CEN/TR 17603-32-26:2022

SLOVENSKI STANDARD
01-september-2022
Vesoljska tehnika - Priročnik za analizo mehanskih obremenitev vesoljskih plovil
Space engineering - Spacecraft mechanical loads analysis handbook
Raumfahrttechnik - Handbuch zur Analyse von mechanischen Lasten
Ingénierie spatiale - Manuel d’analyse des charges mécaniques pour vaisseaux spatiaux
Ta slovenski standard je istoveten z: CEN/TR 17603-32-26:2022
ICS:
49.140 Vesoljski sistemi in operacije Space systems and
operations
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL REPORT CEN/TR 17603-32-26

RAPPORT TECHNIQUE
TECHNISCHER BERICHT
June 2022
ICS 49.035; 49.140
English version
Space engineering - Spacecraft mechanical loads analysis
handbook
Ingénierie spatiale - Manuel d'analyse des charges Raumfahrttechnik - Handbuch zur Analyse von
mécaniques pour vaisseaux spatiaux mechanischen Lasten

This Technical Report was approved by CEN on 13 April 2022. It has been drawn up by the Technical Committee CEN/CLC/JTC 5.

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium,
Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.

CEN-CENELEC Management Centre:
Rue de la Science 23, B-1040 Brussels
© 2022 CEN/CENELEC All rights of exploitation in any form and by any means Ref. No. CEN/TR 17603-32-26:2022 E
reserved worldwide for CEN national Members and for
CENELEC Members.
Table of contents
European Foreword . 10
Preface. 11
1 Scope . 13
2 References . 14
3 Terms, definitions and abbreviated terms . 15
3.1 Terms from other documents . 15
3.2 Terms specific to the present document . 16
3.3 Abbreviated terms. 17
4 Overview of the loads analysis process . 21
4.1 Introduction . 21
4.2 Loads cycles . 22
4.3 Logic and sequence of loads analysis . 23
4.4 Loads and verification approach (prototype or protoflight) . 24
4.5 Loads and levels of assembly . 26
4.6 Mechanical loads for design and verification . 27
4.6.1 Spacecraft flight environments and dynamic loads . 27
4.6.2 Vibration environments and frequency range . 27
4.6.3 Introduction to analysis and test types for verifying mechanical
requirements . 28
4.6.4 Static and quasi-static loads . 30
4.6.5 Static loads test . 32
4.6.6 Spacecraft-launcher coupled loads analysis . 33
4.6.7 Sine vibration . 34
4.6.8 Spacecraft design loads and test predictions versus LV/SC CLA
results . 36
4.6.9 Random vibration and vibro-acoustic environment . 37
4.6.10 Shock testing . 39
4.7 Basic principles, criteria and assumptions in structure and loads verification . 40
4.7.1 Introduction . 40
4.7.2 Equivalence criteria for loads and environments . 40
4.7.3 Criteria for assessing verification loads . 42
4.7.4 Main inconsistencies of the loads verification process . 42
4.8 Notching in sine and random vibration testing . 43
4.8.1 Introduction . 43
4.8.2 Example of requirements . 44
4.8.3 Basic principles . 44
4.8.4 Response and force limiting . 45
4.8.5 Criteria for notching justification . 46
4.8.6 Conclusions on notching in sine and random vibration testing . 48
4.9 References . 49
5 Background on structural dynamics . 50
5.1 Introduction . 50
5.1.1 The dynamic environment . 50
5.1.2 Types of structural analysis . 51
5.1.3 List of topics . 51
5.1.4 Principal notations . 52
5.2 Dynamic environments – analysis and specifications . 54
5.2.1 Generalities . 54
5.2.2 Example - the maiden flight of Ariane 1 . 55
5.2.3 Sine environment . 57
5.2.4 Transient environment . 62
5.2.5 Random environment . 65
5.2.6 Sine-equivalent dynamics . 74
5.2.7 Combined environments . 83
5.3 Dynamic analysis . 86
5.3.1 Frequency domain analysis . 86
5.3.2 Modal approach . 88
5.3.3 Effective mass models . 92
5.3.4 Craig-Bampton models . 93
5.4 Coupled analysis and notching in sine tests. 107
5.4.1 FRF coupling . 107
5.4.2 Modal approach . 108
5.4.3 Simple example . 109
5.4.4 Use of the shock response spectrum . 111
5.5 Primary and secondary notching . 115
5.5.1 Modes concerned by primary notching . 115
5.5.2 Secondary notching . 115
5.5.3 Simple example . 116
5.5.4 Conclusions on notching in sine tests . 118
5.6 Random tests . 118
5.6.1 Issues on random tests . 118
5.6.2 Mechanical equivalence example . 119
5.6.3 Notching in random vibration tests . 121
5.7 Practical aspects of modal effective masses . 124
5.8 Conclusions . 126
5.9 References . 126
6 Launcher / spacecraft coupled loads analysis . 129
6.1 Introduction . 129
6.1.1 General aspects . 129
6.1.2 Launch loads and terminology used in the CLA process . 130
6.1.3 The role of the CLA within the loads cycle . 132
6.2 The phases of the CLA process . 133
6.2.1 Introduction . 133
6.2.2 Parameters driving the CLA process . 134
6.2.3 Mathematical model verification and database integration . 134
6.2.4 Finite element model reduction . 134
6.2.5 Checks on the Craig-Bampton matrices and OTM . 135
6.2.6 Frequency cut-off for computed modes . 135
6.2.7 Coupling of the launcher and spacecraft models . 135
6.2.8 Calculation of the generalized responses . 135
6.2.9 Determination of the physical responses . 135
6.2.10 Post-processing . 135
6.2.11 Uncertainty factors . 136
6.3 CLA output and results evaluation . 137
6.3.1 Overview . 137
6.3.2 Guidelines to response parameter selection. 138
6.3.3 Equivalent sine input . 138
6.3.4 Computation of static components from OTM . 138
6.3.5 Relative displacements . 139
6.3.6 Interface mechanical fluxes and overfluxes . 139
6.3.7 Results review, verification and validation . 144
6.3.8 Use of CLA results for structural verification . 145
6.3.9 Reporting . 145
6.4 Ariane 5 coupled loads analysis . 148
6.4.1 Introduction to Ariane 5 CLA . 148
6.4.2 Mission analysis organization and management . 149
6.4.3 CLA events and load cases . 150
6.4.4 Concomitant events and load cases combination . 159
6.4.5 Flight phases and CLA standard load cases . 160
6.4.6 Aspects of the Ariane 5 CLA methodology . 163
6.5 The Arianespace spacecraft qualification process . 165
6.5.1 Introduction . 165
6.5.2 Quasi-static loads . 166
6.5.3 Dynamic environment .
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