Projection of Key Powertrain Component Figures of Merit for Overall Assessment of Electric Flight Scenarios

Abstract

One potential pathway for the future of aviation is the electrification of the propulsion system. This study connects projections for component technology development with powertrain range predictions for electric aircraft. The investigation involves summarising electrified propulsion topologies, identifying key components, and projecting the advancements of individual technologies with respect to relevant key metrics such as specific power and efficiency. These component projections are then applied to an overall assessment of all-/hybrid-electric powertrains for various aircraft classes. The paper highlights the increasing potential of electrified propulsion from 2025 to 2070 under different development scenarios - a conservative and a progressive scenario. Both emphasise the impact of the thermal management system (TMS) on powertrain development. In particular, the pertinence of considering the TMS in the preliminary design of electrified aircraft with a high degree of accuracy is derived. The assessment identifies key contributors, such as fuel cells and TMS. An improvement of their respective specific power and specific heat rejection significantly impact the predicted aircraft ranges - particularly in current and near-term technology levels. Negligence with regards to TMS effects in preliminary design may lead to an overly optimistic prediction of achievable aircraft range.