This paper presents the flight test verification and validation of a novel multi-reference longitudinal and lateral -directional guidance logic across multiple autonomous aircraft with distinctly different dynamics. L.sub.N guidance logic takes advantage of tracking a span of multiple references across the desired track, similar to an insect's compound eyes, allowing for a much higher temporal resolution and more predictive and anticipatory guidance logic. The stability of L.sub.N guidance algorithms is investigated using global Lyapunov stability theorems and its stability is proved. Validation and verification flight tests of L.sub.N lateral-directional guidance logic demonstrate superior tracking performance adaptability of this novel method compared to other methods such as L.sub.1 or L.sub.2.sup.+. The L.sub.N longitudinal guidance is newly developed in this paper and shows excellent altitude tracking capabilities and similarly scalable. Statistical analysis of multiple flight tests involving varying environmental states with three unique aircraft and different advanced flight controllers are shown to prove the capabilities, robustness, and consistency of L.sub.N guidance. Keywords UAS * Flight test * Autonomy * 3D guidance * Predictive and adaptive guidance * UAM * Lyapunov