HyPoTraDe aims to design, assemble, and ground-test a set of 500-kW modular fuel cell-battery hybrid-electric DEP powertrain architectures, including cryo-enabled thermal management with ΘΕα > 0.12, emulating operation in a relevant environment (FL > 150). The ground testing campaign will lead to characterization of the optimal system architecture, validation of failure mode mitigations for the groundbreaking powertrain, demonstration of complex operating requirements (e.g., operation at high coolant temperatures, start-up and shut-down characteristics, in-flight restart and battery charging, etc.), and assessment of the fail-safe capabilities of the modular powertrain. Further, the system will be complemented with a digital twin, validated using the results from the ground test campaign. HyPoTrade covers the disruptive maturation and adaptation of fuel cell systems for aeronautical powertrain applications via ground testing of different system architectures with cryo-enabled heat management and representative electric loads, following the demonstrator strategy outlined in the CAJU SRIA.