Methodology and Development of SLS Ascent Boost Phase Loads

Lauren Griggs; Jayme Allgood; Scott Swatzell; Thomas Howsman; Austin Decker

NASA NTRS · 20210016682

Methodology and Development of SLS Ascent Boost Phase Loads

Lauren Griggs·Jayme Allgood·Scott Swatzell·Thomas Howsman·Austin Decker

Abstract

The methodologies and development of the loads experienced in the boost phase of ascent flight of the NASA Space Launch System (SLS) Block I vehicle will be presented in this paper. As is common practice, a series of fixed time/mass finite element models of the vehicle were developed for the purpose of evaluating the structural loads and accelerations for particular Mach ranges associated with the boost phase of flight. Load contributors, which vary between Mach bins, include the flight mechanics induced portion of the loads (e.g., Static-Elastic (STEL) or Vehicle Load Indicator (VLI) tool results), gust loads, buffet loads, solid rocket motor thrust oscillations, maneuvering loads, and preplanned test input induced loads. Each of these load contributors will be examined in this paper, as well as the boost phase loads combination equation used to generate the final loads.

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Lauren Griggs, Jayme Allgood, Scott Swatzell, Thomas Howsman, Austin Decker. Methodology and Development of SLS Ascent Boost Phase Loads. https://ntrs.nasa.gov/citations/20210016682

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