Rocket Science at Grangegorman
Rocket Science at Grangegorman
Programme: B.Eng.Tech. in Aviation Technology
Course code: DT011/1
Module: Thermo-Fluids Aircraft
No. of Students: 30
Lecturer: Eoin Murphy
Background: As part of the Thermo-Fluids module the students study basic physics of motion and flight, for example: Newton’s three laws of motion, calculation of acceleration, velocity, drag, kinetic and potential energy, and thrust. The physics of flight can be very exciting; however, the excitement can be lost in equations and diagrams in a classroom environment. This outdoor event brought the applications of the physics of motion and flight to life in a very real and exciting way. Colin Fitzsimons from the Irish Rocketry Society supplied the materials, motors and expertise for the rocket building, and was on-site on the day to provide safety supervision. Model rocket launching, contrary to common perception, is a relatively safe endeavour and Colin frequently visits primary and secondary schools to launch the same rockets as a valuable exercise to encourage children to study STEM (Science, Technology, Engineering and Maths) subjects, and eventually, follow STEM career paths. We needed a wide open space in which to launch the rockets and Grangegorman provided the perfect spot. A rocket is a relatively simplistic system to study in terms of energy, motion and the forces applied to it. As such, it is a great project for first year aviation students to undertake. The project itself dovetailed very well with the overall module learning objectives which included gaining an understanding of the basic properties of fluids and also, applying the equations of energy and motion to solve basic problems in flight.
Figure 1: Rocket on the Launchpad with Colin Fitzsimons from the Irish Rocketry Society at the launch controls.
Work Completed by Students: The students used the rocket-motor manufacturer’s thrust profile data and excel to calculate the theoretical values of acceleration, velocity, drag, altitude, potential and kinetic energy throughout the flight at a given time interval. The actual altitude achieved by the rockets was recorded on the day using apparatus designed by the students (sample shown in figure below) and some trigonometry, and this was then compared with the theoretical values. All the students completed a report on their individual rockets which included a brief description of the history of rockets throughout the ages, explanations of the theory involved, step-by-step breakdown of their calculations, results obtained and conclusions drawn.
Figure 2: Successfullly launched rocket with parachute deployed.
Feedback: The students themselves felt that this project was very worthwhile as it brought some excitement to the class. Seeing a problem with their own eyes is much better than trying to visualise a description given in a typical engineering textbook. Also, it honed their ability to use the equations taught in class by applying them to a simple engineering system. In addition by using excel to calculate their theoretical results, they improved their soft skills which should stand to them further on in the course. Finally, each student got to keep their rocket as a memento, unless it got stuck in a tree!
Figure 3: Colin Fitzsimons (Irish Rocketry Society) and the class of DT011/1 proudly displaying their rockets on the playing grounds at Grangegorman on a cold Spring morning.
Figure 4: Sample apparatus used to observe the maximum angle achieved which in turn using trigonometry could be used to calculate the maximum altitude of the rocket.
Figure 5: Typical thrust profile of a model rocket motor.
For further information, contact Eoin Murphy eoin.murphy@dit.ie
