1.1 Defence’s regulations for Uncrewed Aircraft Systems (UAS), prescribed within DASR UAS, include three categories of UAS. Only two of these categories relate to the content within Section 4, namely:
Certified: Intended for UAS operations where the UAS Operator expects to operate in all classes of airspace for which it is equipped, and over populous areas.
Specific: Intended for UAS operations where the UAS is not certified to robust airworthiness standards. Consequently, increased operational limitations and use of risk controls provide for safe UAS operation.
1.2 As stated in Section 1 Chapter 1, the DASDRM prescribes design requirements for aircraft systems and functions that are necessary to achieve safe flight in Defence’s proposed configuration, role and operating environment. This sets the scene for Sections 2 and 3 which prescribe additional design requirements particularly aimed at crewed aircraft. However, the UAS context can be somewhat different to crewed aircraft and must be accounted for before these requirements can be applied. The UAS context differences fall into two broad categories:
Absence of on-board crew. Crewed aircraft design requirements may contain inherent assumptions that are not valid or appropriate for UAS. For example, Section 2 Chapter 7 Fire Protection includes visual monitoring and smell as legitimate indirect means for fire detection onboard an aircraft. The assumption here is that a crew is onboard the aircraft and will perform certain actions.
Shifted safety focus. Crewed aircraft design requirements prescribed in Sections 1 – 3 are predominantly focused on ‘safe flight’ from the perspective of keeping the aircraft occupants alive, be they crew or passengers. Presently, UAS do not carry passengers or crew therefore ‘safe flight’ from the perspective of UAS occupants can be discounted. Rather, UAS ‘safe flight’ occurs when the risk to other airspace users, people on the ground, and critical infrastructure are suitably minimised.
1.3 With the above UAS context in mind, Section 4 presents design requirements for UAS by tailoring requirements in Sections 1-3, or prescribing bespoke UAS design requirements.
1.4 Nomenclature. UAS nomenclature varies widely between standards bodies, UAS associations, Aviation Authorities, and even within Defence itself. This chapter employs the UAS nomenclature from ICAO Doc 10019, Manual on Remotely Piloted Aircraft Systems (RPAS), since this will promote nomenclature compatibility with major international Aviation Authorities.
1.5 Chapter 2 presents recognised Airworthiness Codes and design requirements for Certified category UAS. Chapter 3 presents criteria for determining the robustness of technical risk controls that can be applied to Specific category UAS.
1.6 Open category UAS, which must operate within Standard Operating Conditions, are not discussed in this manual on the basis of the Authority’s assumption that these UAS have no design integrity. Therefore, the safety of Open category UAS operations is reliant primarily on operational risk controls.