NATO AEP-4671 PDF

Whilst military aircraft are not specifically required to comply with civil airworthiness regulations as agreed in the ICAO¹ Convention on International Civil Aviation (Article 3), it is the intention of this document to correspond as closely as practicable to a comparable minimum level of airworthiness for fixed-wing aircraft as embodied in documents such as EASA² CS-23 (from which USAR is derived) and 14 CFR³ Title 14 Part 23 whilst recognizing from military experiences that there are certain unique features of UAS that require modification to those civil airworthiness requirements and/or the addition of new individual requirements or new subparts. Civil codes were utilized as the foundation for USAR because they represent the minimum airworthiness requirements for flight in non-segregated airspace with minimal or no restrictions. Additionally, many military fixed-wing UAS have flight profiles similar to that of General Aviation, making the selection of civil airworthiness codes a practical starting point.

In line with the JAA-Eurocontrol Taskforce recommendations, the following areas are not covered by this airworthiness code:

• Control station security,

• Security of the command and control data link from wilful interference,

• Airspace integration and segregation of aircraft (including “sense and avoid”),

• The competence, training and licensing of UAS crew, maintenance and other staff,

• Approval of operating, maintenance and design organizations,

• The type of operation,

• Vehicle Management and Navigation requirements,

• Frequency spectrum allocation,

• Noise, emission, and other environmental certification,

• Launch/landing equipment that is not safety critical and which does not form part of the Type Certification Basis,

• Operation of the payload (other than its potential to hazard the aircraft),

• Carriage and release of weapons, pyrotechnics and other functioning or non-functioning stores designed for release during normal operations,

• Non-deterministic flight, in the sense that UAS flight profiles are not pre-determined or UAS actions are not predictable to the UAS crew,

• Sea-basing,

• Piloting from an external or internal control box,

• Supersonic flight.

It is expected that these areas will be subject to other forms of approval by Certifying Authority in order to ensure a total aviation safety approach. Where such approval requires technical assessment, the Certifying Authority may supplement these requirements with suitable additional conditions as appropriate.

It is recognized that ‘sense and avoid’ is a key enabling issue for UAS operations. The derivation and definition of ‘sense and avoid’ requirements is primarily an operational issue and hence outside the scope of USAR. However, once these requirements have been clarified, any system designed and installed to achieve these objectives is an item of installed equipment within a UAS and hence falls under the airworthiness requirements of USAR.

¹ International Civil Aviation Organization

² European Aviation Safety Agency

³ Code of Federal Regulations