SR-1 Freedom Thermal Architecture Challenges

Scott Thomas; Jared Berg

NASA NTRS · 20260007985

SR-1 Freedom Thermal Architecture Challenges

Abstract

The SR-1 Freedom mission aims to demonstrate nuclear electric propulsion (NEP) and deliver the Skyfall helicopter payload to Mars. Repurposing the existing Gateway Power and Propulsion Element (PPE) spacecraft and combining it with a 20 kWe-class nuclear power module (NPM) presents a variety of thermal architecture challenges. These include unprecedented waste heat rejection requirements, integration with a spacecraft bus originally designed for a different mission profile, and novel packaging constraints. This presentation will describe the simplified concept of operations as it relates to on-orbit thermal environments, early-phase architecture trades and supporting analyses, and planned forward work. We will also discuss our strategy for integrated thermal modeling of the complete spacecraft and examples of interface challenges necessitated by this ambitious effort.

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Thermal SR-1 Freedom Nuclear Electric Propulsion Thermal Modeling

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Scott Thomas, Jared Berg. SR-1 Freedom Thermal Architecture Challenges. https://ntrs.nasa.gov/citations/20260007985

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