LOTAR Standard

Terms and Definitions

This web page lists the terms and definitions given in EN/NAS 9300-007. This list is being updated constantly with input from the various LOTAR workgroups, and on a regular basis, the consolidated list will be published in a new edition of LOTAR Part 007. For each term or definition, the earliest edition of Part 007 it is listed in is stated. If the publication status is given as “Web”, the entry can currently be found only here, and will be included in the next edition of Part 007.

All - 3 - A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W

Status Term Definition
Web 3D Annotation text, notes, flag notes, dimensions, tolerances, or GD&T that is modeled in 3D space with leaders pointing to the solid model features.
Ed.3 3D Model Based Definition - Model Based Definition (MBD) is a set of concepts, processes, and tools that allow the creation of an annotated 3D product definition based on a 3D solid model. The MBD dataset includes all Engineering Intent requirements (including Process Specifications, Geometric Dimensioning and Tolerancing (GD&T), Product and Manufacturing Information (PMI), and other required information). Combined with product lifecycle management (PLM) attributes, a parts list, and general notes, this constitutes an authoritative, single source of master product definition data that does not include or depend upon traditional 2D drawings. The MBD dataset defines complete requirements for a product in its nominal condition as well as permissible limits of variation and other acceptance criteria, providing all the data needed to plan, fabricate, and validate an article of product hardware.
Status Term Definition
Ed.3 Access from the OAIS model, the process of recovering data from the archive.
Web Adhesive a substance used to bind two or more other components together via surface contact. The adhesive can be a film, paste or liquid.
Ed.3 Administration (OAIS cf also NAS9300-13 7.3) the management of the archive and its daily operation.
Ed.3 Administrator (OAIS cf also NAS9300-13 8.1.3) the organization or person responsible for management of the archive and its daily operation.
Web Advanced Composite Structure a hybrid structure in which composite laminates of materials with high strength and stiffness with a resin matrix (thermoset or thermoplastic) are used in combination with other components (like core, fiber optics, active electronics, passive electronics, metal, ...) in order to create a multi-functional design.
Web Allowable the material strength, strain or load which can be used as a basis for generating a margin of safety from.
Web Anisotropic exhibiting different properties along axes in different directions.
Ed.3 Application Activity Model (AAM) from STEP, the model of activities that defines the context for a particular Application Protocol.
Ed.3 Application Interpreted Model (AIM) one of the STEP information models, historically used as the basis for implementation.
Ed.3 Application Protocol (AP) from STEP, one of the major parts of the standard that provides an implementable data exchange in a particular context.
Ed.3 Application Reference Model (ARM) from STEP, an information model that describes the information requirements and constraints of a specific application context.
Ed.3 Archival Information Package(AIP) (OAIS) An Information Package, consisting of the Content Information and the associated Preservation Description Information (PDI), which is preserved within an OAIS. (Note - this is the package actually retained by the archive, containing both the Content Information and all necessary PDI's.)
Ed.3 Archival Storage (OAIS, cf also NAS9300-10 6.3 and NAS9300-13) The process includes the setting of digital time signatures, generation of additional Descriptive Information for Archive Information Packages (meta data for the archive) and the physical storage of the data within the archive.
Ed.3 Archive (1) A repository for historical information.
Ed.3 Archive (2) Any repository conforming to the OAIS standard. (OAIS, cf also NAS9300-10 7.1.1) The Archive is the archiving environment, which usual supports at least the key functions of an archiving architecture according ISO 14721 (OAIS). Note: This is the preferred sense in the LOTAR documentation.
Ed.3 Article see Product, Part, Item and Article.
Web As Fabricated a representation of a part as it is made by the Prime or a supplier.
Web As Installed a representation of a part which shows how the part is deformed from its "As Fabricated" configuration when it is installed in an assembly.
Ed.3 Audit Trail Information collected during the execution of a process that shows what actually occurred.
Ed.3 Authentication (1) Ensuring something is what it purports to be.
Ed.3 Authentication (2) In security, ensuring the claims to identity of one party are proven to the satisfaction of another.
Web Autoclave a sealed containment vessel used to induce a chemical reaction under heat and pressure.
Web Automated Fiber Placement (AFP) The process by which a machine lays multiple courses of narrow tows on a form.
Web Automated Tape Laying or Lamination (ATL) The process by which a machine lays a series of single, wide tapes on a form.
Status Term Definition
Web Bag Side the side of a composite part next to the vacuum bag during the cure cycle. Thickness variation is pushed to this side of the laminate and away from the tool side.
