Kingston’s students normally enjoy their summers soaking up the sun, travelling and visiting back home – but a select few, including Ben Edgley and Chris Walker, spent theirs designing, building and launching water rockets for their Astronautic Engineering degree 2nd year group project.
The group were tasked to design and construct a water rocket that could reach a height of at least 50 metres. To pass the assignment, they had to use their knowledge of rocket engines to design various concepts, predict performance, construct prototypes and finally launch. What’s more, they had to demonstrate project management skills such as organising meetings, delegating tasks and good time management.
“A water rocket uses the same principles that NASA uses to send astronauts to the moon,” advised Academic Mentor Jack James Marlow. “High pressurised water acts like a fuel and produces a thrust force when forced through a nozzle. This thrust force produced by the expelled high velocity water is what gives the rocket its acceleration upwards. The pressure of the rocket is crucial and had to be calculated from the theory learnt in class, as this determines the materials used and height of rocket, therefore a trade- off analysis is needed”.
The group constructed their single stage tall rocket from several coke bottles held together with industrial glue and added fins made from reinforced plastic for stability. Ben and Chris then started work to upgrade and improve the performance of the rocket, hoping it would reach a height of over 100 metres. After a month’s work – and waiting for parts to arrive from America – the rocket was finally ready to fire!
The launch took place on a sunny day in July. The rocket were placed on a launch pad (constructed by the students) and pressurised to the required value – plus a micro video camera and altimeter (to record the height reached) were attached. The release mechanism consisted of a simple system of cord and hosepipe connectors which allowed for disconnection from a safe distance.
The countdown began, and when instructed, the rocket was released. A loud noise – and a lot of water spray later – the bottle rocket flew off the pad at high speed to whoops from nearby spectators. The day went perfectly except for the failure of the parachute recovery system which caused the bottle rocket to fall nose down into the ground.
First year student Alex Pickard, who helped out on the day, said “The rocket flew up and we were all clapping and cheering then realized the parachute had not deployed. It is not a major setback as we can repair it for use next term”.
Graduate Jack James, who had overseen the projects from the start, concluded, “This project really allows the students to get “hands-on” with the task, generating invaluable workshop experience for the student, which greatly enhances their engineering skill set. This project really does compliment the classroom taught part of the module, as it demonstrates the fundamentals of rocket performance on a safe scale.”