Future Propulsion Systems and Energy Sources in Sustainable Aviation

6Pathways to Sustainable Aviation

6.1 Introduction

The outlook for sustainable aviation is bright. Every single sector within aviation industry, from airframe and propulsion companies to avionics (guidance, navigation, and control) and air traffic management (ATM) and operations, are all actively engaged and investing in promising research in greener aviation. Add to these efforts government agencies in the United States and Europe such as National Aeronautics and Space Administration (NASA) and Advisory Council for Aeronautics Research in Europe (ACARE), among others, as well as academia that conduct pioneering research in environmentally friendly transportation. The specific technologies in this sector, from alternative jet fuels to superconducting electric motors/generators and cryo‐cooling thermal management system in hybrid and all electric propulsion aircraft, have reached different technology readiness levels (TRLs) and thus are candidates for new challenges toward certification. In this chapter, we briefly address the specific pathways to sustainable aviation in key technologies, including the challenges in regulations and certifications, public confidence, and societal acceptance.

6.2 Pathways to Certification

Greener aviation, as we discussed in Chapters 3–5, is more than just electric propulsion. However, with the rise of drones in the twenty‐first century (with 940 000 registered unmanned aerial vehicle (UAV) operators in the United States in 2017), a transformational ...