In order to meet the objectives of the European Green Deal by 2050 in the aviation sector, the transition towards H2-powered aviation is the solution with the most potential. Although hydrogen-powered aircrafts exist, the current cost of storing and using H2 as a fuel in prolonged flights make their democratization impossible. The main blocking point is the absence of viable storage systems of H2 in aircrafts considering the strict limitations in terms of weight, volume, and cost-efficiency. A sensitivity analysis shows how the economics depend on the tank’s gravimetric index (GI). Today’s technology can barely achieve 20% GI for 500kg of H2, while industry actors need at the very least 35% GI for 500kg of H2 to transition towards H2-powered aviation. OVERLEAF intends to develop a game changer Liquid Hydrogen (LH2) storage tank to enable the transition towards H2-powered aviation. Based on a disruptive design (under patent process) and leveraging innovative materials and technologies, the OVERLEAF solution is expected to boast a GI higher than 60% for 500kg of LH2, with no venting over 24h. Furthermore, the concept is an enabler for using the aircraft’s fuselage as the outer tank, allowing to seamlessly integrate the tank in the aircrafts structure. OVERLEAF will have an interdisciplinary R&D approach focusing on advance materials engineering, testing and combination at lab and at pilot scale, together with appropriate simulation of different design architectures of the hydrogen storage system. The project will be based on three distinctive phases and implemented in 7 Work Packages. The consortium includes multidisciplinary partners from 6 different EU countries and contains all the necessary expertise and know-how to carry-out all tasks needed to achieve OVERLEAF’s ambitious objective.