Launch of a simple water rocket

The Iapetus was one of our first rockets that wasn't just a bottle. Though it's design was very crude it flew pretty well. The rocket consisted of two 2-liter Pepsi bottles (one bottle was cut apart to make the nose cone and the cylindrical fin), four pieces of wire, some duct tape and a small earth-filled bag as nose weight.

The rocket is being mounted on the launcher.

Final check

Pressurizing the rocket


It flew pretty high...

Last shot before impact

The "landing" was a bit ungentle, but after readjusting the fin and fixing the wires with some additional tape the Iapetus flew again flawlessly. Please note the "mist" inside the bottle: Upon liftoff the pressurized air expands rapidly and therefore cools down which makes the water vapor condense.