FET Adaptive Morphing Small-Scale and Model Aircraft Demonstrator

This proposal presents the FET Adaptive Morphing Small-Scale and Model Aircraft Demonstrator, a staged fixed-wing experimental programme designed to test Frequency Envelope Traversal through controlled aerodynamic shape adaptation. The proposed aircraft retains a conventional and structurally valid fixed-wing architecture, including a rigid central fuselage, continuous primary wing spars, rigid wing-root structures, conventional control surfaces, manual pilot authority and a safe reference airfoil configuration. An additional FET assistance layer uses distributed pressure, strain, deformation, inertial and aircraft-state sensing to evaluate whether the current wing geometry remains compatible with the surrounding airflow. When changing aerodynamic conditions justify adaptation, selected wing panels may make small, bounded changes to camber, trailing-edge curvature, local twist, thickness or wingtip geometry. The system is intended to remain in its current natural admissible aerodynamic state and move only when changing airflow requires another admissible configuration. The purpose is not to replace conventional controls, but to investigate whether controlled structural adaptation can reduce disturbance and corrective demand before large control-surface corrections become necessary. The proposed wing architecture consists of a rigid load-bearing spar and wing-root structure surrounded by compliant aerodynamic sections. Each half-wing may include an inboard morphing panel, mid-span morphing panel, outboard morphing panel and morphing wingtip panel. Initial actuation may use servo-driven tendons or cables because they provide a simple, measurable and comparatively low-cost starting point. Later versions may investigate pneumatic cellular systems, compliant structures, distributed actuators or smart materials. The programme progresses through digital modelling, bench-scale wing construction, controlled-airflow testing, conventional aircraft validation, passive FET operation, limited active morphing, independent left-right adaptation, multi-panel control, degraded-mode testing and later transfer to small research UAVs and larger experimental aircraft. The proposal explicitly separates three experimental configurations: A fixed conventional aircraft. A conventionally adaptive aircraft using predetermined morphing responses. An FET adaptive aircraft using compatibility evaluation, admissibility gating and distributed shape selection. This structure separates the aerodynamic benefit of morphing hardware from any additional benefit provided by the FET decision architecture. The aircraft must remain safely controllable when FET is disabled, unavailable or operating in a bounded degraded condition. Pilot and conventional flight-control authority remain primary, while FET operates as a subordinate assistance layer. The proposal does not claim new aerodynamic laws, new propulsion, elimination of conventional control surfaces, guaranteed performance improvement or immediate suitability for passenger aviation. It defines a practical, scalable and falsifiable pathway for testing whether a conventionally controllable aircraft can reduce corrective burden by fitting its wing geometry more closely to changing airflow.