SIST EN 9300-100:2018

SLOVENSKI STANDARD
01-oktober-2018
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Aerospace series - LOTAR - Long Term Archiving and Retrieval of digital technical
product documentation such as 3D, CAD and PDM data - Part 100: Common concepts
for Long term archiving and retrieval of CAD 3D mechanical information
Luft- und Raumfahrt - LOTAR - Langzeit-Archivierung und -Bereitstellung digitaler
technischer Produktdokumentationen, wie zum Beispiel von 3D-, CAD- und PDM-Daten -
Teil 100: Allgemeine Konzepte für die Langzeitarchivierung und -Bereitstellung von 3D-
CAD-Mechanik-Informationen
Série aérospatiale - LOTAR - Archivage Long Terme et récupération des données
techniques produits numériques, telles que CAD 3D et PDM - Partie 100 : Concepts
communs pour l'archivage long terme et la récupération des données CAD 3D
méchanique
Ta slovenski standard je istoveten z: EN 9300-100:2018
ICS:
49.020 Letala in vesoljska vozila na Aircraft and space vehicles in
splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 9300-100
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2018
EUROPÄISCHE NORM
ICS 01.110; 35.240.10; 35.240.30; 49.020
English Version
Aerospace series - LOTAR - Long Term Archiving and
Retrieval of digital technical product documentation such
as 3D, CAD and PDM data - Part 100: Common concepts for
Long term archiving and retrieval of CAD 3D mechanical
information
Série aérospatiale - LOTAR - Archivage Long Terme et Luft- und Raumfahrt - LOTAR - Langzeit-Archivierung
récupération des données techniques produits und -Bereitstellung digitaler technischer
numériques, telles que CAD 3D et PDM - Partie 100 : Produktdokumentationen, wie zum Beispiel von 3D-,
Concepts communs pour l'archivage long terme et la CAD- und PDM-Daten - Teil 100: Allgemeine Konzepte
récupération des données CAD 3D méchanique für die Langzeitarchivierung und -Bereitstellung von
3D-CAD-Mechanik-Informationen
This European Standard was approved by CEN on 15 October 2017.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 9300-100:2018 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Foreword . 5
1 Scope . 6
2 Normative references . 7
3 Terms, definitions and abbreviations . 7
4 Applicability . 10
5 Fundamentals and concepts for Long Term Archiving of CAD 3D mechanical
information . 10
6 Document structure of EN 9300-1XX family . 18
7 Qualification methods for long term preservation of archived CAD information . 20
8 Preservation planning of archived CAD information . 23
9 Administration and monitoring . 25
10 Definition of Archive Information Packages for CAD data . 26
Annex A (informative) The Evolution of CAD Systems . 33
Annex B (informative) Overview of the main types of CAD 3D mechanical information . 34
Annex C (informative) Overview of CAD mechanical assembly structure information . 37
Annex D (informative) Template for the table of contents of a part of the family EN 9300-1xx . 40
Annex E (informative) Considerations for long term preservation of CAD 3D information . 42
Annex F (informative) Definition of a representative sample of test cases . 51
Annex G (informative) Example of performance indicators used to manage longevity of CAD
archived information . 54
Annex H (informative) Overview of maturity of the main components for long term
archiving of CAD mechanical information . 57

Figures Page
Figure 1 — 3D annotation .9
Figure 2 — Illustration of the major generations of CAD systems . 10
Figure 3 — Type of CAD essential information to archive, depending on the CAD methods
used . 12
Figure 4 — Links between Use Cases, essential information and EN 9300 1xx parts . 13
Figure 5 — Different levels of commonality of business requirements and use cases. 14
Figure 6 — Long term preservation of CAD and risk management . 16
Figure 7 — Migration strategies . 17
Figure 8 — Detail level of EN 9300 part related to description of fundamentals & concept . 19
Figure 9 — Relationship / linking between the EN 9300-1xx Family . 20
Figure 10 — Mapping of OAIS information package objects onto EN 9300 . 27
Figure 11 — Main files of the PDI with the associated 3D model shape . 30
Figure A.1 — Illustration of generations of CAD systems for mechanical design . 33
Figure B.1 — Definition of a 3D explicit shape representation . 34
Figure C.1 — 3D CAD assembly structure . 37
Figure C.2 — Example for a nested CAD assembly . 37
Figure C.3 — CAD assembly using coordinate placement . 38
Figure C.4 — CAD assembly using mating conditions . 38
Figure C.5 — Explicit 3D CAD assembly structure information which includes GD&T . 38
Figure C.6 — Use cases of CAD assembly archiving . 39
Figure E.1 — Tolerance distance for points . 43
Figure E.2 — Engineering tolerance vs. CAD kernel tolerance . 44
Figure E.4 — View of different levels of information in 3D CAD design . 46
Figure E.5 — Failure to preserve shape following a new CAD system release . 47
Figure E.6 — Representation change due to change of CAD system release . 47
Figure E.7 — CAD archived model as the master model for the released design . 48
Figure E.8 — Main types of use cases of CAD models (STEP archived and native) after
release . 49
Figure G.1 — Example of performance indicators used for the Ingestion process . 55
Figure G.2 — Example of performance indicators used for the Retrieval process . 56
Figure H.1 — Current level of maturity of components for the main types of CAD mechanical
information . 58

European foreword
This document (EN 9300-100:2018) has been prepared by the Aerospace and Defence Industries
Association of Europe - Standardization (ASD-STAN).
