ISO/TR 20590:2017

TECHNICAL ISO/TR
REPORT 20590
First edition
2017-02
Space systems - Debris mitigation
design and operation manual for
launch vehicle orbital stages
Systèmes spatiaux - Conception pour l’attenuation des débris et
manuel d’utilisation à étages orbitaux pour les véhicules de lancement
Reference number
©
ISO 2017
© ISO 2017, Published in Switzerland
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ii © ISO 2017 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Related documents and abbreviated terms and symbols . 1
4.1 Overview of ISO debris-related standards . 1
4.2 ISO debris-related standards for launch vehicles as of 2016. 2
4.3 Spacecraft related ISO standards . 2
4.4 Other ISO standards . 3
4.5 Other documents . 3
4.6 Abbreviated terms . 3
5 Requirements in ISO Standards and system-level methodologies for complying with
the requirements . 5
5.1 General . 5
5.2 Refrain from releasing objects . . 5
5.2.1 Requirements . 5
5.2.2 Work breakdown . 6
5.2.3 Identification of released objects and design measures . 6
5.3 Break-up prevention . 7
5.3.1 Requirements . 7
5.3.2 Work breakdown . 7
5.3.3 Identification of the sources of break-up . 8
5.3.4 Design measures . 8
5.3.5 Monitoring during operations . 9
5.3.6 Preventive measures for break-up after mission completion . 9
5.4 Disposal manoeuvres at the end of operation . 9
5.4.1 Requirements . 9
5.4.2 Work breakdown .10
5.4.3 LEO mission .11
5.4.4 GEO mission and other high-elliptical orbit missions .12
5.5 Ground safety from re-entering objects .13
5.5.1 Requirements .13
5.5.2 Work breakdown .13
5.5.3 Preventive measures .14
5.5.4 Risk detection: Notification .15
5.5.5 Countermeasures: Controlled re-entry and Monitoring.16
5.6 Collision avoidance .16
5.7 Reliability and QA .16
6 Debris-related work in the development lifecycle .17
6.1 General .17
6.2 Concept of debris-related work in each phase .17
6.3 Mission Requirements Analysis Phase (pre-phase A).20
6.3.1 General.20
6.3.2 Debris-related works .20
6.4 Feasibility phase (phase A) .20
6.5 Definition phase (phase B) .20
6.5.1 Work in phase B .20
6.5.2 Work procedure .21
6.6 Development phase (phase C) .21
6.7 Production phase (phase D) .22
6.7.1 Work in phase D .22
6.7.2 Qualification review .22
6.7.3 Launch service .22
6.8 Utilization phase (phase E) .22
6.9 Disposal Phase (phase F) .22
7 System-level considerations .23
7.1 System design.23
7.2 Mission analysis for each launch mission .23
8 Subsystem / Component design and operation .23
8.1 General .23
8.1.1 Scope .23
8.1.2 Debris-mitigation measures and subsystem-level actions for realizing them .24
8.2 Propulsion subsystem .24
8.2.1 Debris-related design .24
8.2.2 Considerations for propulsion subsystems .25
8.2.3 Considerations for component design .26
8.3 Guidance and control subsystem .28
8.3.1 Debris-related designs .28
8.3.2 Considerations for the guidance and control subsystem .28
8.4 Electric power-supply subsystem .29
8.4.1 Debris related design .29
8.4.2 Considerations for power subsystems .29
8.4.3 Consideration in component design .29
8.5 Communication subsystem .30
8.5.1 Debris-related designs .30
8.5.2 Design of communication subsystem .30
8.5.3 Considerations for component design .30
8.6 Structure subsystem .31
8.6.1 Design measures .31
8.6.2 Practices for structure subsystem .31
8.6.3 Considerations for component design .31
8.7 Range safety subsystem (Self-destruct subsystem) .32
8.7.1 Debris-related designs .32
8.7.2 Consideration for command destruction subsystem .32
8.7.3 Considerations for component design .32
Bibliography .33
iv © ISO 2017 – All rights reserved

Foreword
The International Organization for Standardization (ISO) is a worldwide federation of national
standards bodies (ISO member bodies). International Standards are generally prepared by ISO technical
committees. Each member body interested in a subject for which a technical committee has been
established has the right to represent that committee. International organizations, both 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 the conformity
assessment, as well as information about ISO’s adherence to the World Trade Organization (WTO)
principles in the Technical Barriers to Trade (TBT).
