The HyStor project was carried out under the Niedersachsen Aviation Research Programme (NiFö) and funded by the German Ministry of Economic Affairs and Climate Action through the NKBF2017 programme. It brought together Airbus, the German Aerospace Center (DLR), and industrial partners such as InFactory Solutions to develop a cryogenic hydrogen tank for commercial aircraft. Airbus led the overall effort, DLR supplied research expertise in composite structures and process monitoring, while InFactory Solutions contributed sensor technology for structural health monitoring (SHM). The collaboration spanned several years, during which the partners coordinated design, manufacturing, and validation activities and produced a series of scientific publications and patent filings.
Technically, HyStor focused on defining and evaluating critical design features of a double‑walled composite hydrogen tank. The design incorporated a carbon‑fiber reinforced polymer (CFRP) outer shell and a duroplastic inner liner, aiming to reduce structural weight while maintaining integrity under cryogenic temperatures. The project established key design parameters for the tank hull and dome, as well as isolation and integration features that ensure compatibility with aircraft systems. The resulting design demonstrated significant weight savings compared with conventional metallic tanks, improved geometric flexibility, and potential cost reductions in manufacturing.
A core objective was the development of a fibre‑wrapping manufacturing process that could meet the stringent quality requirements of commercial aviation. HyStor advanced tooling, liner, and coating technologies, and introduced a rotational axis lay‑up method to produce thin‑walled, high‑strength structures. The process was validated through a full manufacturing demonstration, confirming that the composite tank could be produced at industrial rates while maintaining the necessary mechanical and thermal performance. The demonstration also integrated sensor placement into the lay‑up, enabling real‑time monitoring of the manufacturing process.
The project also pioneered a cryogenic SHM system tailored to hydrogen tanks. Various SHM techniques—based on Lamb waves, acoustic surface waves, and fibre‑optic or dielectric sensors—were evaluated under extreme temperature swings and changing fill levels. A sensor array of piezo‑composite elements was developed to withstand the operational strains, and a time‑domain reflectometry system from InFactory Solutions was adapted to monitor the infusion front during lay‑up. The SHM system proved capable of detecting and localising damage such as micro‑cracks along sensor lines, providing a foundation for future fault‑tolerant aircraft structures.
Data management and integration were addressed by developing automated workflows that capture sensor data during manufacturing and feed it into aircraft maintenance systems. This approach supports early defect detection and facilitates compliance with regulatory standards. The combined results of design definition, process development, and SHM validation establish a robust platform for the next generation of hydrogen‑powered aircraft, aligning with the broader goal of achieving emission‑free flight.
In summary, HyStor delivered a comprehensive set of technical achievements: a lightweight, structurally sound composite hydrogen tank design; a scalable manufacturing process with integrated monitoring; and a validated SHM system for cryogenic conditions. These outcomes, achieved through close collaboration among Airbus, DLR, and industrial partners, provide a critical step toward the commercial deployment of hydrogen‑powered aircraft and contribute to the environmental sustainability of aviation.