With the popularity of unmanned aircraft systems (UAS), there is a growing need to assess airworthiness for safe operations in shared airspace. In the context of this thesis, shared airspace implies the introduction of UAS into airspace designated for manned aircraft. Airworthiness guidelines are generally statements that state safety requirements to prevent unwanted consequences, such as aircraft accidents. Many governmental agencies such as the U.S. Federal Aviation Administration (FAA) analyzed the risks of UAS to third-parties, all personnel and properties exterior to the aircraft. This thesis concerns the adaptation of existing airworthiness documents written for manned aircraft to UAS. The proposed method has three stages that are applied in sequence to identify relevant and irrelevant airworthiness statements, the building blocks of an airworthiness document, with regard to UAS. This method is applied to MIL-HDBK-516C, used as a case study; however, the proposed methodology can be applied to any airworthiness document developed for manned aircraft. This thesis presents a list of all MIL-HDBK-516C airworthiness statements that are directly relevant, indirectly relevant, and irrelevant to UAS; additionally, the indirectly relevant airworthiness statements to UAS are provided along with suggested modification. / M.S. / With the popularity of unmanned aircraft systems (UAS), there is a growing need to assess airworthiness for safe operations in shared airspace. Airspace is the available air for aircraft to fly in; most airspaces are regulated and are subject to the jurisdiction of a particular country. In the context of this thesis, shared airspace implies the introduction of UAS into airspace designated for manned aircraft. Airworthiness guidelines are generally statements that state safety requirements to prevent unwanted consequences, such as aircraft accidents. Many governmental agencies such as the U.S. Federal Aviation Administration (FAA) analyzed the risks of UAS to third-parties, all personnel and properties exterior to the aircraft. This thesis concerns the adaptation of existing airworthiness documents written for manned aircraft to UAS. The proposed method has three stages that are applied in sequence to identify relevant and irrelevant airworthiness statements, the building blocks of an airworthiness document, with regard to UAS. This method is applied to MIL-HDBK-516C, Department of Defense Handbook: Airworthiness Certification Criteria, used as a case study. MIL-HDBK-516C is a military handbook used for airworthiness guidance. However, the proposed methodology can be applied to any airworthiness document developed for manned aircraft. This thesis presents a list of all MIL-HDBK-516C airworthiness statements that are directly relevant, indirectly relevant, and irrelevant to UAS; additionally, the indirectly relevant airworthiness statements to UAS are provided along with suggested modification.