Web Band is the grouping of tows that a fiber placement machine puts down on a lay-up surface at any one time. Note - the width of a band can be made wider or narrower during a single pass by adding or eliminating tows. Also - see Course
Web Bond Assembly a part made up of composites and other components like core, fiber optics, active and passive electronics, other systems and procured details that are bonded together to generate a detailed part.
Web Bridging a condition where plies span a chamfer or radius without generating full contact. Bridging can be reduced with male tooling, larger radius tooling and pressure intensifiers.
Web Broad goods typically wide prepreg material (fabric or unidirectional) in roll format
Ed.3 Business Application (cf NAS9300-003, 3.2.3) - the software creating and generating native Product Models.
Status Term Definition
Web Carbon Fiber high strength fiber used in advanced composite designs
Web Caul Plate secondary tooling on the bag side used to provide a smooth and controlled surface.
Ed.3 Certification (1) the process of assessing a process or product against some particular set of criteria.
Ed.3 Certification (2) the particular process of certifying an aircraft type as being airworthy. Note: For clarity, LOTAR uses the term "Type Certification" in this context.
Ed.3 Character-based Presentation is a type of Presentation where the conveyed information is stored as characters (letters, numbers, and symbols). These characters are typically stored in a string variable that can be retrieved and edited in a consuming application. The appearance of Character-based Presentation depends on the font being used and may change if the originating system and the consuming application use different fonts. To ensure no characters are lost from creation to consumption, the alphabet (character encoding) used must be defined as well.
Example - In ASCII, the letter 'A' is stored as character code '0x41' (hexadecimal).
Character-based Presentation is often supplemented by geometric elements, such as leader lines, curves or terminator symbols.
Web Co-Bond joining together cured composites and other non-composite components (metal, systems, etc) to an uncured composite lay-up.
Web Co-Cured simultaneously bonded and curing assemblies of uncured composite details to one another.
Web Composite a material created from a fiber (or reinforcement) and a matrix material in order to maximize specific properties. The constituents do not merge - but retain their identities as they act in concert
Web Composite Inseparable Assembly (aka pre-cured) is a design that contains the geometric definition of all of the composite plies along with the relative location and stacking of any additional components. At a minimum the plies will be defined by geometry, material and an orientation with a related rosette. In addition, there can be core, pre- and co-cured definitions, stitching, pinning, systems, impact strips and other embedded components.
Web Composite Materials two or more materials that are combined to form a useful engineering material that has properties not found in the constituents which retain their identities in the composite process.
Web Composite Part (aka structural part) is a definition that contains a solid representation of the cured part including holes, cutouts, chamfers surface treatments, and Limited Area Application Indicators or LAAIs. It uses the typical dimensioning practices with GD&T and PMI and is specified with a non-homogenous material property. Basically, it should be defined using information found in the NAS 9300-210 documentation. A best practice would be to create it as a separate dataset with a "Make From" note referencing the related Composite Inseparable Assembly - but, not containing any information about the plies, components or materials that make it up.
Ed.3 Configuration Management (1) the discipline of managing the information relating to a product design, encompassing change management, configuration identification, status accounting and audit. Note: this is the preferred sense in the aircraft industry, and in the NAS9300 documentation.
Ed.3 Configuration Management (2) the rules relating to the choice and combinations of options used when configuring a particular physical example of a product.
Ed.3 Consumer from OAIS, the user of data taken from an archive. (OAIS, cf also NAS9300-10 7.1.2) The consumer is an organization, person, or client system, which interact with the services offered by the archive to find preserved information of interest and to access that information in detail. (See also Designated Community)
Ed.3 Content Information (OAIS) The set of information that is the original target of preservation. It is an Information Object comprised of its Content Data Object and its Representation Information. An example of Content Information could be a single table of numbers representing, and understandable as, temperatures, but excluding the documentation that would explain its history and origin, how it relates to other observations, etc.
Ed.3 Context Information (OAIS) The information .that documents the relationships of the Content Information to its environment. This includes why the Content Information was created and how it relates to other Content Information objects.
Web Core (Honeycomb) a lightweight cellular structure formed into hexagonal, nested cells (like a beehive) that is used in composite sandwich constructions. The material may either metal on non-metallic.
Ed.3 Core Model (NAS9300-003, the essential minimum of data which are required to preserve the design intent for a given purpose.
Web Core Ribbon Direction an indicator that shows the direction of maximum shear strength and rigidity along the continuous webs of material.
Web Course a course consists of a head path and all the tows which are laid as a machine's head traverses the path. Also - see Band
Web Cross-linking an irreversible bonding of polymer chains that restricts movements between the chains and results in significant changes to the mechanical properties.
