Role Overview: We are seeking an experienced Principal GNC Systems Engineer who will own the guidance, navigation, and control architecture for the Massed Modular Aircraft (MMA) program, with particular emphasis on multi-aircraft interoperation - the behaviors, algorithms, and simulation environments needed to design, verify, and validate how multiple MMA air vehicles fly, coordinate, and interact with one another in shared airspace or mission scenarios. This role requires hands-on experience building and using 6 degree-of-freedom (6DOF) simulations involving multiple interacting aircraft, not just single-vehicle GNC development, and is responsible for ensuring the platform''s GNC design supports safe, predictable, and effective behavior at the scale and density implied by a "massed" aircraft concept.