Cessna Consternation: Safely Encountering Microbursts in Trainer Aircraft

Abstract

This thesis focuses on the design for an autopilot able to aid in landing during microbursts, weather events that can complicate landing approaches due to large wind shears. If an aircraft traverses through the center of a microburst, it experiences an almost instantaneous change from a headwind to a tailwind that can result in total wind shear exceeding 100 kn. Aircraft on approach to land face particular issues with this event due to the microbursts' increased strength near the ground, combined with the aircraft's low speeds and altitude, causing several well-documented airline crashes. A design for an autopilot of a Cessna 172 trainer aircraft is presented that enables the aircraft to safely land despite encountering a microburst near the airport. This autopilot allows the aircraft to be pushed by the high winds away from the microbursts' center, maneuvering around the strongest winds before returning to alignment with the runway's approach. The aircraft is modeled and its aerodynamic data collected to allow for a high-fidelity simulation of this movement to serve as a pedagogical tool in microburst evasion for student pilots. The open-source flight simulator FlightGear is mapped to the simulation for viewing and validation of suggested evasion methods. The autopilot suggests not fighting heading, allowing the wind to push the aircraft laterally. The success of these suggestions were verified in manual control tests in the simulated environment.