After enquiries and votes carried out in accordance with the rules of this Association, this Standard has
received the approval of the National Associations and the Official Services of the member countries of
ASD, prior to its presentation to CEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by January 2019, and conflicting national standards shall
be withdrawn at the latest by January 2019.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Foreword
This European standard was prepared jointly by AIA, ASD-STAN, PDES Inc and the PROSTEP iViP
Association.
The PROSTEP iViP Association is an international non-profit association in Europe. For establishing
leadership in IT-based engineering it offers a moderated platform to its nearly 200 members from
leading industries, system vendors and research institutions. Its product and process data
standardization activities at European and worldwide levels are well known and accepted. The
PROSTEP iViP Association sees this standard and the related parts as a milestone of product data
technology.
PDES Inc is an international non-profit association in USA. The mission of PDES Inc is to accelerate the
development and implementation of ISO 10303, enabling enterprise integration and PLM
interoperability for member companies. PDES Inc gathers members from leading manufacturers,
national government agencies, PLM vendors and research organizations. PDES Inc. supports this
European standard as an industry resource to sustain the interoperability of digital product
information, ensuring and maintaining authentic longevity throughout their product lifecycle.
Readers of this European standard should note that all standards undergo periodic revisions and that
any reference made herein to any other standard implies its latest edition, unless otherwise stated.
The standards will be published under two different standards organizations using different prefixes.
ASD-Stan will publish the standard under the number EN 9300–xxx. AIA will publish the standard
under the number NAS 9300–xxx. The content in the EN 9300 and NAS 9300 documents will be the
same. The differences will be noted in the reference documentation (i.e. for EN 9300 Geometric
Dimensioning & Tolerancing will be referenced in ISO 1101 and ISO 16792, and for NAS 9300 the same
information will be referenced in ASME Y14.5M and Y 14.41). The document formatting etc, will follow
that of the respective editorial rules of ASD-Stan and AIA.
1 Scope
1.1 Introduction
This European Standard defines common fundamental concepts for Long Term Archiving and Retrieval
of CAD mechanical information for elementary parts and assemblies. It details the “fundamentals and
concepts” of EN 9300-003 in the specific context of Long Term Archiving of CAD mechanical models.
CAD mechanical information is divided into assembly structure and geometrical information, both
including explicit and implicit geometrical representation, Geometric Dimensioning and Tolerancing
with Form Features.
The EN 9300-1XX family is organized as a sequence of parts, each building on the previous in a
consistent way, each adding a level of complexity in the CAD data model. This includes the detailing of
relationships between the essential information for the different types of CAD information covered by the
EN 9300-1XX family.
As technology matures additional parts will be released in order to support new requirements within
the aerospace community.
1.2 In scope
The present part describes:
— the fundamentals and concepts for Long Term Archiving and Retrieval of CAD 3D mechanical
information;
— the document structure of the EN 9300-1XX family, and the links between all these parts;
— the qualification methods for long term preservation of archived CAD mechanical information;
more specially, principles for the CAD validation properties and for verification of the quality of the
CAD archived file;
— specifications for the preservation planning of archived CAD information;
— specific functions for administration and monitoring of CAD archived mechanical models;
— the definition of Archive Information Packages for CAD data.
