Hydrogen fuel cells are intensively discussed as part of the power train in new, sustainable, all-electric aircraft designs. Especially the Low Temperature Polymer Electrolyte Fuel Cell (LT-PEMFC) offers potential for zero-emission propulsion in aviation, due to its comparably high technological readiness level, power density and efficiency. However, several challenges for LT-PEMFC commercialization in aviation remain. Among these, the high cooling system drag associated with conventional LT-PEMFC cooling system and limitations of reactant flow through the Gas Diffusion Layer (GDL) have been identified. Within the scope of the EU Horizon Project “Environmental Aviation for All Classes of Aircraft” (EFACA) new fuel cell technologies are developed. Most notably, we demonstrate a novel “Phase change plus heat pump” (PCHP) cooling concept for reducing the heat exchanger surface to the ambient air, required for fuel cell heat dissipation. Furthermore, a new GDL design is conceived and numerically characterized for its suitability in high-load, aviation environments. In this work we present latest results – experimentally and numerically - on PCHP cooling and our new GDL design and discuss their projected potential for advancing LT-PEMFC suitability for aviation.