ASTM F3686-24 PDF
1.1This practice provides unmanned aircraft systems (UAS) manufacturers with the requirements toward civil aviation authority (CAA) production approval that may be associated with a CAA airworthiness approval for UAS without people on board.
1.2The Type Certification and Production Certificate (TC/PC) approval process is well-entrenched within the aviation industry. Internationally, these processes have good harmonization from country to country however those processes can be different depending on the country”s aviation history, governmental organization, size of industry, safety culture, etc. The TC/PC process results in a highly robust product that has undergone compliance to the rigor that aviation regulations require. The TC/PC process is synonymous with the safety record of traditional manned aviation and the public will expect similar safety from the UAS industry.
1.2.1ICAO State letter AN 11/61-22/70, dated 23 August 2022 proposed a new Annex 6-Operation of Aircraft, Part IV-International Operations-Remotely Piloted Aircraft Systems (UAS). The Standards and Recommended Practices (SARPs) in Annex 6, Part IV are applicable to the operation of RPAS certificated in accordance with Annex 8-Airworthiness of Aircraft (TC). The ICAO State letter and the foreword to Annex 6, Part IV identifies three categories of unmanned aircraft systems operations: Open, Specific and Certified. These three categories are summarized below:
1.2.1.1The Open category poses the lowest operational risk. No authorization to operate from the CAA is required if operations are conducted within defined limitations such as VLOS only, specified distances from aerodromes, proximity of persons, maximum altitude, etc. The production of the UAS associated with Open category operations are typically not overseen by CAAs.
1.2.1.2The Specific category addresses the medium operational risk. Within the Specific category, operational authorization is required from the governing CAA who may impose restrictions or limitations based on the type of operation, the complexity of the UAS and the qualifications and experience of operating personnel. Operational approvals are based on analysis of a safety risk assessment and application of mitigation means to reduce risks to an acceptable level. Of significance to the Specific category is that the mitigated risk level is below that which warrants the full application of manned aviation principles, for example, below the TC/PC process. One methodology used to analyze safety risk is the JARUS Specific (category) Operational Risk Assessment (SORA). The SORA further divides the Specific category into Low, Medium, and High risk.
1.2.1.3The Certified category deals with the highest operational risk. The safety risks within the Certified category have increased to an equivalent level as manned aviation and is typical regulated as such (for example, operator certification, UAS type certification, remote flight crew licensing, etc.).
1.2.2In Fig. 1, the Open, Specific, and Certified categories are identified per the ICAO state letter. Further, the Specific category has been broken into Low, Medium, and High risks per the SORA. The terms “highest” and “lowest” are used to differentiate the Low risk and robustness associated with the Open category and the High risk and robustness associated with the Certified category. This practice addresses the production requirements for UA operating in the ICAO Specific category associated with Low, Medium, and High risk.
FIG. 1Relationship Between Operational Risk and Production Requirements
1.2.3As the categories and associated risks increase in Fig. 1, so does the:
(1)Number of requirements that need to be met for production authorization; (2)Robustness of the requirement outcomes; (3)Rigor required by the applicant to demonstrate compliance to the requirements; (4)Resulting quality of the product being made; and (5)Reliability of the product.
1.2.4The TC/PC process remains the gold standard for safety and the corresponding acceptance of risk within the operation of the product. Note that the tiers proposed by this practice correspond to the Specific category”s three levels of risk (low, medium, and high). There is a sizable difference in the robustness of the requirements and the production rigor (number or details, or both) from Tier 3 to Tier 2. There are fewer differences between Tier 2 and Tier 1. The diagram also shows the minimal differences between Tier 1 and the existing TC/PC process. In other words, Tier 1 has a high degree of commonality with most CAA TC/PC requirements; however, the details of some requirements may vary or have unique domestic adaptations particular to the governing CAA, or both, that may necessitate additional requirements not captured by the scope of this practice.
1.3In this practice, a scalable risk-based assessment similar to the Joint Authorities for Rulemaking of Unmanned Systems Specific Operations Risk Assessment (JARUS SORA) for determining CAA Tiers 1-3-based production approval is used.
1.3.1As an example, the European Union Aviation Safety Agency (EASA) framework incorporating the SORA operational safety objectives (OSO) #2 was used to guide the UAS manufacturer”s level of production robustness based upon integrity and assurance (reference Appendix X1). Tier 1 is the highest production robustness that should enable broad access to operations when combined with airworthiness/type certification. Tier 2 is the medium robustness that should enable UAS manufacturers to lower risk Specific and Open operations. Tier 3 is the lowest robustness limiting UAS manufacturers to more restrictive operations with even lower risk. The assessed operational risk is commensurate with the manufacturer”s production rigor. For example, UAS intended for higher risk operations necessitate greater production rigor, quality standards, and oversight (reference Annex A1).
1.4In this practice, a roadmap is provided for small, medium, and large manufacturers to pursue production approval through a governing CAA. This standard roadmap also allows companies to progress their organization from the initial Tier 3 requirements to advanced Tier 1.
1.5This practice has been purposefully designed within the broader context of the ASTM F38 library. Although the original source materials for the content presented here were intended to function as standalone documents, the ASTM working group has consciously removed any redundant information in favor of adopting a referential “single-source-of-truth” approach. Consequently, when applying this standard, it is essential to consider and integrate all relevant ASTM F38 standards to ensure its comprehensive and accurate implementation.
1.6When intending to utilize the information provided in this practice as a means of compliance for production approval, it is crucial to consult with the respective governing authority (for example, CAA) regarding its acceptable use and application. To find out which authorities have accepted this standard (in whole or in part) as an acceptable means of compliance to their regulatory requirements (hereinafter “the Rules”), please refer to the ASTM F38 webpage (www.ASTM.org/COMMITTEE/F38.htm).
1.7This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.8This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.