1.3 Out of Scope
The following are out of scope for this part:
— Long Term Archiving of CAD 2D drawings;
— other CAD business disciplines, such as piping, tubing, electrical harnesses, composite, sheet metal
design, kinematics.
This version does not include:
— fundamental and concepts for parts EN 9300-120 version 2, EN 9300-125, 1 EN 9300-130.
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.
EN 9300 (all parts), Aerospace series — LOTAR — LOng Term Archiving and Retrieval of digital technical
product documentation such as 3D, CAD and PDM data
ISO 10303-203:2011, Industrial automation systems and integration — Product data representation and
exchange — Part 203: Application protocol: Configuration controlled 3D design of mechanical parts and
assemblies
ISO 10303-214:2010, Industrial automation systems and integration — Product data representation and
exchange — Part 214: Application protocol: Core data for automotive mechanical design processes
ISO 10303-239:2005, Industrial automation systems and integration — Product data representation and
exchange — Part 239: Application protocol: Product life cycle support
ISO 16792:2006, Technical product documentation — Digital product definition data practices
ISO 1101:2004, Geometrical product specifications (GPS) — Geometrical tolerancing — Tolerances of
form, orientation, location and run-out
3 Terms, definitions and abbreviations
For the purposes of this document, the terms, definitions and abbreviations given in EN 9300-007 and
the following apply.
In addition EN 9300-100 offers further definitions of common terms as following.
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
3.1
CAD 3D mechanical
3D Mechanic CAD covers the definition of the physical shape of a component, the positioning of
components within an assembly, and the information about shape - such as tolerances or surface finish -
which constrains the results of a manufacturing process, but does not specify the process itself. It may
include a record of the geometrical operations, such as trimming a surface, which allow the shape to be
subsequently edited, but excludes parametric design, in which shapes are generated using specific
knowledge embedded in the CAD software
3.2
CAD 3D geometry
the representation of the geometric aspects of the part or assembly, using concepts such as point, line,
cube, etc.
Note 1 to entry: For more information: see Annex B.
3.3
CAD 3D topology
although some classes of CAD modeller explicitly represent volumes (e.g. Constructive Solid Geometry),
many represent volumes indirectly by representing only their surfaces or, in the case of wire frame
modellers, only the edges. CAD 3D topology covers the system of relationships needed to interpret a
collection of lower dimensional geometric elements as a 3D volume
Note 1 to entry: For more information: see Annex B.
3.4
“explicit” representation of a CAD model
in the context of engineering and 3D geometrical the term 'explicit representation' refers to the
mathematical representation of the final result of the CAD model., From the designer's point of view, it
corresponds to the 3D shape (points, curves, surfaces, solids), together with Geometric Dimensions and
Tolerancing
Note 1 to entry: Explicit 3D shape may be associated with non-geometric data including design management
meta-data such as layer, colour or group or user defined properties. These non-geometric data are optional, and
are added by users and checked and validated by specific tools.
3.5
“implicit” representation of a CAD model
CAD model uses an implicit representation if its geometrical representation is based on a
parameterization (e.g. 2D parametric sketches, 3D parametric features such as extrusions of 2D
sketches, holes, pockets), together with a set of operations (e.g. extrusion, revolution) or constraints
(e.g. perpendicularity, parallelism)
Note 1 to entry: The result of the processing of an implicit representation is a CAD 3D explicit representation,
which can be used then for geometric operations such as measurement or clash detection.
3.6
3D Geometric Dimensioning & Tolerancing
symbolic language used on engineering drawings and computer generated three-dimensional solid
models (CAD) for explicitly describing the nominal geometry and its allowable variation. This includes
the nominal geometry of parts and assemblies, the allowable variation in form and possible size of
individual features, and the allowable variation between features
Note 1 to entry: For archiving, GD&T information is a set of information types which are in direct relationship to
each other. The set of information types includes:
— 3D geometry;
— 3D geometric dimensioning;
— 3D geometric tolerances.
