<p>As the aviation industry continues to grow, the development and introduction of new, environmentally friendly aircraft technologies has been one of the emission-reduction goals established by aviation industry stakeholders. As such, newer aircraft and engine concepts have been developed. One of these concepts is the More- Electric Propulsion (MEP) engine system. Relevant metrics are necessary to assist aviation stakeholders in measuring the sustainability impact of MEP technologies. This study proposes a multi-criteria sustainability assessment of MEP technologies using a life cycle sustainability assessment (LCSA) framework. After providing a relevant literature review on the more-electric propulsion and the sustainability frameworks currently used in the aviation industry, a comprehensive review methodology is employed to identify key parameters that will address the economic, social, and environmental aspects of operating an aircraft. The definition of and relevant metrics to measure sustainability are discussed along with a detailed explanation of the proposed novel framework and how to use it. Through a comparative case study of two aircraft, the findings suggest that more-electric propulsion systems can contribute to sustainable development by positively influencing economic, social, and environmental outcomes. Although the acquisition cost of newer aircraft is relatively high, operators may still achieve economic profitability while simultaneously advancing social and environmental objectives. Finally, this article provides guiding information for policymakers and potential investors, emphasizing that while the economics of evaluating aircraft are crucial, social and environmental aspects are also important.</p>