In response to the climate crisis, the aviation industry pledged through ICAO to become climate neutral by 2050. One of the most promising solutions to achieve this goal is the introduction of hydrogen-fueled aircraft. Using hydrogen as fuel on an aircraft presents however huge challenges, especially due to its complex storage, as it must be stored in pressurized cryogenic tank. This study focuses on the integration of a medium-fidelity cryogenic hydrogen tank model into an overall aircraft design tool (FAST-OAD) and its exploitation to optimize a hydrogen aircraft. This integration allows the comparison of different tank configurations at the aircraft level and the search of the optimum ones, depending on the high-level requirements or optimization criteria.