Note 2 to entry: Dimensioning information is required to define the characteristics of the 3D explicit model, e.g.
in terms of length or height. This additional information may be linked to one geometrical characteristic, e.g. the
length of a line.
Note 3 to entry: No design geometrical feature can be manufactured to perfection, so the feature description
can be extended with tolerance information. Tolerances may come in the form of limits of size applied to given
dimensions, with ± style tolerance applied directly to dimensions or constraints, such as flatness or parallelism, or
a general note.
3.7
Geometrical Product Specifications
GPS
equivalent to GD&T and PMI (Product Manufacturing Information)
3.8
3D notes
represent additional information, usually a text field, which has no geometric constraint or relationship
to the 3D explicit model, unlike the GD&T information; the positioning of 3D annotation in the 3D
environment of the CAD System is therefore a matter of how best to present the information to the user
The following figure shows an example of 3D annotation:

Figure 1 — 3D annotation
3.9
3D annotations
represent Dimension(s), tolerance(s), note(s), text or symbol(s) visible without any manual or external
manipulation (see ISO 16792, 3.1)
3.10
types of information: “representation” versus “presentation”
3D representation of a CAD model is a mathematical formulation of a geometric shape; the presentation
of that formula for a geometric display requires that the representation is rendered by the
corresponding shape; the process of rendering requires additional presentation information, such as
colour or transparency
Note 1 to entry: For example, a curve may be displayed as a set of pixels of a particular colour in a computer
screen. For example, 3D Geometric Dimensioning and Tolerancing may be presented as a set of 3D polylines,
however, if the GD&T information is represented only by polylines, the human may visualize and understand it as
a GD&T, but the computer is not able to interpret it as GD&T, that is, it is not able to check its consistency with the
3G geometry.
Note 2 to entry: For a single concept, such as Geometric Dimensioning, there may be several representations of
different levels of complexity, and enabling different capabilities. For example, a 3D Geometric Dimension can be
represented as a set of specific objects with precise semantics, enabling automated update or consistency
checking with the related 3D geometry shape subsets. (e.g., distance between two parallel faces).
4 Applicability
Refer to applicability of EN 9300-001, clause 4.
5 Fundamentals and concepts for Long Term Archiving of CAD 3D mechanical
information
5.1 Introduction
The family of EN 9300-1xx standards is based on the principles that, over the last 30 years, there have
been major changes between the generations of CAD applications, resulting in change of the underlying
representation of the CAD information, and there is a risk of further representational changes. Figure 2
illustrates this.
NOTE Figure 2 illustrates:
— The first generation of CAD design method was either to create a 2D drawing (without a 3D model), or to
create CAD 3D model as support for the generation of a CAD 2D drawing. The essential information of the
design intent is represented in a 2D drawing.
— The second generation of CAD design method is based on the complementary use of essential information
defined in 3D models and essential information defined in 2D models (drawings).
— The third generation of CAD design method is based on the use of essential information defined only in 3D
models that contain associative GD&T and annotation to effectively replace the need for a 2D representation.
For more details, see:
— Annex A: evolution of CAD Systems (historical view);
— Annex B: overview of the main types of CAD 3D mechanical information;
— Annex C: overview of the main CAD mechanical assembly structure information;
— Annex E: considerations for long term preservation of CAD 3D information.
Figure 2 — Illustration of the major generations of CAD systems
Some algorithms within CAD applications used in the aerospace industry are proprietary and are not
available to the public. These algorithms represent a competitive advantage to the CAD Company. This
results in the fact that aerospace manufacturers cannot guarantee the access to all essential design
intent in its native format, over the life of the product.
The EN 9300-100 describes the methods for preserving CAD mechanical essential information over
time, recognising that the mathematical representation may change between creation of the CAD
information to its retrieval and hence after importation, the archived file has to be qualified as
acceptable to a level of precision requested by the business function.
5.2 CAD essential information: dependencies on the CAD methods used
Manufacturers may use different CAD methods for the definition of 3D components. The definition of a
part may be based on:
— 2D drawing only, fully dimensioned and toleranced, derived from a CAD 3D exact model;
— 2D drawing partially dimensioned and toleranced, derived from a CAD 3D exact model;
— 3D with GD&T, fully dimensioned and toleranced;
— 3D with GD&T, partially dimensioned and toleranced.
