ISO/TR 18146:2015

Space systems - Space debris mitigation design and operation guidelines for spacecraft

ISO/TR 18146:2015 contains non-normative information on spacecraft design and operational practices for mitigating space debris. ISO/TR 18146:2015 is a supporting document to the family of international standards addressing space debris mitigation (see 2.2). The purpose of these standards is to minimize the creation of additional space debris by ensuring that spacecraft and launch vehicle orbital stages are designed, operated and disposed of in a manner that prevents them from generating debris throughout their orbital lifetime. ISO/TR 18146:2015 can be used to guide spacecraft engineers in the application of these space debris mitigation standards. Table 1 lists the main debris mitigation requirements defined in the standards and compares them to equivalent recommendations published by the United Nations and the Inter-Agency Space Debris Coordination Committee.

Systèmes spatiaux — Conception de mitigation des débris spatiaux et lignes directrices de manoeuvre de la navette

General Information

• Status: Withdrawn
• Publication Date: 30-Sep-2015
• Withdrawal Date: 30-Sep-2015
• ICS: 49.140 - Space systems and operations
• Technical Committee: ISO/TC 20/SC 14 - Space systems and operations
• Drafting Committee: ISO/TC 20/SC 14 - Space systems and operations
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 26-Oct-2020
• Completion Date: 13-Dec-2025

Relations

• Revised: ISO/TR 18146:2020 - Space systems - Space debris mitigation design and operation manual for spacecraft
• Effective Date: 23-Apr-2020

Standards Content (Sample)

TECHNICAL ISO/TR
REPORT 18146
First edition
2015-10-01
Space systems — Space debris
mitigation design and operation
guidelines for spacecraft
Systèmes spatiaux — Conception de mitigation des débris spatiaux et
lignes directrices de manoeuvre de la navette
Reference number
©
ISO 2015
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
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ii © ISO 2015 – All rights reserved

Contents Page
Foreword .vi
Introduction .vii
1 Scope . 1
2 Related documents and abbreviated terms and symbols . 3
2.1 Overview of ISO debris-related standards . 3
2.2 ISO debris-related standards as of February 2015 . 3
2.3 Other relevant ISO standards . 4
2.4 Other documents . 4
2.5 Abbreviated terms and symbols . 5
3 Requirements in ISO standards and system-level methodologies for complying with them 6
3.1 General . 6
3.2 Design for limiting the release of objects . 7
3.2.1 Requirements . 7
3.2.2 Work breakdown . 8
3.2.3 Identification of released objects and design measures . 8
3.2.4 Design measures . 9
3.2.5 Monitoring during operation . 9
3.2.6 Preventing failure . 9
3.3 Break-up prevention .10
3.3.1 Requirements .10
3.3.2 Work breakdown .10
3.3.3 Identification of the sources of break-up .10
3.3.4 Design measures .11
3.3.5 Monitoring during operations .11
3.3.6 Disposal operations .11
3.4 Disposal at the end of operation .11
3.4.1 Requirements .11