Web Crossply plies definitions in which different layers have orientations that cross each other - for example a 0/90 layup.
Web Cure to irreversibly change the properties of the binding resin in a composite layup.
Web Cured Ply Thickness (CPT) the thickness of a ply after it has been cured and typically less than the uncured thickness.
Ed.3 Cyclic Redundancy Check a method for checking the integrity of a set of digital data
Status Term Definition
Web Dart a wedge of material cut out of a ply in order to facilitate laydown without stretching or wrinkling.
Ed.3 Data (ISO 10303-1) a representation of information in a formal manner suitable for communication, interpretation, or processing by human beings or computers.
Ed.3 Data Object a collection of data treated as a single unit, such as a CAD model or file
Ed.3 Data Preparation (NAS9300-10 6.1 and NAS9300-11) the data to be archived will be prepared by the producer. This includes data verification.
Ed.3 Data Selection (NAS9300-14 6.3) the functions to search the archive for data.
Ed.3 Dated or Undated Reference a reference to a version controlled document. In a dated reference, the particular version is identified by its date of issue. In an undated reference, the particular version is the latest released version.
Web Delamination the post cure separation of plies in a laminate causing reduced mechanical properties.
Ed.3 Description Method a (usually formal) method of describing information and its structure
Ed.3 Descriptive Information (DI) (OAIS) The set of information, consisting primarily of Package Descriptions, which is provided to Data Management to support the finding, ordering, and retrieving of OAIS information holdings by Consumers.
(OAIS) - The Information Package, derived from one or more AIPs, received by the Consumer in response to a request to the OAIS.
Ed.3 Designated Community from OAIS, the community for which the system is designed. In the case of NAS9300, it is the community that will use the information retained in an archive.
Ed.3 Digital Signature see Electronic Signature.
Ed.3 Disaster Recovery the recovery of the archive in the event of major failure or destruction of the archive.
Ed.3 Document this term covers a family of usages, from a physical paper document, through electronic files which can be thought as representing a document, to synthetic view derived from multiple sources for which the user's conceptual model is that of reading a document. See also NAS9300-003 5.3.1 "Archiving Product Models vs. Archiving Documents"
Ed.3 Domain Specific Part LOTAR parts are either general or domain specific. LOTAR parts 100 upwards are the domain specific parts, and deal with the particularities of each type of data such as 3D CAD. The general parts (1 to 99) apply to all types of data.
Web Draping Direction the direction perpendicular to the ply definition surface defining the direction in which the layers of plies will be stacked up.
Status Term Definition
Web EEOP - Engineering Edge Of Part supplemental geometry represented in the dataset that defines the engineering defined periphery of the part. See EOP. (This is in the STEP stds as well as Fibercim.)
Ed.3 EXPRESS from STEP, a formal data modeling language, defined in ISO 10303-11.
Ed.3 EXPRESS-G from STEP, a diagrammatic form of EXPRESS.
Web Edgeband laminate areas on a honeycomb sandwich part that are outside the edge of the core definition.
Ed.3 Electronic Signature a defined method to sign an object in electronic environments. It provides means to authenticate the signatory and the signed object in an unambiguous and safe way by attaching to or logically associating data in electronic form to other electronic objects. (See NAS9300-005)
Ed.3 Engineering signature (NAS9300-005) a digital signature with which the data producer asserts that the prepared data fits with the process and quality requirements from the engineering point of view.
Note: The terminology of part 5 clarifies the term "Digital (engineering) signature" from NAS9300-003,
Ed.3 Essential Information the information that must be preserved, as relating to the key characteristics (qv) of some aircraft component.
Ed.3 Evidential Weight from Code of Practice for Legal Admissibility, in the case where electronic information is used as evidence in a court case, the degree of reliance that the information is what it purports to be.
Ed.3 Explicit (as in explicit geometry) where each geometric element is defined in terms of the space it exists in, e.g. a line is defined by its end points. In parametric geometry, the elements are defined through a construction procedure, so that if the parameters change, the element itself changes - e.g. a line is defined as being the normal to a face from its center. Note, an explicit geometric element may be constructed manually by some procedure, but subsequent changes to the starting entities of the procedure do not change the element.
Web Explicit (with regards to composite ply representation) where each ply element is defined in terms of the space it exists in, e.g. a ply is defined by its 3D shape representation. Note, an explicit ply element may be constructed by using the implicit representation of the ply and certain parameters (e.g. thickness etc.), and the composite mechanism used to produce it.