The next Figure sums up the type of CAD information to archive, showing:
— the type of CAD method used;
— the type of use cases for retrieval.
Figure 3 — Type of CAD essential information to archive, depending on the CAD methods used
If a company uses method 1 for mechanical design, this company may decide to archive the CAD 3D
model to ease the reuse, but it is not mandatory and depends of its internal policy. If a company uses
method 2 for mechanical design, Long Term Archiving and Retrieval of 3D CAD models is required; if a
company uses method 3, Long Term Archiving and Retrieval of 3D CAD with GD&T models is required.
5.3 Dependency of CAD essential information on use case
Following the regular enhancements of CAD applications, designers create new types of CAD
information (see Annex A “Evolution of CAD systems”). This standard for Long Term Archiving and
Retrieval of CAD information cannot be defined and implemented in the abstract, but it must be related
to specific business requirements (see EN 9300-002 Clause 6 “Key requirements”) detailed by Use
Cases (see EN 9300-003, Figure 8: Distinction of Business requirements, Business Cases and Use Cases).
These use cases describe precisely the functions to be supported by the preserved information after
retrieval. Consequently they identify the essential information for archive specific to the use case, and
the related mechanisms to validate the full process of preservation. This is illustrated by Figure 4 below.
Figure 4 — Links between Use Cases, essential information and EN 9300 1xx parts
In this example, the part 1XX describes specifications for long term archiving of a set of essential
information N°1, allowing to support retrieval for use cases 1 and 2. Then, the part 1YY describes
specifications for long term archiving of a set of essential information N°2, including the set of essential
information N°1, then supporting additional use cases 3 and 4. The Figure points out also that both the
functions to be supported after retrieval and the associated levels of quality depend of the policy of risk
management of the aerospace manufacturer (see 5.5).
5.4 Use cases shared by different aerospace communities
Aerospace manufacturers share some common requirements, such as certification and product liability,
these result in common use cases for retrieval. However, there are also strong differences in products
and processes between aerospace manufacturers, depending on:
— the type of product (satellites, large civil airframe manufacturer, engines etc.);
— the type of customers (civil, defence);
— the related processes of support.
As a result, the aerospace community does not share a single set of use cases. Some use cases are
common only to a particular community of aerospace manufacturers, which may share the same legal
constraints or business needs. Use cases specific to a company are not described; these may be related
to a particular process, or part of a competitive advantage. Figure 5 illustrates the families of use case.
Figure 5 — Different levels of commonality of business requirements and use cases
The EN 9300-1xx standards describe requirements and use cases for long term archiving and retrieval
of CAD mechanical information which are:
— common to all the community of aerospace manufacturers;
— common to a particular but broad community of aerospace manufacturers, with a scope clearly
mentioned, and with the agreement of the aerospace community.
Some requirements are not shared by all the aerospace manufacturers.
Where a use case is shared by a particular community of aerospace manufacturers, the EN 9300
standard may be extended to include this case.
In the case of uses cases particular to a manufacturer, this manufacturer shall apply the fundamental
concepts of the EN 9300 standards relevant to its needs, and document the related process chain and
essential information.
The next table provides examples of the types of common business requirements and associated use
cases to be shared within a particular aerospace community. Use cases for retrieval of CAD archived
information for “support in operation” may only be particular to a community of aerospace
manufacturers.
Table 1 — Types of business requirements and use cases to be shared within a particular
aerospace community
Types of business requirements
Certification Product Support in Reuse
Liability operation
common to all the
Yes Yes Partially Partially
community of aerospace
Requirements
manufacturers
and use cases
Specific to a community
for Long Term
Yes Yes
of aerospace
Archiving and
manufacturers
Retrieval
Specific to an aerospace
Possible Possible
manufacturer
The section “business specification” of each specific part details the business requirements and the
associated use cases.
5.5 Long Term Archiving and Retrieval of CAD as part of the company risk management
The use of CAD 3D mechanical information results in new risks for long term archiving, quite different
from those encountered in the past for 2D drawings.
The EN 9300 standard defines rules and principles to be applied by the manufacturers. It defines, where
possible, a mandatory a set of verification rules for the CAD model, based on an open international
format, and it defines also validation properties to be created during the ingestion and to be checked
during the retrieval process (see EN 9300-005).