3.4.2 Work breakdown .12
3.4.3 Estimation of the orbital lifetime and definition of a disposal plan .13
3.4.4 Function to remove spacecraft to disposal orbit. .14
3.4.5 Reliability of accomplishing disposal manoeuvre .14
3.4.6 Function to monitor critical parameters .15
3.4.7 Decision-making to terminate operations and for execution of
disposal operations .15
3.4.8 Disposal sequence .15
3.4.9 Registration according to the UN treaty .15
3.4.10 Specific subjects for GEO mission .15
3.5 Ground safety from re-entering objects .15
3.5.1 Requirements .15
3.5.2 Work breakdown .15
3.5.3 Identification of requirements .16
3.5.4 Hazards analysis .16
3.5.5 Design measures .17
3.5.6 Specific design for controlled re-entry in subsystem level .18
3.5.7 Notification .18
3.5.8 Conduct controlled re-entry and monitoring .18
3.6 Collision avoidance .18
3.6.1 Background.18
3.6.2 Recommendation .19
3.6.3 Work breakdown .19
3.6.4 Estimation of collision probability .20
3.6.5 Design measures .20
3.6.6 Procedures for collision avoidance .21
3.6.7 Detection of risk .21
3.6.8 Avoidance and return manoeuvres .21
3.7 Protection against the impact of micro-debris .22
3.7.1 Background.22
3.7.2 Recommendation .23
3.7.3 Work breakdown .23
3.7.4 Preventive measures .23
3.8 Quality and reliability assurance .24
4 Debris-related work in the development cycle .25
4.1 Concept of debris-related work in phased planning .25
4.2 Mission analysis phase (phase 0 or pre-phase A) .28
4.2.1 General.28
4.2.2 Debris-related work .28
4.3 Feasibility phase (phase A) .29
4.4 Definition phase (phase B) .29
4.4.1 Work in phase B .29
4.4.2 Work procedure .29
4.5 Development phase (phase C) .30
4.5.1 Work in phase C .30
4.5.2 Conditions .31
4.6 Production phase (phase D) .31
4.6.1 Work in phase D .31
4.6.2 Qualification review .32
4.7 Utilization phase (phase E) .32
4.7.1 Launch preparation .32
4.7.2 Lift-off time .33
4.7.3 Initial operation .33
4.7.4 Normal operation .33
4.7.5 Decision to terminate operations .33
4.7.6 Process for extending mission operations .34
4.8 Disposal phase (phase F) .34
5 System-level considerations .35
5.1 Mission design .35
5.2 Mass allocation .35
5.3 Propellant allocation .36
5.4 Power allocation .36
6 Subsystem/component design and operation .36
6.1 General .36
6.2 Debris-mitigation measures and subsystem-level actions for realizing them .37
6.3 Propulsion subsystem .37
6.3.1 Debris-related design .37
6.3.2 Considerations for propulsion subsystems .37
6.3.3 Consideration in component design .41
6.4 Attitude and orbit control subsystem .43
6.4.1 Debris-related designs .43
6.4.2 Considerations for AOCS .43
6.4.3 Considerations in component design.44
6.5 Power-supply subsystem .44
6.5.1 Debris-related designs .44
6.5.2 Considerations for power-supply subsystems .45
6.5.3 Considerations in component design.46
6.6 TT&C subsystem .47
6.6.1 Debris-related designs .47
6.6.2 Considerations for TT&C subsystems .47
6.6.3 Considerations in component design.48
6.7 Structural subsystem .48
6.7.1 Debris-related design .48
iv © ISO 2015 – All rights reserved