Ed.3 Extensible Mark-up Language (XML) a mark-up language, used to identify fields within a file that can be processed by a Web Browser. STEP provides an XML binding for AP's
Status Term Definition
Web Fabric material constructed of woven fibers (aka cloth)
Web Face Sheets the laminate skins surrounding the core material in sandwich construction.
Web Fiber a homogeneous strand of material used as the main load carrying component of advanced composites.
Web Fiber Content is the percentage of fiber found in a composite part defined by weight or volume.
Web Fiber Orientation the relative alignment of the fibers in a composite ply to the definition Rosette assigned to that that ply. (Aka Fiber Direction)
Web Filament a single strand of fiber. Thousands are bundled together to create a Tow.
Ed.3 File A named collection of data managed as a single unit at the level of a computer operating system
Web Filler Ply plies that are not required for mechanical properties - but, are added for some other manufacturing or assembly related requirement.
Ed.3 First Article Inspection The organization's system shall provide a process for the inspection, verification, and documentation of a representative item from the first production run of a new part, or following any subsequent change that invalidates the previous first article inspection result. (Source Boeing)
Ed.3 Fixity Information ancillary information that show a particular set of information is unchanged.
Ed.3 Fixity Information (OAIS) The information which documents the authentication mechanisms and provides authentication keys to ensure that the Content Information object has not been altered in an undocumented manner
Web Flat Pattern the 2-Dimensional shape of a 3D contoured part whose boundary curve lengths are the same as the part in its formed shape.
Status Term Definition
Ed.3 Geometric Dimensioning and Tolerancing (GD&T) the definition of the physical dimensions of a component and the allowable variation on those dimensions.
Ed.3 Graphic Presentation is a type of Presentation where the conveyed information is converted to geometric elements (lines, arcs, surfaces) by the source system in a way that preserves the exact appearance (color, shape, positioning) of the presented information. The arrangement of these geometric elements can be interpreted by a competent human by looking at them, while the information content is no longer directly computer-accessible.
Example - A simple graphic presentation of the letter 'A' is given by three straight lines. A more complex graphic presentation could have ten straight lines and six circular arcs, but would still be recognizable as an 'A' to a human familiar with the Latin alphabet. In both cases, a computer can only access the geometric definition of the individual elements (start and end coordinates for each line), but not the fact that it is the letter 'A' that is being presented.
Graphic Presentation does not require defining the font or alphabet (character encoding) originally used in the creation of the presented data. In the way Graphic Presentation data is stored, there is typically no distinction between geometric elements that are visual representations of characters, and geometric elements that are visual representations of other constructs, such as leader lines, curves or terminator symbols.
Note - An indirect way of accessing the information content stored as Graphic Presentation is the application of character recognition software that will attempt to identify the original characters from the geometric elements that make up their visual representation. Character recognition, however, has its limitations depending on the algorithms used, the fonts and alphabet involved, and the granularity of the Graphic Presentation geometry elements. Its results cannot be used with the same level of reliability as Character-based Presentation
Status Term Definition
Web Hand Layup the manual process of applying fabric (usually prepreg) to a layup tool
Ed.3 Hyper Text Mark-up Language (HTML) a mark-up language, used to indicate display parameters within a file that can be processed by a Web Browser.
Status Term Definition
Ed.3 IDEF0 a modeling methodology for describing activities and the relations between them.
Web IML - Inner Mold Line The derived surface generated by the last ply defined in a laminate stack-up
Web ISA - Inner Skin Assembly the derived surface generated by the combination of the last plies defined in a co-cured "skin" assembly type design. Equivalent to the inner skin surface (ISS) plus the IMLs of parts defined and co-cured on the ISS.
Web ISS - Inner Skin Surface the derived surface generated by the last ply in a "skin" part type definition
Web Implicit (with regards to composite ply representation) where each ply element is not explicitly defined in terms of the space it exists in, but can be defined by the contour and the tooling surface. Note, an explicit ply element may be constructed by using the implicit representation of the ply and certain parameters (e.g. thickness etc.), and the composite mechanism used to produce it.
Web Inclusion a discontinuity in a composite part usually composed of encapsulated foreign material.
Ed.3 Information (ISO 10303-1) facts, concepts, or instructions.
Ed.3 Ingest from the OAIS model, the process of transferring data to the archive.
Ed.3 Ingest (2) (OAIS, cf also NAS9300-10 6.2 and NAS9300-12) During the Ingest process the data producer submits the Submission Information Package from the data preparation environment into the archiving environment.
Web Insert a separate part made of metal or plastic that is inserted into a composite part, typically where point loads are to be introduced into a sandwich panel
Web Interlaminar related to the interface surface between the plies
Web Isotropic materials that have uniform mechanical properties in all directions
Ed.3 Item see Product, Part, Item and Article.
