ASTM F 3547:2024

1.1 This specification defines the requirements for fuel cells and fuel cell based power systems, including hydrogen-based fuel storage and refueling systems used in electric small Unmanned Aircraft Systems (sUAS). While many requirements specified by this document may apply to larger Unmanned Aircraft Systems (UAS) and manned aircraft, safe operation of these aircraft require additional requirements outside the scope of this document. Fuel cell systems for use in sUAS may be used in both ground operations and in aircraft. Fuel cells used in ground operations are outside the scope of this specification. 1.2 This specification does not define requirements for the systems in which aircraft fuel cells may be utilized, but may require additional functionality in those systems to support fuel cell operations. 1.3 The entity declaring conformance to this specification will typically be the integrator of the fuel cell into the UAS, as many requirements apply to not only the fuel cell itself, but how it interacts with the UAS and with the operator. 1.4 The values stated in SI units are to be regarded as standard. In some cases, non-SI units are used for clarity. 1.5 The regulations of the Civil Aviation Authorities (CAA) remain applicable. 1.6 This 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. 1.7 This 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.

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