This is my first serious rocket which features a 4L dual bottle pressure chamber and a Optical Apogee Parachute recovery system. It’s primary mission was to be a test and tuning platform for Robinson couplings and the Optical parachute circuit. The rocket was also a key part in helping to understand how to make rockets fly straight and stable.

The bottles are joined using a Robinson coupling. The first few pressure tests leaked air really badly, but through refinement using bicycle inner tubing to create an air tight seal, it was then capable of holding around 40-50psi with only slight leakage.

The massive breakthrough came with the idea to use steal washers between the nut and the inner tube, this allowed us to test the bottles up to 120psi with no leakage, at which point we lost our nerves.

Although the rocket made many low pressure flights, including many hand thrown launches to experiement with stability, the rocket only really ever made 4 real launches. On all four launches, the parachute deployed on time and apart from the last launch, brought the rocket safely back to earth. On the last launch the rubber bands acting as a shock cord broke and the rocket left the parachute floating around in the sky whilst it plumeted down with a thud.

As it was a development rocket however all was not lost, we learnt that we needed a bit of safety string in case the rubber bands ever broke. We also dissasembled the rocket and used the remaining parts to build our next rockets.

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