NOT MEASUREMENT SENSITIVE National Aeronautics and NASA-HDBK-7005 Space Administration MARCH 13, 2001 DYNAMIC ENVIRONMENTAL CRITERIA NASA TECHNICAL HANDBOOK NASA-HDBK-7005 March 13, 2001 FOREWORD This handbook is approved for use by NASA Headquarters and all field centers and is intended to provide a common framework for consistent practices across NASA programs. A concerted effort is underway within the NASA engineering community, under the cognizance of the NASA Office of the Chief Engineer, to promote more consistent practices across the NASA centers in the areas of dynamics and structures design and test criteria for spacecraft and payloads. This effort has resulted in NASA standards in the fields of structural design and test factors of safety, loads analyses, vibroacoustic test criteria, and pyroshock test criteria. A parallel effort, also funded by the Office of the Chief Engineer, was undertaken by the Jet Propulsion Laboratory and its contractors to summarize and assess mission dynamic environments, state-of-the-art procedures for predicting the dynamic excitations or loads induced by those environments and the structural responses to those excitations, and for establishing dynamics criteria with appropriate margins for the design and testing of a spacecraft and its components, along with the equipment and procedures used for testing. Contributions were made to this handbook by many members of the aerospace dynamics community; those contributions are gratefully acknowledged. Requests for information, corrections, or additions to this handbook should be directed to the Mechanical Systems Engineering and Research Division, Section 352, Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109. Requests for general information concerning technical standards should be sent to the NASA Technical Standards Program Office, ED41, MSFC, AL, 35812 (telephone 256-544-2448). This and other NASA standards may be viewed and downloaded, free-of-charge, from our NASA Standards Homepage: http://standards.nasa.gov (Original Signed By) W. Brian Keegan Chief Engineer i NASA-HDBK-7005 March 13, 2001 AUTHORS Harry Himelblau Jerome E. Manning Dennis L. Kern Cambridge Collaborative, Inc. Jet Propulsion Laboratory 689 Concord Avenue California Institute of Technology Cambridge, MA 02138-1002 4800 Oak Grove Drive Pasadena, CA 91109-8099 Allan G. Piersol Sheldon Rubin Piersol Engineering Company Rubin Engineering Company 23021 Brenford Street 3531 Alana Drive Woodland Hills, CA 01364-4830 Sherman Oaks, CA 91403-4708 ii NASA-HDBK-7005 March 13, 2001 TABLE OF CONTENTS PARAGRAPH PAGE FOREWORD ................................................................................................................... i AUTHORS ................................................................................................................... ii TABLE OF CONTENTS .................................................................................................... iii LIST OF FIGURES .......................................................................................................... ix LIST OF TABLES .......................................................................................................... xi LIST OF SYMBOLS .......................................................................................................... xiii LIST OF ABBREVIATIONS ............................................................................................... xv 1. INTRODUCTION ................................................................................................ 1 1.1 Purpose...................................................................................................... 1 1.2 Handbook Organization.............................................................................. 2 1.3 References................................................................................................. 3 2. DEFINITIONS..................................................................................................... 5 2.1 Types of Dynamic Environments................................................................ 5 2.1.1 Deterministic Dynamic Environments ................................................ 5 2.1.2 Random Dynamic Environments ....................................................... 6 2.2 Descriptions of Dynamic Environments ...................................................... 8 2.2.1 Time Histories ................................................................................... 9 2.2.2 Average Values................................................................................. 9 2.2.3 Line Spectra ...................................................................................... 10 2.2.4 Autospectra ....................................................................................... 10 2.2.5 Wave-Number Spectra ...................................................................... 11 2.2.6 1/3 Octave Band Spectra................................................................... 11 2.2.7 Maximax Spectra............................................................................... 12 2.2.8 Fourier Spectra.................................................................................. 12 2.2.9 Energy Spectra.................................................................................. 12 2.2.10 Shock Response Spectra .................................................................. 13 2.2.11 Cross-Spectra and Coherence Functions.......................................... 14 2.2.12 Frequency Response and Impulse Response Functions ................... 15 2.3 Hardware Level of Assembly...................................................................... 16 2.4 References................................................................................................. 16 3. DYNAMIC ENVIRONMENTS AND MISSION EVENTS ...................................... 17 3.1 Transportation............................................................................................ 17 3.2 Seismic Events During Pre-Launch ........................................................... 17 3.3 Wind and Turbulence ................................................................................. 18 3.4 Rocket Motor Ignition Overpressure........................................................... 19 3.5 Liftoff Release Loads.................................................................................. 20 3.6 Engine/Motor Generated Acoustic Loads ................................................... 20 3.7 Engine/Motor Generated Structureborne Vibration Loads .......................... 22 3.8 Aerodynamic Sources During Ascent and Entry......................................... 22 iii NASA-HDBK-7005 March 13, 2001 TABLE OF CONTENTS (CONT”D) PARAGRAPH PAGE 3.9 Engine/Motor Thrust Transients ................................................................. 23 3.10 Maneuvering Loads.................................................................................... 23 3.11 Pogo .......................................................................................................... 24 3.12 Solid Motor Pressure Oscillations............................................................... 24 3.13 Liquid Sloshing in Tanks ............................................................................ 24 3.14 Stage and Fairing Separation Loads .......................................................... 25 3.15 Pyrotechnic Induced Loads ........................................................................ 25 3.16 Flight Operations........................................................................................ 27 3.17 Onboard Equipment Operations................................................................. 28 3.18 Planetary Descent, Entry, and Landing ...................................................... 28 3.19 Surface Penetration.................................................................................... 29 3.20 Meteoroid Impacts...................................................................................... 30 3.21 Summary of Environments ......................................................................... 30 3.22 References................................................................................................. 32 4. PREDICTION OF DYNAMIC EXCITATIONS...................................................... 37 4.1 Low Frequency Transient Excitations......................................................... 37 4.1.1 Analytical Models .............................................................................. 37 4.1.1.1 Launch Vehicle Liftoff Excitations ...................................................... 38 4.1.1.2 Payload Liftoff Excitations.................................................................. 39 4.1.2 Extrapolation Techniques .................................................................. 39 4.1.3 Direct Measurements ........................................................................ 40 4.1.4 Assessments..................................................................................... 40 4.2 Low Frequency Random Excitations .......................................................... 40 4.2.1 Analytical Models .............................................................................. 41 4.2.2 Scale Models..................................................................................... 41 4.2.3 Extrapolation Techniques .................................................................