Aviation will be under increasing pressure to reduce its impact on global warming as other sectors transition rapidly to more sustainable options. Due to long lead times in development and certification, new airplanes delivered in the next decade will be similar to current models and have no significant impact on reducing aviation's global warming contribution. Future aviation will become hampered by more regulatory restrictions and ever-increasing taxes/fees, unless novel technologies are developed to achieve zero emissions on a long-term basis. As part of the development of a hydrogen-based aviation transition plan, we will map out potential novel technologies.