To date, there are hundreds of Advanced Air Mobility (AAM) vehicles under development. Most of these vehicles differ significantly from traditional airplanes and rotorcraft when it comes to configuration and handling qualities. Handling qualities for traditional airplanes and rotorcraft are often very predictable. All AAM concepts currently under development feature some sort of fly-by-wire flight control system. Regulatory agencies already have decades of experience with certifying fly-by-wire airplanes. Fly-by-wire rotorcraft have proven to be significantly more difficult to certify and several flight test accidents have occurred as a result of handling qualities deficiencies, or “cliffs”. To ensure the safe and timely certification of AAM vehicles, methods to predict these handling qualities cliffs with reduced risk for test pilots is necessary. This thesis focuses on the development of two such methodologies. The first methodology is fully automated and predicts the forces and moments required for a vehicle to perform a given task, which are then compared with the envelopes of attainable forces and moments as a function of the vehicle’s state. While this methodology can predict when an aircraft would run out of control authority during a task, it’s capability to predict a wider range of handling qualities cliffs due to factors such as dynamic instability and pilot-in-the-loop effects is very limited. The second methodology displays the aircraft’s flight envelope in real time to the pilot as a function of the aircraft’s state and displays the location of the aircraft with respect to the boundaries of the envelope. This could alert pilots to any upcoming handling qualities cliffs and help prevent loss of control accidents during flight testing.
","abstract_html":"<p>To date, there are hundreds of Advanced Air Mobility (AAM) vehicles under development. Most of these vehicles differ significantly from traditional airplanes and rotorcraft when it comes to configuration and handling qualities. Handling qualities for traditional airplanes and rotorcraft are often very predictable. All AAM concepts currently under development feature some sort of fly-by-wire flight control system. Regulatory agencies already have decades of experience with certifying fly-by-wire airplanes. Fly-by-wire rotorcraft have proven to be significantly more difficult to certify and several flight test accidents have occurred as a result of handling qualities deficiencies, or “cliffs”. To ensure the safe and timely certification of AAM vehicles, methods to predict these handling qualities cliffs with reduced risk for test pilots is necessary. This thesis focuses on the development of two such methodologies. The first methodology is fully automated and predicts the forces and moments required for a vehicle to perform a given task, which are then compared with the envelopes of attainable forces and moments as a function of the vehicle’s state. While this methodology can predict when an aircraft would run out of control authority during a task, it’s capability to predict a wider range of handling qualities cliffs due to factors such as dynamic instability and pilot-in-the-loop effects is very limited. The second methodology displays the aircraft’s flight envelope in real time to the pilot as a function of the aircraft’s state and displays the location of the aircraft with respect to the boundaries of the envelope. This could alert pilots to any upcoming handling qualities cliffs and help prevent loss of control accidents during flight testing.</p>","abstract_has_math":false,"creators":["Spier, Louis"],"institution":null,"degree_name":"Master of Science in Aerospace Engineering","degree_level":"Thesis - Open Access","degree_discipline":"Aerospace Engineering","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-04-01T07:00:00Z","date_published":"2024-04-01T07:00:00Z","updated_at":"2026-07-27T19:26:16Z","subjects":["Advanced Air Mobility","Urban Air Mobility","AAM","UAM","eVTOL","Certification","Handling Qualities","Flight Envelope","Flight Test","Flight Controls","Aeronautical Vehicles","Navigation, Guidance, Control and Dynamics"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://commons.erau.edu/edt/812","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Spier, Louis"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2025-12-31T08:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Aerospace Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - Open Access"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science in Aerospace Engineering"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Advanced Air Mobility","Urban Air Mobility","AAM","UAM","eVTOL","Certification","Handling Qualities","Flight Envelope","Flight Test","Flight Controls","Aeronautical Vehicles","Navigation, Guidance, Control and Dynamics"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://commons.erau.edu/edt/812"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["To date, there are hundreds of Advanced Air Mobility (AAM) vehicles under development. Most of these vehicles differ significantly from traditional airplanes and rotorcraft when it comes to configuration and handling qualities. Handling qualities for traditional airplanes and rotorcraft are often very predictable. All AAM concepts currently under development feature some sort of fly-by-wire flight control system. Regulatory agencies already have decades of experience with certifying fly-by-wire airplanes. Fly-by-wire rotorcraft have proven to be significantly more difficult to certify and several flight test accidents have occurred as a result of handling qualities deficiencies, or “cliffs”. To ensure the safe and timely certification of AAM vehicles, methods to predict these handling qualities cliffs with reduced risk for test pilots is necessary. This thesis focuses on the development of two such methodologies. The first methodology is fully automated and predicts the forces and moments required for a vehicle to perform a given task, which are then compared with the envelopes of attainable forces and moments as a function of the vehicle’s state. While this methodology can predict when an aircraft would run out of control authority during a task, it’s capability to predict a wider range of handling qualities cliffs due to factors such as dynamic instability and pilot-in-the-loop effects is very limited. The second methodology displays the aircraft’s flight envelope in real time to the pilot as a function of the aircraft’s state and displays the location of the aircraft with respect to the boundaries of the envelope. This could alert pilots to any upcoming handling qualities cliffs and help prevent loss of control accidents during flight testing.
"]},{"key":"dc:title","label":"Title","values":["Prediction of Handling Qualities Deficiencies for Advanced Air Mobility Aircraft"]}]}],"canonical_facts":{"dc:creator":["Spier, Louis"],"dc:date.available":["2025-12-31T08:00:00Z"],"dc:description.abstract":["To date, there are hundreds of Advanced Air Mobility (AAM) vehicles under development. Most of these vehicles differ significantly from traditional airplanes and rotorcraft when it comes to configuration and handling qualities. Handling qualities for traditional airplanes and rotorcraft are often very predictable. All AAM concepts currently under development feature some sort of fly-by-wire flight control system. Regulatory agencies already have decades of experience with certifying fly-by-wire airplanes. Fly-by-wire rotorcraft have proven to be significantly more difficult to certify and several flight test accidents have occurred as a result of handling qualities deficiencies, or “cliffs”. To ensure the safe and timely certification of AAM vehicles, methods to predict these handling qualities cliffs with reduced risk for test pilots is necessary. This thesis focuses on the development of two such methodologies. The first methodology is fully automated and predicts the forces and moments required for a vehicle to perform a given task, which are then compared with the envelopes of attainable forces and moments as a function of the vehicle’s state. While this methodology can predict when an aircraft would run out of control authority during a task, it’s capability to predict a wider range of handling qualities cliffs due to factors such as dynamic instability and pilot-in-the-loop effects is very limited. The second methodology displays the aircraft’s flight envelope in real time to the pilot as a function of the aircraft’s state and displays the location of the aircraft with respect to the boundaries of the envelope. This could alert pilots to any upcoming handling qualities cliffs and help prevent loss of control accidents during flight testing.
"],"dc:identifier":["https://commons.erau.edu/edt/812"],"dc:subject":["Advanced Air Mobility","Urban Air Mobility","AAM","UAM","eVTOL","Certification","Handling Qualities","Flight Envelope","Flight Test","Flight Controls","Aeronautical Vehicles","Navigation, Guidance, Control and Dynamics"],"dc:title":["Prediction of Handling Qualities Deficiencies for Advanced Air Mobility Aircraft"],"thesis:degree_discipline":["Aerospace Engineering"],"thesis:degree_level":["Thesis - Open Access"],"thesis:degree_name":["Master of Science in Aerospace Engineering"]},"updated_at":"2026-07-27T19:26:16Z"}