The committee responsible for this document is ISO/TC 20, Aircraft and space vehicles, Subcommittee
SC 14, Space systems and operations.
Introduction
Coping with debris is essential to preventing the deterioration of the orbital environment and ensuring
the sustainability of space activities. Effective actions can also be taken to ensure the safety of those on
the ground from re-entering objects that were disposed of from Earth orbit.
ISO 24113 “Space debris mitigation requirements,” and other ISO documents, introduced in Clause 4,
were developed to encourage debris mitigation. 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 United Nations (UN)
guidelines.
Table 1 lists the main debris mitigation requirements defined in the standards and compares them to
equivalent recommendations published by the UN and the IADC.
In Clause 5, the main space debris mitigation requirements are reported and analyzed.
In Clause 6, the guidance for life-cycle implementation of space debris mitigation related activities are
provided.
In Clause 7, the system level aspects stemming from the space debris mitigation requirements are
highlighted; while in Clause 8, the impacts at subsystem and component levels are detailed.
In this document, where the content is not directly required by existing ISO Standards but considered
relevant to launch vehicle orbital stages operations or design and debris mitigation, it is labelled as
“[Information].”
vi © ISO 2017 – All rights reserved

Table 1 — Comparison of ISO debris-related documents with UN and IADC space debris mitigation guidelines
Measures ISO Standards (or Technical Reports) UN Guidelines IADC Guidelines
Limiting Released General measures for avoiding ISO 24113, 6.1.1 Recommendation-1 5.1
debris gener- objects the release of objects
ation
Slag from solid motors ISO 24113, 6.1.2.2, 6.1.2.3 -- --
Combustion products from ISO 24113, 6.1.2.1 -- --
pyrotechnics
(Combustion Products < 1 mm)
On-orbit- Intentional destruction ISO 24113, 6.2.1 Recommendation-4 5.2.3
al break-
Accidental break-ups during ISO 24113, 6.2.2 Recommendation-2 5.2.2
ups
operation (Monitoring)
-3
(Probability < 10 )
Post-mission break-up ISO 24113, 6.2.2.3 (Detailed in ISO 16127) Recommendation-5 5.2.1
(Passivation, etc.)
Disposal at GEO Reorbit at end of operation  ISO 24113, 6.3.2 (Detailed in ISO 26872) Recommendation-7 5.3.1
end-of-opera-
6.3.2.1: General Requirement (No quantitative requirements) 235 km+
tions
(1 000•Cr•A/m),
6.3.2.2: 235 km+ (1 000•Cr•A/m), e < 0,003 Note: ITU-R S.1003-1 recom-
mends; 235 km + 1,000 Cr*A/M e < 0,003
6.3.1: Success Probability > 0,9
Here, A[m ], M[kg], Cr[-]
LEO Reduction of orbital lifetime ISO 24113, 6.3.3 (Detailed in ISO 16164, 16699) Recommendation-6 5.3.2
6.3.3.1: Orbital lifetime after end of operation (No quantitative requirements) (Recommend 25
years)
< 25 years
6.3.1: Success Probability > 0,9
Transfer to out of protected ISO 24113, 6.3.3.2 (f) Mentioned in Recommendation-6 5.3.2
region
(Guarantee 100 years of 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 only) Recommendation-3 5.4
Protection from the impact of micro-debris ISO 16126 (for assessment only) -- 5.4

TECHNICAL REPORT ISO/TR 20590:2017(E)
Space systems - Debris mitigation design and operation
manual for launch vehicle orbital stages
1 Scope
This document contains non-normative information on the design and operational practices for launch
vehicle orbital stages for mitigating space debris.
