Document Type



Master of Science


Mechanical Engineering

First Adviser

Grenestedt, Joachim


A high-altitude dynamic soaring unmanned aerial vehicle (UAV) called JetStreamer has been designed and built in the Composites Lab of Lehigh University. A small jet engine will be used to bring this UAV up to the jet stream. The small jet engine is lighter than a piston engine and may be more efficient at high altitude. This makes it particularly attractive for Jet Streamer flying over 10,000 m. However, the installation of the jet engine could be a challenge due to the limited space and complicated structure reinforcement especially when there is retractable motion involved to reduce the drag. The purpose of this work is to design and manufacture a retractable jet system which can be installed inside the fuselage. A parallelogram mechanism was used for achieving the retractable motion. It is driven by a worm and gear with power from a 6 rpm motor and automatically locks in position when the motor stops. The main structure of the system was fixed on two bulkheads mounted inside the fuselage. The whole system has been made and installed inside a simulated carbon fiber fuselage right on the target location. The shift between retracted and extended position was steady even when the load factor was up to 10 caused by gusts. The results indicate that this retraction system satisfies the design requirements.