Toward Certification of Wing-Structure- Integrated Hydrogen Tanks: A Cross-Industry Review of Relevant Standards

Standards are not only crucial for obtaining certification for practical use but also provide essential guidance on what to simulate and how to conduct experimental tests. This study examines the potential applicability of existing standards from various domains, including aerospace and automotive, to Wing-Structure-Integrated high-pressure Hydrogen Tanks (SWITHs). It highlights the associated challenges and uncertainties, acknowledging the absence of a single, all-encompassing standard for SWITHs. We conduct a thorough investigation to identify the most suitable existing standards that could serve as viable alternatives to a dedicated SWITH standard. Our analysis scrutinizes existing standards that could facilitate SWITH certification, with particular emphasis on accommodating externally loaded hydrogen tanks. Assessment criteria are established to determine the standards that best meet the needs of SWITHs, through which we pinpoint four key standards as the most promising alternatives. Moreover, we delineate the technical constraints involved in selecting the maximum nominal working pressure for high-pressure tanks intended for burst tests. Our findings reveal a current upper limit of 525 bar, imposed by the limitations of existing test facilities. The study underscores that
these standards should serve as flexible guiding frameworks rather than rigid protocols, thereby encouraging progressive development in the field of SWITHs.