This document can be used to guide engineers in the application of the family of space debris mitigation
standards (see 4.2) to reduce the growth of space debris by ensuring that launch vehicle orbital stages
are designed, operated, and disposed of in a manner that prevents them from generating debris
throughout their orbital lifetime.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10795:2011 and the other
standards listed in 4.2, 4.3, and 4.4 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
4 Related documents and abbreviated terms and symbols
4.1 Overview of ISO debris-related standards
The requirements, recommendations, and best practices for mitigating debris generation and
preventing other debris related problems are examined in this clause.
Figure 1 shows a general diagram of major ISO documents related to debris.
Figure 1 — Structure of major debris related standards for orbital stages
4.2 ISO debris-related standards for launch vehicles as of 2016
The following ISO Standards have been developed to address space debris mitigation. Readers are
expected to confirm the most up to date list of ISO standards (available at http:// www .iso .org/ iso/
store .htm. Also for 4.3 − 4.5).
(1) ISO 24113:2011, Space systems — Space debris mitigation requirements
(2) ISO 27852:2011, Space systems — Estimation of orbit lifetime
(3) ISO 16699:2015, Space systems — Disposal of orbital launch stages
(4) ISO 20893, Space systems — Prevention of break-up of orbital launch stages
4.3 Spacecraft related ISO standards
(1) ISO 16127:2014, Space systems — Prevention of break-up of unmanned spacecraft
(2) ISO 16164:2015, Space systems — Disposal of satellites operating in or crossing LEO
(3) ISO 26872:2010, Space systems — Disposal of satellites operating at geosynchronous altitude
2 © ISO 2017 – All rights reserved

4.4 Other ISO standards
The following ISO Standards are not specific to space debris mitigation. However, they are considered
pertinent:
(1) ISO 27875:2010, Space systems — Re-entry safety control for unmanned spacecraft and launch vehicle
orbital stages
(2) ISO 14300-1:2011, Space systems — Programme management – Part 1: Structuring of a project
(3) ISO 14300-2:2011, Space systems — Product assurance — Policy and principles
(4) ISO 14623:2003, Space systems — Pressure vessels and pressurized structures - Design and operation
(5) ISO 27025:2010, Programme management —Quality assurance requirements
(6) ISO 10795:2011, Space systems – Programme management and quality –Vocabulary
(7) ISO/TR 16158:2013, Space systems — Avoiding collisions among orbiting objects: Best practices, data
requirements, and operational concept
4.5 Other documents
The following documents are referenced to understand the background of the ISO documents:
(1) 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
ht t p:// w w w .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 ht t p:// w w w .iadc -online .org/ index .cgi ?item = docs _pub
4.6 Abbreviated terms
A/m Area-to-Mass Ratio
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)
DRAMA Debris Risk Assessment and Mitigation Analysis (ESA)
e Eccentricity
Ec Expected number of casualties
EOMDP End-of-Mission (Operation) Disposal Plan
EOL End-of-Life
ESA European Space Agency
FMEA Failure Mode and Effect Analysis
GEO Geosynchronous Earth Orbit
GTO Geosynchronous Transfer Orbit
IADC Inter-Agency Space Debris Coordination Committee
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
NM Notice to Mariners
NSS NASA Safety Standard
ORDEM Orbital Debris Engineering Model
PDR Preliminary Design Review
QA Quality Assurance
QR Qualification Review
S/C Spacecraft
SDR System Definition Review
SDMP Space-Debris-Mitigation Plan
STELA Semi-analytic Tool for End of Life Analysis (CNES)
STSC Scientific and Technical Subcommittee (UNCOPUOS)
USSTRATCOM United States Strategic Command
TR Technical Report (a type of ISO document)
UN United Nations
4 © ISO 2017 – All rights reserved

5 Requirements in ISO Standards and system-level methodologies for complying
with the requirements
5.1 General
To accomplish comprehensive activities for debris mitigation work, the following steps are considered:
(1) Identifying debris related requirements, recommendations, and best practices.
(2) Determining how to comply with requirements, recommendations, and best practices.
