The future of fixed-wing autonomous aircraft operations depends on the availability of an appropriate UAS testbed. The testbed must be accessible: relatively inexpensive and easy to come by, without requiring long shipping delays from small international companies. It must be reconfigurable to accommodate the vast range of different sensor packages, payloads, use-cases, and flight characteristics needed to accommodate a broad variety of autonomy operations. It must be easy to fix or find replacement parts that will inevitably break during rigorous testing and it must accommodate safety analysis on-board with a deep understanding of the aircraft's design. Yet no previous fixed-wing UAS meets this need. Therefore, we contribute the first completely open-source (in both hardware and software) fixed-wing UAS, designed for reconfigurability and accessibility of broad audiences from researchers to high school students.