6.7.2 Considerations for structural subsystems .49
6.8 Thermal-control subsystem .49
6.8.1 Debris-related design .49
6.8.2 Considerations for thermal-control subsystem .50
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received. www.iso.org/patents
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 20, Aircraft and space vehicles, Subcommittee
SC 14, Space systems and operations.
vi © ISO 2015 – All rights reserved

Introduction
Coping with debris is essential to preventing the deterioration of the orbital environment and ensuring
the sustainability of space activities. Effective actions must also be taken to ensure the safety of those
on the ground from re-entering objects that were disposed of from low-Earth orbit.
Recently, the orbital environment has become so deteriorated by debris that action must be taken to
prevent damage due to the impact. Collision avoidance manoeuvres should be taken to avoid large
debris (larger than 10 cm, for example), which can be observed from the ground. Spacecraft design
should protect against micro-debris (even smaller than 1 mm) that can cause critical damage to
vulnerable components.
The following ISO standards and technical reports cover these issues: ISO 24113, Space systems — Space
debris mitigation requirements; ISO/TR 16158, Space systems — Avoiding collisions with orbiting objects;
ISO 16126, Space systems — Assessment of the survivability of unmanned spacecraft against space debris
and meteoroid impacts to ensure successful post-mission disposal. Other ISO documents, introduced in
Clause 2, are currently being developed to encourage debris mitigation and protection from debris
impact. Table 1 shows those requirements together with the recommendations in the United Nations
Space Debris Mitigation Guidelines and the Inter-Agency Space Debris Coordination Committee (IADC)
space debris guidelines referred to in the UN guidelines.
Reliability and quality shortfalls have resulted in fragmentation events that generated thousands
of fragments. ISO 24113 and other debris-mitigation guidelines make the assumption that space
hardware quality and reliability issues have been addressed by other management programs. But for
low-cost or low-criticality missions, spacecraft of reduced quality have been developed. The failure
of such spacecraft may not pose critical damage to their owners but they may adversely affect the
environment and impair the sustainability of space activities. This Technical Report suggests activities
that can improve reliability and quality sufficiently to avoid this problem. This aspect of space-debris
mitigation is particularly important for micro-satellites developed by universities and newcomers to
space activities.
TECHNICAL REPORT ISO/TR 18146:2015(E)
Space systems — Space debris mitigation design and
operation guidelines for spacecraft
1 Scope
This Technical Report contains non-normative information on spacecraft design and operational
practices for mitigating space debris.
This Technical Report is a supporting document to the family of international standards addressing
space debris mitigation (see 2.2). The purpose of these standards is to minimize the creation of
additional space debris by ensuring that spacecraft and launch vehicle orbital stages are designed,
operated and disposed of in a manner that prevents them from generating debris throughout their
orbital lifetime.
This Technical Report can be used to guide spacecraft engineers in the application of these space debris
mitigation standards. Table 1 lists the main debris mitigation requirements defined in the standards
and compares them to equivalent recommendations published by the United Nations and the Inter-
Agency Space Debris Coordination Committee.
In Clause 3, the main space debris mitigation requirements are reported and discussed. Clause 4
provides guidance for life-cycle implementation of space debris mitigation related activities.
In Clause 5, the system level aspects stemming from the space debris mitigation requirements are
highlighted, while in Clause 6, the impacts at subsystem and component levels are detailed.
Where it is not directly required by existing ISO standards but considered relevant to spacecraft
operations, design and debris mitigation, content in this Technical Report is labelled as such with
“[information]”.
2 © ISO 2015 – All rights reserved
Table 1 — Comparison of ISO debris-related documents with UN and IADC space debris mitigation Guidelines
Measures  ISO International Standards (or Technical Reports) UN Guidelines IADC Guidelines
General measures for avoiding the
ISO 24113, 6.1.1 Recommendation-1 5.1
release of objects
Operational debris Included in above Included in above 5.1
Released objects
Slag from solid motors ISO 24113, 6.1.2.2, 6.1.2.3 -- --
ISO 24113, 6.1.2.1
Combustion products from pyrotechnics -- --
(Combustion Products < 1 mm)
Intentional destruction ISO 24113, 6.2.1 Recommendation-4 5.2.3
ISO 24113, 6.2.2
5.2.2
On-orbital break- Accident during operation Recommendation-2
(Monitoring)
-3
(Probability < 10 )
ups
Post-mission break-up (Passivation,
ISO 24113, 6.2.2.3 (Detailed in ISO 16127) Recommendation-5 5.2.1
etc.)
Recommendation-7
ISO 24113, 6.3.2 (Detailed in ISO 26872)
5.3.1
Disposal at end of (No quantitative requirements)
6.3.2.1: General Requirement.
operation
Reorbit at EOL 235 km+ (1000·Cr·A/m),
Note: ITU-R S.1003-1 recommends; 235
6.3.2.2: 235 km+ (1000·Cr·A/m), e < 0,003
GEO km + 1000 Cr*A/M
e < 0,003
6.3.1: Success Probability > 0,9
Here, A[m ], M[kg], Cr[-]
ISO 24113, 6.3.3 (Detailed in ISO 16164)
Recommendation-6 5.3.2
Reduction of orbital lifetime 6.3.3.1: EOL Lifetime < 25 years
(No quantitative requirements) (Recommend 25 years)
Disposal at end of
6.3.1: Success Probability > 0,9
operation
ISO 24113, 6.3.3.2 (f)
LEO
Transfer to graveyard Mentioned in recommendation-6 5.3.2
(guarantee 100 years’ non-interference)
Other options ISO 24113, 6.3.3.2 (a) ~ (e) -- 5.3.2
Re-entry Avoidance of ground casualties  ISO 24113, 6.3.4 (Detailed in ISO 27875) Included in Recommendation-6 5.3.2
Collision avoidance for large debris  ISO/TR 16158 (for assessment) Recommendation-3 5.4
Protection from the impact of micro-debris       ISO 16126 (for assessment) -- 5.4