(3) Applying debris mitigation measures early and throughout development and manufacturing to
assure sound debris mitigation capability in the final product.
(4) Applying appropriate QA and qualification programs to ensure compliance with debris mitigation
requirements.
This clause provides methodologies for taking comprehensive action at the system level. More detailed
information for action at the subsystem and component levels is provided in Clause 8. The following
specific subjects are emphasized:
(1) Limiting the release of objects into the useful orbital regions.
(2) Preventing fragmentation in orbit.
(3) Proper disposal during the end of operation.
(4) Minimization of hazards on the ground from re-entering debris.
(5) Collision avoidance for manned or man-able systems.
(6) Quality, safety, and reliability assurance.
5.2 Refrain from releasing objects
5.2.1 Requirements
ISO 24113, 6.1, requires avoiding the intentional release of space debris into Earth orbit during normal
operations:
(1) General;
a) S/C 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 (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) 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 yo-yo de-spinners and 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 the requirements in 6.1.1.1,
the orbital lifetime of such objects in LEO and the interference with GEO is to be limited as described in
ISO 24113, 6.1.1.2 (a typical example is the support structure utilized in a multiple payloads mission).
5.2.2 Work breakdown
Table 2 shows the work breakdown as delineated in ISO 24113 to prevent the release of debris.
Table 2 — Work breakdown for preventing the release of debris
Process Subjects Major work
Preventive measures Identification of a) Take preventive design to avoid releasing objects that would turn
released objects and into space debris. (ISO 24113, 6.1)
design measures
b) If objects might be released unintentionally, designers should in-
vestigate design problems and take appropriate action during design.
c) If release is unavoidable, designers should estimate the orbital lifetime
of released objects and check compliance with 6.1.1.2.
Corrective action Troubleshooting [Reference: If an object would be released unexpectedly, it is recom-
mended to investigate and take appropriate action to avoid repeating
the release in the following missions.]
5.2.3 Identification of released objects and design measures
As ISO 24113 states, launch vehicle designers shall avoid intentional release of space debris objects.
If there are unavoidable reasons (such as, for example, serious technical problems), such objects are
identified and their orbital lifetimes estimated and minimized.
(1) Mission related objects
Release of the following objects shall be avoided (ISO 24113, 6.1.1):
a) Nozzle closures for propulsion devices and certain types of igniters for solid motors, which are
ejected into space after ignition (particularly if their orbital lifetimes are longer than 25 years).
b) Clamp bands that tie the S/C and launch vehicles
c) Structural elements that support the upper S/C used in multi-payloads launches
[Remark: Usually allowed if release is unavoidable and the object’s orbit lifetime will be short; in which
case the disposal orbit of these elements complies with ISO 24113, 6.1.1.2.]
(2) Combustion products from pyrotechnic devices
Adequately designed devices are selected to avoid the release of combustion products. It is possible to
apply parts that trap all combustion products larger than 1 mm inside for segregation.
(3) Combustion products from solid motors
ISO 24113 requires that solid motors do not generate slag in a GEO. On the other hand, for LEO, although
this is not directly prohibited, it is recommended to consider using methods to avoid the release of
6 © ISO 2017 – All rights reserved

slag. To prevent the generation of slag, the first option is to design nozzles adequately so that there is
no pocket at the upstream of the nozzle that may trap melting metals. Another solution is to develop
propellants that do not contain metal (e.g. aluminium).
The orbital lifetime of released objects is assessed as specified in ISO 27852. This International Standard
designates acceptable analysis methodologies the user employs dependent upon the orbit regime.
The available simplified tools that may be admissible (depending upon orbit regime and ISO 27852
requirements) to estimate the long-term orbital lifetime are:
— NASA Debris assessment software (DAS) https:// orbitaldebris .jsc .nasa .gov/ Mitigation/ das .html);
— ESA DRAMA (an account at https:// sdup .esoc .esa .int must be created to obtain a license before
downloading); or
— CNES STELA (https:// logiciels .cnes .fr/ content/ s t el a ? l a n g u a ge = en).
