Environmental and Cost Analysis of Supersonic Cargo Transport: A Comparative Study with Subsonic Aircraft and Other Freight Modes

Rapid-delivery logistics is reviving interest in supersonic cargo aircraft, yet their environmental and economic viability against subsonic and surface freight remains uncertain. This screening-level assessment combines a fuel-based emissions model, a Breguet supersonic performance grid, and a direct operating cost (DOC) decomposition with Monte Carlo uncertainty propagation, for a 1-ton payload over 500,1500, and 5000 km. Relative to the 1500 km subsonic benchmark, a conservative first-generation supersonic case yields 2.30× the CO2 intensity and 2.21× the DOC, while the Monte Carlo median is 1.50× the subsonic CO2 intensity (0.82 kg/ton-km). Across the deterministic parameter grid the CO2 intensity spans 0.52–1.44 kg/ton-km (0.96–2.64× subsonic), with a narrower Monte Carlo 90% interval of 0.67–1.02 kg/ton-km (1.23–1.87×). The DOC is about $2.08/ton-km for a fully filled 1-ton functional unit—upper-leaning, as whole-aircraft crew and fees and the small-payload capital and maintenance rates fall on the costed ton; once load factor (0.5–0.85; filled fraction, not capacity utilization) and fuel-price variability are propagated, the Monte Carlo cost per delivered ton-km spans $2.5–3.5/ton-km (90% interval). Supersonic cargo thus remains a niche, high-value-of-time option: substantial propulsion and aerodynamic gains, with climate accounting expanded to effective radiative forcing (ERF/CO2e), are needed before competitive, sustainable deployment becomes plausible.