2 Related documents and abbreviated terms and symbols
2.1 Overview of ISO debris-related standards
The requirements, recommendations, and best practices for mitigating debris generation and
preventing other debris related problems are now examined.
Figure 1 shows a general diagram of major ISO documents relevant to debris.
Figure 1 — Structure of major ISO debris-related standards
2.2 ISO debris-related standards as of February 2015
The following ISO standards have been published to address space debris mitigation:
(1) ISO 11227:2012, Space systems — Test procedures to evaluate spacecraft material ejector upon
hypervelocity impact
(2) ISO 14200:2012, Space environment (natural and artificial) — Guide to process-based
implementation of meteoroid and debris environmental models (orbital altitude below GEO + 200 km)
(3) ISO 16126:2014, Space systems — Assessment of survivability of unmanned spacecraft against
space debris and meteoroid impacts to ensure successful post-mission disposal
(4) ISO 16127:2014, Space systems — Prevention of break-up of unmanned spacecraft
(5) ISO 16164:2015, Space systems — Disposal of satellites operating in or crossing Low Earth Orbit
(6) ISO 23339:2010, Space systems — Unmanned spacecraft residual propellant mass estimation for
disposal manoeuvres
(7) ISO 24113:2011, Space systems — Space debris mitigation requirements
(8) ISO 26872:2010, Space systems — Disposal of satellites operating at geosynchronous altitude
(9) ISO 27852:2011, Space systems — Estimation of orbit lifetime
(10) ISO 27875:2010, Space systems — Re-entry safety control for unmanned spacecraft and launch
vehicle orbital stages
2.3 Other relevant ISO standards
The following ISO standards are not specific to space debris mitigation but are considered relevant:
(1) ISO/TR 11225:2012, Space environment (natural and artificial) — Guide to reference and standard
atmosphere models
(2) ISO/TR 11233:2014, Space systems — Orbit determination and estimation — Process for
describing techniques
(3) ISO 14300-1:2011, Space systems — Programme management — Part 1: Structuring of a project
(4) ISO 14623:2003, Space systems — Pressure vessels and pressurized structures — Design and
operation
(5) ISO/TR 16158:2013, Space systems — Avoiding collisions among orbiting objects: Best practices,
data requirements, and operational concepts
(6) ISO 16404:2013, Space systems — Programme management — Requirements management
(7) ISO 27025:2010, Program management — Quality assurance requirements
2.4 Other documents
The following relevant documents are listed to provide the reader with additional background of the
above ISO standards:
(1) UN, Space Debris Mitigation Guidelines of the Scientific and Technical Subcommittee of the
Committee on the Peaceful Uses of Outer Space, Annex IV of A/AC.105/890, 6 March 2007, endorsed by
the United Nations General Assembly under Resolution A/RES/62/217
(2) IADC Space Debris Mitigation Guidelines, IADC-02-01, Revision 1, September 2007, available at
http://www.iadc-online.org/index.cgi?item=docs_pub
(3) Support Document to the IADC Space Debris Mitigation Guidelines, IADC-04-06, Issue 1, 5 October
2004, available at http://www.iadc-online.org/index.cgi?item=docs_pub
4 © ISO 2015 – All rights reserved

(4) ITU Recommendation on GEO Disposal, ITU-R S.1003, January 2004
(5) IADC-08-03 Sensor system to detect impact on spacecraft (http://www.iadc-online.org/)
2.5 Abbreviated terms and symbols
A/m: Area-to-mass
AOCS: Attitude and Orbit Control System
CDR: Critical Design Review
CFRP: Carbon-Fiber-Reinforced Plastic
CNES: Centre National d’Etudes Spatiales
COPUOS: Committee on the Peaceful Uses of Outer Space
Cr: Solar Radiation Pressure Coefficient
DAS: Debris Assessment Software (NASA)
Draft International Standard (drafting phase in the process in ISO for registration of new
DIS:
standard)
DoF: Degrees-of-Freedom
COTS: Commercial Off-The-Shelf
DRAMA: Debris Risk Assessment and Mitigation Analysis (ESA)
e: eccentricity
EOMDP: End-of-Mission (Operation) Disposal Plan
EOL: End of Life
ESA: European Space Agency
FMEA: Failure Mode and Effect Analysis
GEO: Geosynchronous orbit
GPS: Global Positioning System
GTO: Geosynchronous transfer orbit
IADC: Inter-Agency Space Debris Coordination Committee
IRU: Inertial Reference Unit
ISO: International Organization for Standardization
JAXA: Japan Aerospace Exploration Agency
JSpOC: Joint Space Operations Center (USA)
LEGEND: LEO-to-GEO Environment Debris model
LEO: Low Earth orbit
MASTER: Meteoroid and Space Debris Terrestrial Environment Reference
MEO: Medium Earth orbit
MMOD: Micro-Meteoroid Orbital Debris
NOTAM: Notice To Airmen and Notice to Mariners
NSS: NASA Safety Standard
ORDEM: Orbital Debris Engineering Model
ORSAT: Object Re-entry Survival Analysis Tool
PDR: Preliminary Design Review
PNF: Probability of no Failures
QA: Quality Assurance
QR: Qualification Review
RAAN: Right ascension of the ascending node
RCS: Reaction Control System
S/C: Spacecraft
SCARAB: Space Craft Atmospheric Re-entry and Aerothermal Break-up
SDA: Space Data Association,
SDR: System Definition Review
SDMP: Space-Debris-Mitigation Plan
STELA: Semi-analytic Tool for End of Life Analysis (CNES)
USSTRATCOM: United States Strategic Command
STS: Space Transportation System
TLE: Two-Line Element Set
TR: Technical Report (a type of ISO document)
TT&C: Telemetry Tracking and Command
UN: United Nations
United Nations Committee on the Peaceful Uses of Outer Space Scientific and Technical
UNCOPUOS:
Subcommittee
3 Requirements in ISO standards and system-level methodologies for
complying with them
3.1 General
To accomplish comprehensive activities for debris mitigation and protection work, the following steps
are to be considered:
(1) Identifying debris-related requirements, recommendations and best practices.
(2) Determining how to comply with these requirements, recommendations, and best practices.
6 © ISO 2015 – All rights reserved