5.3 Break-up prevention
5.3.1 Requirements
ISO 24113 requires that break-ups be prevented as specified in ISO 24113, 6.2:
(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 life.
b) The determination of accidental break-up probability shall quantitatively consider all known
failure modes for the release of stored energy, excluding those from external sources such as
impacts with space debris and meteoroids.
c) During the disposal phase, a spacecraft or launch vehicle orbital stage shall permanently
deplete or make safe all remaining on-board sources of stored energy in a controlled sequence.
While ISO 16127 specifically addresses the prevention of S/C break-ups, it also provides useful
information and procedures for preventing launch vehicle break-up (ISO 20893).
5.3.2 Work breakdown
Table 3 shows the work breakdown as delineated in ISO 24113 to prevent orbital break-up.
Table 3 — Work breakdown for preventing orbital break-ups
Process Subjects Major work
Preventive measures Identification of Identify components that may cause fragmentation during or
sources of breakup after operation.
Design measures (1) Develop preventive designs to limit the probability of acciden-
−3
tal break-up during operation no greater than 10 . Confirm it
with FMEA.
(2) Provide functions to prevent break-ups after disposal.
(3) A self-destruct system should be designed to prevent uninten-
tional destruction caused by miss-command or solar heating.
Risk detection Monitoring during The monitoring function is provided under the flight safety re-
operation quirement aspect.
After passing the flight safety range, some parameters are mon-
itored to ensure performance, and functions for completing the
mission and disposal actions, including controlled re-entry, are
conducted.
Actions in operation Preventive measures Energy sources for break-up should be removed (residual propel-
phase for break-up lants, high-pressure gas, etc.) or designed to be safe so as not to
cause break-ups after the end of operation.
5.3.3 Identification of the sources of break-up
The following launch vehicle subsystem elements can potentially cause break-ups:
— propulsion sub-systems and associated components (Rocket engines and solid motors, tanks, tank
pressurizing systems, valves, piping, etc.);
— electrical batteries;
— pressure vessels and other equipment (such as pneumatic control systems, etc.); and
— self-destruct systems for range safety.
5.3.4 Design measures
The following aspects are to be incorporated into launch vehicle design.
(1) Avoiding intentional break-up
Missions that involve intentional break-ups that can potentially eject fragments into outer space are
prohibited unless required to prevent potential loss of human life after re-entry
(2) Avoiding accidental break-ups during operation
−3
Per ISO 24113, the probability of accidental break-up must be no greater than 10 until its EOL.
“ISO 16127 Space systems - Prevention of break-up of unmanned spacecraft” is designed to apply to the
S/C, but its “Annex - A Procedure for Estimating Break-up Probability” provides adequate instruction to
engineers who wonder how to cope with complicated subsystems such as liquid rocket engines.
To prevent the unintentional explosion of self-destruct charges, the Command Destruct Receivers are
recommended to be turned off after passing through range safety areas to prevent explosion by miss-
command.
(3) Preventing break-ups that occur after the end of operation
8 © ISO 2017 – All rights reserved

The following items are the typical measures to prevent fragmentation for each of the items identified
in 5.3.3. More detailed guidelines for each sub-system or component are described in Clause 8.
a) Residual propellants in the propulsion systems and associated components
— Burning residual propellants to depletion.
— Venting residual propellant until its amount is insufficient to cause a break-up by ignition or
pressure increase from tanks and lines.
b) High pressure fluids
— Venting pressurized systems
c) Range safety systems
— Prevention from inadvertent commands, thermal heating, or radio frequency interference
5.3.5 Monitoring during operations
ISO 16127, 4.3.1, requires monitoring of critical parameters to detect the symptoms that can lead to
break-up, loss of mission capability, or the loss of orbit and attitude control function, and requires
immediate action to be taken when any symptoms are detected. However, it is not usually feasible
for launch vehicles because they are designed to have very limited functions available to terminate
operation during flight, except for range safety operations.
5.3.6 Preventive measures for break-up after mission completion
After separation of payloads, the major sources of break-ups (examples listed in 5.3.3) should be
mitigated (vented or operated in safe mode) according to ISO 16127, 4.4.
