Loss-of-Control has been consistently deemed the primary contributor to air accidents globally. Systems capable of alerting pilots when impending control loss is predicted to occur have the potential to promote safer flight. To this end, the General Aviation Flight Lab at Wichita State University has developed an early warning guidance technology for loss-of-control avoidance that adaptively predicts an aircraft’s safe control envelope and warns of future impending entry into control loss given current aircraft state information. The prediction architecture analytically determines critical control deflections that would drive the aircraft into control loss n-seconds ahead of time, and the predicted control boundaries are presented to the pilot in real-time in the form of aural alerts and visual displays. Pilot-in-the-loop testing is conducted to validate the effectiveness of the prediction architecture and the guidance technologies, in an effort to determine whether the early prediction of control loss reduces the duration and magnitude of excursions outside of the safe flight envelope. The prediction architecture is implemented and evaluated through pilot-in-the-loop simulated flight testing in the three forms: an aural-only alert, a head-down display, and an augmented-reality head-up display using the Microsoft HoloLens. These are evaluated against the no-assistance condition, and results from testing indicate that the guidance technologies have the potential to reduce the occurrences and magnitudes of excursion of the safe flight envelope.