Jaylon Uzodinma

(Advisor: Prof. Dimitri Mavris]
will defend a doctoral thesis entitled

A Probabilistic, Life Cycle-Based Approach for Technology Assessment of Hybrid-Electric Propulsion in Single-Aisle Aircraft

On
Friday, August 8th at 2:00 p.m.
Collaborative Visualization Environment (CoVE)
Weber Space Science and Technology Building (SST II)
and
Microsoft Teams
Abstract
The aviation industry is at a pivotal juncture, facing the dual challenges of meeting rising global travel demand while significantly reducing its environmental footprint. Single-aisle aircraft currently account for more than half of annual climate-impacting aviation emissions and are projected to comprise over 75% of all aircraft deliveries between 2024 and 2042. In response, the industry is exploring advanced technology development for the next generation of single-aisle aircraft. One technology of interest is hybrid-electric propulsion, and there are two key challenges to the successful development and deployment of a next-generation single-aisle aircraft powered by hybrid-electric propulsion. 
The first challenge is that hybrid-electric propulsion systems are emergent and rely on rapidly developing technologies for feasibility and viability. Thus, technological uncertainty associated with components of the hybrid-electric powertrain affects the design and performance of the overall aircraft. Current technology assessment approaches often disregard technological uncertainty, affecting vehicle design and quantified environmental performance. This dissertation addresses this research gap by quantifying how technological uncertainty impacts optimal design parameters and by comparing uncertainty management methods. 
The second challenge is that aircraft powered by hybrid-electric propulsion may have unintended environmental impacts through life cycle effects. Current technology assessment approaches focus on reducing fuel use enabled by hybrid-electric propulsion systems. However, electricity generation to supply the electrical energy storage systems of the hybrid-electric powertrain has its own environmental impacts, which should also be accounted for during analysis. Additionally, battery charging is not a perfectly efficient process, and batteries have operational life limits shorter than those of aircraft. Thus, the operational performance of batteries has environmental impacts that are also ignored by traditional technology assessment approaches. 
This dissertation explores the benefits of the combined use of design under uncertainty approaches and life cycle assessment for technology assessment of single-aisle aircraft powered by hybrid-electric propulsion. A life cycle assessment module was developed and integrated with a hybrid-electric vehicle performance model to assess the value of the combined approach. Studies were executed in three research areas: vehicle design under uncertainty, life cycle-based evaluation, and life cycle-based design under uncertainty. Results from the three research areas were shown to support the overarching research hypothesis, which stated that the combined use of uncertainty-informed design and life cycle assessment during technology assessment yields hybrid-electric aircraft design solutions that are significantly different—in both design parameters and environmental impact estimates—from those derived using a vehicle-level, deterministic approach. Furthermore, the integrated method provides more holistic insights for technology assessment and decision-making.

Committee
•    Prof. Dimitri Mavris – School of Aerospace Engineering (advisor)
•    Prof. Graeme Kennedy – School of Aerospace Engineering
•    Prof. Daniel Schrage – School of Aerospace Engineering
•    Dr. Raphael Gautier – School of Aerospace Engineering
•    Dr. Dominic Barone – The Boeing Company