Project Zephyrus: Developing a rapidly reusable high-altitude flight test platform

Reusable, inexpensive, and rapid testing of payloads in near-space conditions is an unfilled niche that could speed development of flight-ready projects. With growing availability of commercial off-the-shelf (COTS) hardware and open source software, high-altitude ballooning (HAB) has become a viable option for rapid prototyping of ideas in near-space conditions. A product of the Jet Propulsions Laboratory's (JPL) collaborative Innovation to Flight (i2F) program, the Zephyrus system is a proposed HAB solution for high-altitude testing and atmospheric observation, a cheaper and easy-to-use alternative to traditional HAB systems. The Zephyrus system permits testing of small-to mid-sized instruments in the upper atmosphere (approximately 35,000 m maximum altitude) using a reusable common architecture. Over the summer of 2017, the i2F team demonstrated all of these key features of the Zephyrus platform via four test flights. Zephyrus I, II, III, and IV were successfully launched, tracked, and recovered over groundtracks of up to approximately 50 km and altitudes of approximately 30,000 m by a team averaging eight individuals, while accomplishing a majority of the intended science. This included a turnaround time of less than two weeks between two flight tests with differing instrumentation. Lessons from the Zephyrus I flight were successfully used in the Zephyrus II flight to speed up launch time and operations procedures (e.g. rigorous pre-launch preparation). Likewise, the Zephyrus III flight brought the cost of relaunching a mid-sized payload to 28,500 m down significantly. Many diverse instruments and experiments were tested during the Zephyrus missions (e.g. inflatable origami reflectors, flexible solar panels), demonstrating the system's versatility. From concept to first flight of Zephyrus I in just five weeks, followed by turnarounds as short as two weeks, the team demonstrated that it is entirely possible to bring to bear cost-effective, hobbyist HAB techniques in meaningful high-altitude testing using a new reusable test platform.