Development and Validation of a Tailsitter UAV for Efficient Hover and Forward Flight

This thesis presents the design, development, and testing of a tandem-wing tail sittereVTOL aircraft capable of seamless vertical takeoff and landing (VTOL) and efficient
forward flight without the mechanical complexity of tilt-rotor systems or added weight of
hybrid propulsion systems. The work began with preliminary sizing and aerodynamic
analyses in VSPAero to determine optimal wing incidence and aspect ratio for stable
cruise performance. A refined configuration was then reanalyzed using a higher fidelity
model to examine interaction effects between the front and rear lifting surfaces.
Structural design centered on a 3D-printed fuselage and modular wing components,
employing selective reinforcement and minimal infill strategies to achieve high strength
to weight ratio. Ground tests included tethered hover trials and free-flight evaluations
under manual pilot control, confirming stable roll, pitch, and yaw authority. Despite
incorporating fewer moving parts than traditional tiltrotors, the aircraft demonstrated
reliable vertical takeoff, controlled transitions, and steady forward flight at speeds
consistent with the tandem-wing’s lift requirements. Preliminary measurements showed
the design could achieve approximately eight minutes of flight while carrying a 0.5 kg
payload across an effective range of about 8 km. Collectively, these results indicate that a
tandem-wing tail sitter can offer a simpler, more efficient VTOL solution, laying
groundwork for future refinements and potential scaling to larger or more autonomous
platforms.