(3) Apply those methods early and throughout development and manufacturing to ensure sound debris
mitigation capability in the final product.
(4) Apply appropriate quality assurance and qualification program to ensure compliance with debris
mitigation requirements
This sub-clause provides methodologies for taking comprehensive action at the system level. More
detailed information for action of subsystem and component levels is provided in Clause 6. The
following specific subjects are emphasized:
(1) Limiting the release of objects in protected orbital regions.
(2) Preventing fragmentation in orbit.
(3) Proper disposal during the end of operation to preserve the environment in protected orbital regions.
(4) Minimization of hazard on the ground from re-entering debris.
(5) Collision avoidance for trackable known objects.
(6) Protection against the impact of micro-debris and meteoroid.
(7) Quality, safety and reliability assurance.
3.2 Design for limiting the release of objects
3.2.1 Requirements
ISO 24113, 6.1 requires avoiding the intentional release of space debris into Earth orbit during
normal operations:
(1) For general objects:
a) Spacecraft and launch vehicle orbital stages shall be designed so as not to release space debris
into Earth orbit during normal operations.
b) Space debris released into Earth orbit as part of normal operations, other than as covered by
next (2), shall remain outside the GEO protected region, and its presence in the LEO protected
region shall be limited to a maximum of 25 years after release.
(2) For the combustion-related products:
a) Pyrotechnic devices shall be designed so as to avoid the release into Earth orbit of products
larger than 1 mm in their largest dimension.
b) Solid rocket motors shall be designed and operated so as to avoid releasing solid combustion
products into the GEO protected region.
c) In the design and operation of solid rocket motors, methods to avoid the release of solid combustion
products that might contaminate the LEO protected region shall be considered.
The following classes of released objects are of concern from an orbital debris mitigation standpoint:
(1) Objects released as directed by mission requirements (ISO 24113, 6.1.1).
(2) Mission-related objects, such as fasteners, under the responsibility of designers (ISO 24113, 6.1.1).
(3) Combustion products from pyrotechnic devices (ISO 24113, 6.1.2.1).
(4) Combustion products from solid motors (ISO 24113, 6.1.2.2).
ISO 24113, 6.1.1.2 states that if objects must unavoidably be released despite requirements in ISO 24113,
6.1.1.1, orbital lifetime of such objects in Low Earth Orbit (LEO) and interference with Geostationary
Earth Orbit (GEO) is to be limited as described in ISO 24113, 6.1.1.2. A typical example is the support
structure utilized in multiple payloads mission.
3.2.2 Work breakdown
Table 2 shows the work breakdown for the actions required to prevent the releasing of debris.
Table 2 — Work breakdown for preventing the release of objects
Process Subjects Major work
Preventive measures I de n t i f ic a t io n of (1) Take preventive design to avoid releasing objects turning into
released objects and space debris. (ISO 24113, 6.1)
design measures
(2) If objects might be released unintentionally, designers will
investigate design problems and take appropriate action during
design phase. (Examples: paint flakes, insulators)
(3) If release is unavoidable, designers will estimate the orbital
lifetime of released objects and check compliance with 6.1.1.2.
Risk detection Monitoring during oper- (1) Confirm that the orbiting characteristics of released parts are
ation as estimated, if needed.
(2) If an unexpected object is detected, the origin of the objects
will be confirmed.
Countermeasures Preventive measures If an object is released unexpectedly, it will be investigated and
appropriate action will be taken to avoid repeating the release in
the following missions.
3.2.3 Identification of released objects and design measures
Identify the parts planned to be released, estimate their orbital lifetimes, and determine the propriety
of their release.
(1) Mission requirements that require dispersing objects
Assess the effects of proposed mission requirements on the environment. If the proposed mission
may deteriorate the environment more than justified by its benefit, system engineering may suggest
alternative approaches.
Examples are:
a) The experiment called “WESTFORD NEEDLES,” conducted in 1961 and 1963, scattered 480 million
needles in orbit. More than 100 clumps of needles have been registered and many of them are still
in orbit. The legacy of Project West Ford can still be found in international policies, including the first
major United Nations accord on activities in outer space that calls for international consultations
before undertaking an experiment which might cause “potentially harmful interference with activities
1)
of other State Parties in the peaceful exploration and use of outer space.
b) Missions that conduct intentional fragmentation (one of the major causes of deterioration of the
orbital environment).
(2) Mission-related objects
Release of the following objects shall be avoided by appropriate mission and spacecraft design
(ISO 24113, 6.1.1):
a) fasteners for deploying and holding devices for panels or antennas
b) nozzle closures for propulsion devices and certain types of solid motor igniters
1) [Ref. NASA, JSC, Orbital Debris Quarterly News, Volume 17, Issue 4 October 2013 http://orbitaldebris.jsc.nasa.
gov/]
8 © ISO 2015 – All rights reserved