Status Term Definition
Ed.3 Joint Aviation Requirements (JAR) JAR is the prefix for standards and related documents produced by the Joint Aviation Authorities.
Status Term Definition
Ed.3 Key Characteristic (NAS 9100:2003, which in turn is based on ISO 9001:1994) The features of a material or part whose variation has a significant influence on product fit, performance, service life or manufacturability.
Status Term Definition
Ed.3 LOTAR (1) The generic name for this standard.
Ed.3 LOTAR (2) The name of the project/project team that generated this standard
Web Laminate product made by bonding together two or more plies. Basically, means a composite system made up of layers/plies of fiber reinforcement in a resin without intermediate inserts (like core).
Web Laminate Coordinate Axes see Rosette
Web Laminate Table see Ply Table
Web Laser Projection the visualization of plies and related information based on traces projected from lasers onto a layup tool.
Web Layup the definition of a stack of plies prior to cure
Ed.3 Legal Admissibility from CoP for Legal Admissibility, the rules under which information can be used in support of a legal case.
Web Limited Length or Area Indicators (LLAI) for Composite Product Definition A LLAI may be used to define a specific region of the part with unique characteristics or requirements. Lamina - a single ply of composite material
Ed.3 Long Term long enough for information to be affected by changing technologies, including support for new media and data formats, or a changed user community.
Ed.3 Long Term Archiving (NAS9300-003, 3.2.5) Storage of a copy of data in an appropriate way for record, certification and legal purposes.
* The data will be preserved and kept available for a use within the archive and possibly for further re-use.
* With certified conversion processes, the native data representation generated by the source system can be converted into a representation which is appropriate for long term archiving. To fulfill legal and certification requirements, the stored form can be an accurate or approximate representation of the source.
* Integrity must be ensured by a digital signature
* The data is retained over the long term
* Invariance is mandatory
* Business, legal and certification requirements are covered
Status Term Definition
Web MBD - Model Based Definition is a set of concepts, processes, and tools that allow the creation of an annotated 3D product definition based on a 3D geometric representation. The MBD dataset includes all Engineering Intent requirements (including Process Specifications, Product and Manufacturing Information (PMI), Geometric Dimensioning and Tolerancing (GD&T), and other required information). Combined with product lifecycle management (PLM) attributes, a parts list, and general notes, this constitutes an authoritative, single source of master product definition data that does not include or depend upon traditional 2D drawings. The MBD dataset defines complete requirements for a product in its nominal condition as well as permissible limits of variation and other acceptance criteria, providing all the data needed to plan, fabricate, and validate an article of product hardware.
Web MEOP - Manufacturing Edge Of Part supplemental geometry represented in the dataset that defines the manufacturing periphery of the part which is usually outside the EEOP. The MEOP may include material to account for tooling tabs or handling lugs, or material excess for Producibility of the part, and allows material to be trimmed back to the engineering edge of part (EEOP) prior to or on assembly. - See EOP - See comments on EEOP
Ed.3 Manufacturer a company that makes physical products, although this term is also used to refer to companies that create designs, usually on behalf of the manufacturer. This is more properly called the manufacturing definition supply chain.
Web Matrix content the percentage of matrix found in a composite by volume or weight.
Ed.3 Media the physical material on which data is recorded, such as an optical disc
Ed.3 Metadata (1) data about data. For example, the file name is Meta data about a CAD design held as a file.
Ed.3 Metadata (2) the data required for the management and use of information packages.
Note: This is the preferred sense in the NAS9300 documentation.
Web Minimum Length Tow Fiber Placement machines typically have a head design that heats and applies pressure to the tows that are being placed and includes a set of rollers and knives. The distance between where the pressure is applied and the tows are cut is the minimum length of tow that can be laid and is limiting factor when trying to match ply boundaries with sharp corners - requiring additional or extra material to assure total coverage.
Web Mirrored (Opposite hand) An opposite composite part is geometrically symmetrical including ply geometry, fiber orientation, and finished part trim. If the parts are not completely symmetrical, both parts must be completely defined. The opposite part shall have a mirrored ply orientation symbol.
Status Term Definition
Web NDI - Nondestructive Inspection measuring the condition of a composite part without damaging/degrading the laminate or other components.
Ed.3 Native format the format in which a software application stores its data, where that format is part of the design of the software.
Web Nesting the process of locating the flat patterns produced from plies next to each other on rolls of "broad goods", (Fiber woven to form fabric up to 1270mm), in order to minimize scrap and optimize production rates. Once they are cut from the roll they are usually kitted or grouped together for manufacturing consumption.