For CAD information, these verification and validation rules are in most cases based on thresholds, the
values of which are not fixed in the standard, since the results are subject to numerical errors in the
algorithms of the CAD applications. The EN 9300-100 standard identifies the point where it may be
adapted by each manufacturer, according to its own specific processes and products. It is the
responsibility of the manufacturer to document and apply the principles, with the appropriate
thresholds, according to an analysis based on risk management, as illustrated in Figure 6.
Figure 6 — Long term preservation of CAD and risk management
The company shall describe precisely the list of rules it has selected for verification and validation
(mandatory and optional), with the associated tolerance thresholds. Then, the company shall archive
the CAD STEP file with the associated validation report and verification report.
The aerospace manufacturer should define a risk management policy to ensure the Long Term
Archiving and Retrieval of CAD information. To reduce the risk, the company should select or establish
an appropriate qualification method.
For more details, see Clause 7: “Qualification methods for long term preservation of CAD archived
information”.
5.6 CAD reference model for Long Term Archiving of Design intent
Once the CAD model has been released, there are three main strategies to preserve the essential
information of the design through the product life cycle:
— Solution 1: to migrate the design intent of the released native CAD format from system X to the
native format of the next generation of CAD system Y, with a process demonstrating that the
essential information of the migrated model is equivalent to that of the original native essential
information.
NOTE This solution is out of the scope of EN 9300, and is not recommended for aerospace products, where
data life is expected to exceed 50 years.
— Solution 2: to convert the released original native CAD model to an archived open format, then to
convert it at retrieval to the target CAD native format, and to ensure that the target native essential
information is equivalent to the original released essential information.
— Solution 3: to convert the released original native CAD model to an archived open format; and in
parallel, to migrate the released native CAD format to the native format of the next generation of
CAD system. The essential information of the archived open format is compared to the essential
information of the migrated native CAD model.
This is illustrated in Figure 7 below.

Figure 7 — Migration strategies
There is a need to identify what is the CAD reference information over the time and corresponding to
the use cases of the organization.
The qualification of a CAD model as the reference is related to its precise purpose within a well-defined
context, relative to the specific processes and methods of each company. According to its specific
processes and uses cases, the company shall decide if the archived CAD model is the reference, or if the
reference is the CAD native model (initially released, or migrated, or converted from the STEP archive).
NOTE For example, the CAD 3D reference model may be used to confirm that the manufactured part
conforms to the design.
The identification of the use cases where the neutral archived CAD model is the reference allows the
company to list the essential information required for the archive. Refer to the relevant appendices of
the specific parts EN 9300-1XX.
5.7 Long Term Archiving of CAD and the maturity of related technologies
The availability of COTS applications able to support open standards for the Long Term Archiving of
CAD - as stipulated in EN 9300-003 - requires the availability of:
— ISO or equivalent open standard defining the CAD information model (e.g., ISO 10303-203 or
ISO 10303-214);
— associated recommended practises, such as that developed and maintained by STEP associations
like the CAX Implementor Forum;
— applications for Long Term Archiving of CAD essential information (for example, STEP interfaces
for CAD systems, STEP file checker, STEP viewer). These applications are developed and
maintained by CAD IT vendors or companies specialised in CAD interoperability solutions;
— qualification of these applications for long term archiving.
The breakdown of EN 9300-1XX family takes into accounts both the priorities of aerospace
manufacturers business needs and the maturity of the related components. The EN 9300 standard
cannot make use of specifications which are immature or do not reflect the consensus of the aerospace
community.
See Annex G: “Overview of maturity of the main components for Long Term Archiving of CAD
mechanical information”.
5.8 Archiving of several files for the same CAD model
The same native CAD model may contain different types of essential information, corresponding to
different use cases. In addition, technologies to archive the different types of essential information are
being developed progressively, and some of them are not yet available. As a result, the organization may
decide to convert the same native CAD model into several neutral archive files, corresponding to
different use cases, and different types of essential information to be preserved.
NOTE The Part 100 allow that the CAD parametric and the explicit information be archived in the same file if
all the appropriate information is preserved.
