Chemical Emissions and Near‑Field Dispersion of Suborbital Carriers in Conceptual Design
Fabrizio BORGNA, Roberta FUSARO, Davide FERRETTO, Sara GNACCARINI, Nicole VIOLA
Abstract. As suborbital flights and space tourism move from promise to practice, quantifying their near-ground emissions is essential for responsible deployment and regulatory assessment. This study develops a reproducible, end-to-end methodology to quantify propulsive emissions and near-field plume dispersion for a suborbital carrier aircraft. The methodology is demonstrated on a representative point-to-point mission from the Italian Taranto–Grottaglie spaceport, transporting Virgin Galactic’s SpaceShipTwo to approximately 15 km prior to release. Objectives are to generate phase-resolved emission source terms and translate them into site-specific ground concentrations to support early design and regulatory assessment. The methodology integrates high-fidelity mission simulations with the analytical BFFM2 emissions-estimation method to compute chemical source terms in an “idle-to-idle” approach, distinguishing fuel-proportional species (CO₂, H₂O, SOx), from power-dependent species (CO, NOₓ, HC, PM). For each Landing and Take-Off (LTO) cycle phase, phase-averaged emission rates are represented as continuous elevated point sources and fed into an analytical Gaussian-plume model to compute spatially resolved concentrations C(x,y,z) of pollutants and greenhouse gases. The methodology is benchmarked against airport dispersion measurements and validated by cross-comparison with high-fidelity pollutant dispersion simulations. The proposed framework provides regulators and designers with a validated, transparent tool for early environmental evaluation of reusable suborbital operations, enabling informed decisions on site selection and operational constraints.
Keywords
Suborbital vehicles, Emission Estimation, Pollutants Dispersion, Local Air Quality, Environmental Impact
Published online 7/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Fabrizio BORGNA, Roberta FUSARO, Davide FERRETTO, Sara GNACCARINI, Nicole VIOLA, Chemical Emissions and Near‑Field Dispersion of Suborbital Carriers in Conceptual Design, Materials Research Proceedings, Vol. 69, pp 1018-1023, 2026
DOI: https://doi.org/10.21741/9781644904251-176
The article was published as article 176 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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