Web Noodle See Radius Filler
Status Term Definition
Ed.3 OAIS Model the Open Archival Information System reference model (see normative references).
Web OML - Outer Mold Line Typically, this is a lofted surface representing the initial or definition surface for a composite definition
Ed.3 Open Data Standard is an Open Standard (see "open standard") defining the syntax, semantics and pragmatics of a data model.
Ed.3 Open Standard is a standard that must fulfill the following criteria:
* Described precisely in a way that is widely and freely available and does not use proprietary methods or practices; (e.g., object modeling methods using UML or EXPRESS) and includes defined semantics.
* Format and services implementing the data are explicitly described (e.g., STEP Part 21 or XML, PLM services, binary/text formats, etc.) and documentation of the format and services is readily available.
* The updating process is described and well accepted by the applicable community and all organizations in that community are able to comment and participate in the approval process; (e.g., STEP ISO ballot procedures, OMG and W3C consortium procedures).
* Responsibility for maintaining the standard is clearly defined and held by a responsive organization;
* The standard and its documentation is publicly available, is not restricted by royalties, patents or other Intellectual Property restrictions, except possibly copyright, in which case copies must be available at reasonable cost.
Ed.3 Original Product Model the model used to keep the design intent for Long Term Archiving in the context of certification & legal requirements for proof.
Status Term Definition
Ed.3 PDM Schema the STEP schema for Product Data Management data.
Ed.3 Packaging Information (from OAIS) the information that is used to bind and identify the components of an Information Package. For example, it may be the ISO 9660 volume and directory information used on a CD-ROM to provide the content of several files containing Content Information and Preservation Description Information.
Ed.3 Part see Product, Part, Item and Article.
Ed.3 Part 21 from STEP, one of the ways of implementing STEP, being the default ASCII file encoding.
Ed.3 Platform the particular hardware used in the creation, recording and viewing of electronic
Web Ply one of the components that make up a composite stack or laminate. There can be one or more plies in each layer/step/sequence - but, they should not overlap.
Web Ply Boundary the inner and outer edges of a ply
Web Ply Coordinate Axes see Rosette
Web Ply Definition Surface The base surface engineering uses to define plies on: It is typically equivalent to the tool side surface, but not always. Engineering sequencing and ply stack-up definition begin on this surface.
Web Ply Draping Placement of a ply on the manufacturing tool and previously placed components so that it lays smoothly without wrinkles.
Web Ply Orientation is a reference angle defining the desired rotation of the individual plies fibers relative to the reference coordinate system defined by a Rosette. Typically, orientations are 0 deg, 90 deg, +45 deg and -45 deg. But, they can be any angle between 0 deg and 90 deg.
Web Ply Table (also laminate table) a table of information describing the properties (material, orientation, rosette, process notes) related to each ply. A Laminate table defines the internal constituents or structural makeup of an overall part or a particular zone, area, or point on the part.
Ed.3 Polyline Presentation designates a specific implementation form of Graphic Presentation that is supported by many STEP Application Protocols, including AP203e2 (ISO10303-203:2011), AP214e3 (ISO10303-214:2010) and AP242 (ISO10303-242:2014). It supports all the characteristics of Graphic Presentation. A Polyline is defined as an ordered list of 3D points, which are consecutively connected by straight line segments. Circles and circular are the only other allowed geometric elements, and can be used in combination with Polylines. Filled areas can be defined with the aforementioned elements as boundaries.
Web Potting a paste used to reinforce local areas of core
Web Pre-cured a laminate that has been cured prior to bonding to another laminate or component assembly
Web Preform an insert of "dry" fabric or fibers that have been build up independent of the overall laminate definition. Often used in RTM or SRFI manufacturing processes.
Web Prepreg composite material pre-impregnated with resin in the form of sheets, tape or tow.
Ed.3 Presentation designates a certain way how information is being stored; it does not relate to the information content itself. Presentation defines the visual representation of a character, word, phrase, sentence, paragraph, specification, or symbol in way that is understandable by humans. Presentation is a generic term that applies to any form of human-readable information transfer; this can for instance be a handwritten note, an engineering drawing, or the display of a 3D CAD model on a computer screen. The main purpose of Presentation is to facilitate human comprehension of the data, e.g. to manufacture, inspect, assemble or maintain the product described by the data. For a correct interpretation of the presented data, it is required that the reader is familiar with the alphabet used and the general type of information being presented.