6 Document structure of EN 9300-1XX family
6.1 Introduction
The family of parts 1XX has been structured based on the main types of CAD essential information
required for each archive use case, taken into account the technologies available.
As described in EN 9300-001, the structure of parts for the EN 9300-1xx part family is shown in
Table 2:
Table 2 — Document structure of EN 9300-1XX family
9300-100 Common concepts for LT Archiving of CAD 3D mechanical information
9300-110 LOng Term Archiving of CAD 3D Explicit Geometry
9300-115 LOng Term Archiving of CAD Explicit Assembly Structure
LOng Term Archiving of CAD 3D Explicit Geometry with Geometric Dimensioning &
9300-120
Tolerancing associated with Form Features
LOng Term Archiving of CAD Explicit Assembly Structure with 3D Geometric
9300-125
Dimensioning & Tolerance associated with Form Features.
LOng Term Archiving of CAD 3D parametric geometry with Geometric Dimensioning &
9300-130
Tolerance
LOng Term Archiving of CAD parametric Assembly Structure with 3D Geometric
9300-135
Dimensioning & Tolerance associated with Form Features
For clarity and consistency, the document structure of each specific part of the EN 9300-1xx family will
follow the same structure, as described in Annex D: Template of the structure of a part of the family
EN 9300-1xx.
6.2 Link with other EN 9300 parts
6.2.1 Link between parts EN 9300-1XX for fundamental and concepts
To share common concepts across several EN 9300 parts in a consistent way and without duplication,
the generic concepts for long term archiving and retrieval of all types of 3D design aerospace
information are described in EN 9300-003. Part EN 9300-100 describes all concepts common to the
family EN 9300-1XX. Each part 110, 115, 120, etc. will detail the concepts specific to its scope. This is
illustrated in the figure below.

Figure 8 — Detail level of EN 9300 part related to description of fundamentals & concept
6.2.2 Relationship/linking between the EN 9300- 1xx family
The EN 9300-120 will reuse the principles of LT Archiving of the essential information described in
EN 9300-110.
The EN 9300-125 will reuse the principles of LT Archiving of the essential information described in
EN 9300-115 and EN 9300-120.
The EN 9300-135 will reuse the principles of LT Archiving of the essential information described in
EN 9300-130.
Since the EN 9300-1xx parts are linked among each other at more than just the level of detail, it is
necessary to comment on the relationships linking the parts and their constraints. In general it is
possible to add different kinds of information into one Archival Information Package (AIP). This
includes, for example, native formatted files as well as archived formatted files. As a further breakdown,
it is possible to add different kinds of information into one archived formatted file. This means that one
STEP files can contain relevant information from different Data Domain Specific Parts. The following
Figure shows an example:
Figure 9 — Relationship / linking between the EN 9300-1xx Family
The archived STEP file contains different kinds of information. In this example verification and
validation properties for 3D shape information, auxiliary geometrical/layer information and GD&T
information were archived. Although the AIP contains all kinds of information, the description of
requirements/definitions for these kinds of information belongs not to one EN 9300 part but to
different parts. This leads into following conclusion:
For the specific use case of archiving explicit 3D geometrical information, only EN 9300-110 is in scope.
If the AIP contains additional information, then every relevant Part of the EN 9300-1xx family should be
considered.
See also Annex: “Essential information for long term archiving of CAD”.
7 Qualification methods for long term preservation of archived CAD information
7.1 Introduction
As stated in Clause 5, Long Term Archiving and Retrieval of CAD mechanical information is based on the
precise identification of the essential information, according to a specific context described by a set of
Use Cases. Historically, each new generation of CAD application has had an associated change of
mathematical representation of the CAD information. Since further change cannot be ruled out, the CAD
information may have to be transformed to a new representation during the import into the target CAD
system, with a consequent risk of uncontrolled change to the essential CAD information.
The long term archiving and retrieval process described by the parts EN 9300-010 to EN 9300-015
describes a chain of several data format conversions (from native source CAD format to STEP format,
then from STEP format to native target format) each of which has a risk that the CAD information may
be altered.
The company shall therefore ensure the long term preservation of the archived CAD information by the
control of the essential information as identified in the Parts of the family EN 9300-1XX, and by
monitoring changes to all components involved in the associated archival process chain.
Qualification methods should
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