Residual propellants and other fluids, such as pressurants, should be depleted as thoroughly as
possible, by either depletion burns or venting, to prevent accidental breakups by over pressurization
or chemical reaction. Opening fluid vessels and lines to the space environment, directly or indirectly, at
the conclusion of EOM passivation, is one way to reduce the possibility of a later explosion.
5.4 Disposal manoeuvres at the end of operation
5.4.1 Requirements
ISO 24113, 6.3 requires removing an S/C or launch vehicle orbital stage from the protected regions
after EOM as follows:
(1) Probability of successful disposal
a) The probability of successful disposal of a spacecraft or launch vehicle orbital stage shall be at
least 0,9 at the time disposal is executed.
b) The probability of successful disposal shall be evaluated as conditional probability weighted
on the mission success.
c) The start and end of the disposal phase shall be chosen so that all disposal actions are
completed within a period of time that ensures compliance with above a).
(2) GEO disposal maneuvers
a) A spacecraft or launch vehicle orbital stage operating in the GEO protected region (defined in
ISO 24113), with either a permanent or periodic presence, shall be maneuvered in a controlled
manner during the disposal phase to an orbit that lies entirely outside the GEO protected region.
b) A spacecraft operating within the GEO protected region shall, after completion of its GEO
disposal maneuvers, have an orbital state that satisfies at least one of the following two
conditions:
· the orbit has an initial eccentricity less than 0,003, and a minimum perigee altitude, ∆H (in
km), above the geostationary altitude in accordance with
∆H = 235 + 1 000 Cr A/m
· the orbit has a perigee altitude sufficiently above the geostationary altitude that long-term
perturbation forces do not cause the spacecraft to enter the GEO protected region within
100 years.
(3) LEO disposal maneuvers
a) A spacecraft or launch vehicle orbital stage operating in the LEO protected region (defined in
ISO 24113), with either a permanent or periodic presence, shall limit its post-mission presence
in the LEO protected region to a maximum of 25 years from the end of mission.
b) After the end of mission, the removal of a spacecraft or launch vehicle orbital stage from
the LEO protected region shall be accomplished by one of the following means (in order of
preference):
i) retrieving it and performing a controlled re-entry to recover it safely on the Earth, or
ii) manoeuvering it in a controlled manner into a targeted re-entry with a well-defined impact
footprint on the surface of the Earth to limit the possibility of human casualty, or
iii) manoeuvering it in a controlled manner to an orbit with a shorter orbital lifetime that is
compliant with above a), or
iv) augmenting its orbital decay by deploying a device so that the remaining orbital lifetime is
compliant with above a), or
v) allowing its orbit to decay naturally so that the remaining orbital lifetime is compliant
with above a), or
vi) manoeuvering it in a controlled manner to an orbit with a perigee altitude sufficiently
above the LEO protected region that long-term perturbation forces do not cause it to re-
enter the LEO protected region within 100 years.
[Information]: For an S/C, ISO 26872 provides more detailed requirements and procedures for the
disposal of GEO missions to comply with the high-level requirements stated in ISO 24113, and ISO 16699
provides more detailed requirements and procedures for the disposal of launch vehicle orbital stages in
LEO missions.
5.4.2 Work breakdown
Table 4 shows the work breakdown as delineated in ISO 24113 to protect orbital regions:
10 © ISO 2017 – All rights reserved

Table 4 — Work breakdown for the preservation of the LEO-protected region
Process Subjects Major work
Preventive meas- Estimate the orbital Estimate the orbital lifetime after payload separation, and define a
ures lifetime and define a disposal maneuver plan.
disposal plan
Disposal planning One of the following methods is applied. (ISO 16699):
(1) Controlled re-entry
(2) Maneuvering to reduce the orbital lifetime
(3) Augmenting its orbital decay by deploying a device
(4) Allowing its orbit to decay naturally
(5) Maneuvering it to an orbit with a perigee altitude sufficiently
above the LEO protected region
Disposal function Functions and resources to remove orbital stages (examples:
and resources restart function
...