In the context of 3D CAD, the term Presentation relates to elements that are visible in the display of a 3D model and are either located (positioned) in 3D space, i.e. they rotate and move with the model, or in a fixed 2D plane. Elements of Presentation can typically by styled (e.g. colored), organized (e.g. in specific views), and associated with other elements of the model. Presented types of data typically are geometry (3D shapes, surfaces, curves, points) and characters (letters, numbers, symbols etc.).
Ed.3 Preservation Description Information (OAIS) Preservation Description Information (OAIS) - the information which is necessary for adequate preservation of the
Ed.3 Preservation Planning from the OAIS model, the services and functions for monitoring the environment of the OAIS and providing recommendations to ensure that the information stored in the OAIS remains accessible to the Designated User Community over the long term, even if the original computing environment becomes obsolete
Ed.3 Privacy rights relating to the collection, recording, and access to data concerning a particular identifiable individual
Ed.3 Producer from OAIS, the creator of information to be archived
Ed.3 Producer (2) (OAIS cf also NAS9300-10 7.1.3) The producer is an organization, person, or client system, which provides the information to be preserved.
Ed.3 Product & Manufacturing Information (PMI) Product and Manufacturing Information (PMI) is used in 3D Computer-aided Design (CAD) systems to convey information about the definition of a product's components for manufacturing, inspections and sustainment, which supplements the geometric shape of the product. This includes, but is not limited to, data such as dimensions, tolerances, surface finish, weld symbols, material specifications, 3D annotations and user defined attributes. The term PMI, used by itself, relates to certain information content within a product definition; i.e. it indicates what information is being stored, independent from how it is being stored. Though PMI is generally accepted to be the generic designation, the term Geometric Dimensions and Tolerances (GD&T; sometimes also listed as Geometric Dimensioning and Tolerancing) is often used synonymously, as it is the main type of PMI that is currently in focus. Other synonymously used terms are: General Tolerances and Annotations, Annotation, Smart Dimensions, Functional Tolerancing and Annotation (FT&A) or Geometric Product Specification (GPS). Some of these are specific to a particular CAD system. Industry standards for defining PMI include standards such as ASME Y14.5, ASME Y14.41 and ISO 1101, ISO 16792 respectively.
Ed.3 Product (From ISO 10303-1) a thing or substance produced by a natural or artificial process. (See also see "Product, Part, Item and Article" in Terms (3.1 above).
Ed.3 Product Data Management (PDM) the tracking, control and status control of product data, either as files, or through a database. The usage is frequently confined to the design stage of product development, although may extend to planning for manufacture.
Ed.3 Product Information Model (cf NAS9300-003, 3.2.1) the product information model is an information model which provides an abstract description of facts, concepts and instructions about a product, such as a STEP Application reference model or STEP Application interpreted model.
Ed.3 Product Lifecycle Management (PLM) the tracking, control and status control of product data, either as files, or through a database. PLM extends the scope of PDM to include each physical product produced from a design, including deviations from the design and usage of the product.
Ed.3 Product Model (cf NAS9300-003, 3.2.2) The Product model represents an occurrence of an product information model for a particular product, e.g. the geometric model of part a123.
Ed.3 Product data (From ISO 10303-1) a representation of information about a product in a formal manner suitable for communication, interpretation, or processing by human beings or by computers.
Ed.3 Product, Part, Item and Article In general aerospace usage during the design phase, Part, Item and Article are treated as synonyms referring to unitary parts or simple assemblies that are treated as a single unit, such as composite material part or an electrical connector. The term Product tends to be used to refer to something that is complex and deliverable, such as an airplane. In ISO 10303, Product is the general class of any deliverable, from individual components upwards, and allows for the fact that even a simple bolt is the product of a bolt manufacturer. ISO 10303-239 (PLCS) uses Part as a subtype of Product to identify the design of a physically realizable component or assembly, as distinct from other subtypes such as Product_breakdown or Interface. It also uses the term Product_as_realised to distinguish a physical realization of a design from the design itself. That is, the terminology is context sensitive. Since the initial focus of LOTAR was the design phase for the manufacturers of aircraft and aircraft engines, the terminology follows the general aerospace usage.
Ed.3 Provenance the information describing the context in which information was created.
Ed.3 Provenance Information (OAIS) the information that documents the history of the Content Information. This information tells the origin or source of the Content Information, any changes that may have taken place since it was originated, and who has had custody of it since it was originated.
Web Pultrusion the process of producing a continuous composite shape by pulling collated prepreg material through a die.
Status Term Definition
Ed.3 Quality Agent (cf NAS9300-011 8.1.2) a system tool, organization or person which is responsible for completeness, quality and consistency of the data to be retained according a defined list of quality criteria.
