RECENT ADVANCES IN AEROSPACE PROPULSION SYSTEMS: A REVIEW OF EFFICIENCY, SUSTAINABILITY, AND EMERGING TECHNOLOGIES

Abstract

This review examines recent advances in aerospace propulsion systems with a focus on three interrelated dimensions: efficiency improvement, sustainability, and emerging technologies. The article aims to synthesise current developments in conventional and advanced propulsion concepts across both aviation and space applications. The review adopts a thematic and analytical approach. It surveys major propulsion categories, including air-breathing, rocket, electric, hybrid-electric, hydrogen-based, and advanced space propulsion systems. The discussion is organised around propulsion fundamentals, efficiency-oriented innovations, sustainable propulsion pathways, emerging technologies, key technical and regulatory challenges, and future research directions. The review shows that aerospace propulsion is evolving from a performance-centred discipline toward a more integrated framework that combines thermodynamic efficiency, environmental responsibility, and digital intelligence. Conventional systems continue to improve through advances in engine design, lightweight materials, thermal management, and predictive maintenance. At the same time, sustainable aviation fuels, hydrogen, electric, and hybrid-electric propulsion are gaining strategic importance for low-emission aviation. Emerging technologies such as hypersonic propulsion, detonation-based engines, ion and plasma propulsion, and nuclear-based space propulsion are expanding the future scope of aerospace missions. However, major barriers remain in energy storage, thermal control, infrastructure readiness, safety, and certification. The article offers an integrated review of propulsion developments across aviation and space, highlighting how efficiency, sustainability, and technological innovation are converging to shape the next generation of aerospace propulsion systems.