c) clamp bands that tie spacecraft and launch vehicles (usually as vehicle components)
Remark: The structural elements which support upper spacecraft used in the case of multi-payloads
launching are allowed to be released due to their unavoidability. Disposal orbit of these elements
should be comply with 6.1.1.2. (Note that these elements usually belong to the launch vehicle, not
the spacecraft.)
(3) Combustion products from pyrotechnic devices
Devices should be selected and/or designed to avoid the production and release of combustion by-
products. Employing vehicle components that trap all fragments and combustion products inside
for segregation (ISO 24113, 6.1.2.1).
(4) Combustion products from solid motors
Solid motors should not generate slag in geosynchronous orbit. (ISO 24113, 6.1.2.2)
In very low Earth orbit, particles smaller than 1 cm will decay quickly. But large-sized slag ejected
in LEO at the end of propulsion burns is a concern; generation of this kind of slag can be prevented
by either designing the nozzle adequately to avoid a pocket upstream of the nozzle that may trap
melting metals or to develop propellant that does not contain metal (i.e. aluminium).
3.2.4 Design measures
In general, only devices that do not release parts into the space environment are to be selected. If parts
would be released for unavoidable reasons, the orbital lifetime of the parts and the impact on other
spacecraft should be assessed, and a final decision should be made about whether to proceed with the
mission. The orbital lifetime can be assessed according to ISO 27852. This Technical Report does not
designate a specific analysis tool but rather requires that the user employ specific techniques depending
upon orbit regime, so that designers can select any tool(s) which adhere to ISO 27852 approved
techniques. Available simplified tools that can be used to estimate the long term orbital lifetime are,
for instance: NASA DAS (Debris Assessment Software), ESA DRAMA (Debris Risk Assessment and
Mitigation Analysis) [an account at https://sdup.esoc.esa.int must be created to obtain a license before
downloading], or CNES STELA (Semi-analytic Tool for End of Life Analysis; https://logiciels.cnes.
fr/content/stela?language=en).
3.2.5 Monitoring during operation
[Information] The release of objects should be confirmed by ground-based space tracking facilities to
ensure that they released as expected and that their orbital lifetimes are sufficiently short. The Space
Situation Report provided by US Joint Space Operations Center (JSpOC) provides a good reference.
3.2.6 Preventing failure
[Information] If objects are released unexpectedly, the origin of the objects should be identified to help
prevent recurrence in future missions. Because such phenomena may indicate a malfunction, the situation
should be reviewed carefully and appropriate action taken to prevent further abnormal conditions.
3.3 Break-up prevention
3.3.1 Requirements
ISO 24113 requires the prevention of space object break-ups in 6.2 as follows:
(1) Intentional break-ups
a) In Earth orbit, intentional break-up of a spacecraft or launch vehicle orbital stage shall be avoided.
(2) Accidental break-ups
a) The probability of accidental break-up of a spacecraft or launch vehicle orbital stage shall be no
-3
greater than 10 until its end of
...