event image

Launch Vehicle and Spacecraft Structural Dynamics

Abstract: During launch and ascent a launch vehicle and its payload will experience severe structural loading. These loads set the primary design requirements for most of the launch vehicle and spacecraft structure. Critical load producing events include liftoff, atmospheric flight, which includes turbulence/gust, buffet, and static-aeroelastic contributors, jettison and separation events, and engine ignitions and shutdowns. Predicting loads for these various events requires complex models, analyses, tests, and involve numerous organizations. Complicating matters is the fact that the fully integrated launch vehicle/spacecraft system needs to be addressed, but the integrated system cannot be tested. The seminar will provide an overview of critical aspects of predicting liftoff and ascent loads, including model development and analysis methodologies. The multi-disciplinary nature of the processes will be described and some interesting examples will be provided, including a discussion o! f statistical computation of loads with small sample sizes and how the laws of physics makes it possible to invert singular stiffness matrices.

Bio: Dr. Kabe is the Principal Director of the Structural Mechanics Subdivision at The Aerospace Corporation. The Subdivision is responsible for developing specifications and standards for the design and qualification of launch vehicles and spacecraft; these standards include: Independent Structural Loads Analyses; Test Requirements for Launch, Upper-Stage, and Space Vehicles; Space Systems - Structures, Structural Components, and Structural Assemblies; Moving Mechanical Assemblies for Space and Launch Vehicles; Criteria for Explosive Systems and Devices on Space and Launch Vehicles; and Mass Properties Control for Space Systems. The latter six became the current AIAA standards. The Subdivision is also responsible for independent launch vehicle and spacecraft model development, independent loads analyses, independent structural integrity assessments, and independent day-of-launch loads placard analysis. Dr. Kabe previously served as Director of the Structural Dynamics Department ! at The Aerospace Corporation. He has made many notable contributions to the state of the art of launch vehicle and spacecraft Structural Dynamics, including the development of the time domain buffet loads analysis approach, the concept of extracting turbulent wind features from measured winds for gust response analysis, and the separation of slowly and rapidly changing wind features for day-of-launch placard analysis. His developments are used today to compute loads for the Air Force's Atlas V and Delta IV launch vehicles, and NASA's new Space Launch System launch vehicle. Dr. Kabe has published numerous papers, and is an Associate Fellow of the AIAA. Dr. Kabe has led review teams that have assessed the readiness for flight of systems such as the Titan IV and the Shuttle Radar Topography Mission, and the viability of proposals such as the Mars Sample Return Mission. Dr. Kabe also served on the Defense Science Board Aviation Safety Fask Force. Dr. Kabe has received numerous! commendations and awards, including the Aerospace President’s! Achieve ment Award, and the Aerospace Trustees’ Distinguished Achievement Award. His B.S., M.S., and Ph.D. degrees are from UCLA.