MS Thesis Proposal
Marco Serapiglia
(Faculty advisor: Professor Dimitri Mavris)
"Reentry Logistics: a Methodology for the Design of High-Cadence LEO-to-Earth Supply Chains"
Friday, July 31
12:00 - 2:00 p.m.
Weber, CoVE
Abstract:
The reduction of launch costs has driven a rapid expansion of commercial activity in Low Earth Orbit (LEO), yet the return leg of this exchange has received comparatively little attention. Applications ranging from in-space manufacturing to the recovery of reusable satellites and cargo return from commercial space stations converge on a common need: bringing mass down from orbit safely, frequently, and efficiently. Operators are already committing to weekly or monthly returns, yet propose widely different vehicle architectures, suggesting that the tradeoffs between vehicle design and logistics costs have yet to be quantified. Scaling reentry from a sporadic event to recurring traffic is thus an operational challenge, rather than a technological one, and it exposes a largely unexplored high-cadence LEO-to-Earth supply chain.
What distinguishes this supply chain from conventional logistics problems is the atmospheric entry, descent, and landing (EDL) segment. The physics of reentry, together with the regulatory regime built around it, determines which vehicles can reach which sites, whether payloads can withstand a given trajectory, and at what cost. For high-cadence operations, this cost extends beyond propellant: it includes licensing, disruption to third-parties, and waiting time for landing opportunities, which open periodically. To date, no framework couples EDL trajectory analysis with fleet-level logistics and landing-site investment decisions: this thesis addresses that gap.
The problem is posed for a single operator returning a growing and heterogeneous volume of payloads from LEO to customers around the globe. It is formulated as a centralized, profit-maximizing mixed-integer linear program (MILP) that jointly determines three coupled decisions: the fleet of reusable vehicles; the portfolio of qualified landing and refurbishment sites; and the selection and routing of missions through the supply chain. A vehicle-level layer simulates EDL trajectories to precompute the feasibility and cost of each option; an operator-level layer then optimizes the portfolio over a multi-period horizon, capturing congestion at finite-capacity sites through a queueing-based waiting time.
Through parametric experiments, the thesis characterizes how this portfolio evolves as demand grows and diversifies: when operations shift from a single landing site to multiple sites, which vehicle families the fleet converges to, what disruption is imposed on third parties, and whether different operator priorities produce structurally distinct designs. As the first formal study of this problem, the thesis both informs the operators and regulators of this emerging market and opens research directions beyond its scope, from the concurrent design of vehicle and supply chain to reentry scheduling and competition among operators.
Committee:
Dr. Dimitri Mavris (advisor), School of Aerospace Engineering
Dr. Koki Ho, School of Aerospace Engineering
Dr. Tristan Sarton du Jonchay, School of Aerospace Engineering