other worlds are idealised comparisons that assume liquid water remains at room temperature. There is no wind, parachute, CFD or bottle-failure prediction. Results do not certify a design or establish a safe working pressure. Physical launches require teacher-approved equipment and procedures. Import your own Onshape STL nose cone and fins, check their fit and enter their printed mass. The model uses imported dimensions with simplified aerodynamics. Free-tool parts save in this browser on this device.

Free-tool designs and recorded experiments save in this browser on this device. Clearing storage removes them. Lesson activities use the lesson save channel. Inspired by teacher Aziz’s AquaRocket reference.

Explore airflow with the dragster wind tunnel, or browse all free simulators.