Web Quasi-isotropic a laminate that approximates isotropic properties by orienting plies in several directions.
Status Term Definition
Web RTM - Resin Transfer Molding A closed mold process in which dry fabric, tape, perform, or stitched material is placed within a die. The matching die is then clamped in place. Resin is then pumped into the die under pressure and residual air bled out. The die is then heated until the part is cured.
Web Radius Filler Filler material added at the intersection of two or more laminates to smooth the contour or fill a void at the intersection. It may also be added at core edge.
Ed.3 Removal (OAIS, cf also NAS9300-10 6.5 and NAS9300-15) deletion of data or outsourcing of data, for example into a technical museum, which does not meet the requirements of a long term archive.
Ed.3 Repository (1) the physical location where something is stored.
Ed.3 Repository (2) a system that acts as a virtual location where something is stored (i.e. information is submitted to the repository system, which then manages its physical storage)
Ed.3 Representation the way in which a concept is modeled as a system of data element. For example, a point may be reified as a set of three numbers, representing its x, y, and z co-ordinates (cf presentation).
Web Resin Resin is generally a polymer that used to bind together the reinforcing materials (fibers) in a composite.
Ed.3 Retention (NAS9300-003, 3.2.4) Storage of data for reuse at a later date:
* Aiming for data re-use and to keep data available
* Retaining any of the representations needed, but not the presentations
* Working over medium and short term
* Expecting invariance, though this is not mandatory
* Migration of the data format is allowed to guaranty data quality and interpretability.
Ed.3 Retrieval (OAIS cf also NAS9300-10 6.4 and NAS9300-14) Retrieval provides functionality for a data search to select the required data (provided the Consumer is allowed to see it), and the generation of a Dissemination Information Package (DIP).
Ed.3 Risk the product of the probability of an event occurring with a measure of the effects of that event, usually with the connotation that it is adverse effects that are being measured.
Web Rosette A rosette is a coordinate system, associated with a set of rules, which ensure that all the plies maintain their correct relative angles at any location within the part boundary.
Status Term Definition
Web SRFI - Stitched Resin Film Infusion A method where stitched dry fiber preform is placed with a separate resin film on the tool, and then bagged with conventional nylon bag and autoclave cured.
Ed.3 STEP STandard for the Exchange of Product model data, the common name for ISO 10303
Web Sandwich construction A composite composed of a core (usually honeycomb or foamed plastic) to which two or more functional skins are attached
Ed.3 Security (1) with reference to data, controls that prevent illegal access, use or alteration
Ed.3 Security (2) with reference to data, the controls and processes that ensure that the data is not lost or corrupted.
Web Seed or Strategy Point a point on the ply definition surface that defines the starting location for draping and producibility analysis. (May want to keep for potential use)
Ed.3 Semantic Representation designates a certain way how information is being stored; it does not relate to the information content itself. Semantic Representation captures the meaning (intent) and relationships (context) of a character, word, phrase, sentence, paragraph, specification, or symbol without using any of the visual characters or constructs that are needed for a human to understand it - such as the letters, graphical symbols, lines and arrows used on engineering drawings.
The main purpose of Semantic Representation is to facilitate automated consumption of the data, e.g. for later re-use or for downstream applications. It applies to various types of data, such as PMI, Composite Material Definition, and others.
Example - The Semantic Representation of a Linear Dimension includes all of the information needed to understand the specification (the type of dimension, between which features it is defined...), without any of the graphic components such as dimension lines and extension lines, their direction, arrowheads and the dimension value.
Web Sequence is a container for a group of independent plies that do not overlap and are at the same stacking position and per best practice all the plies in a sequence will have the same material and orientation parameters. (Also called a Step, Layer, or Ply level) In manufacturing, each sequence would be inspected prior to moving on to the next operation. The sequencing used by engineering and manufacturing is identical in most situations, but not all. In the case of IML tooling, the Engineering stack-up definition will have to be inverted to create the proper "lay-down" sequencing required in manufacturing.
Ed.3 Simplified Activity Diagram a form of process description (cf NAS9300-004).
Web Spingback part distortion caused by complex interactions that is typically address with correction factors in the tool geometry.
Web Splice two pieces of material that are placed next to each other to produce a continuous surface. They can be placed adjacent to one another to form a butt slice or overlapping each other to generate an overlap splice.
Ed.3 Submission Information Package (OAIS) An Information Package that is delivered by the Producer to the OAIS for use in the construction of one or more AIPs.
Ed.3 Swim Lane an annotation of an activity or process diagram, in which each swim lane shows the involvement of a particular agent or actor.
Ed.3 System Architecture Framework an overview defining the interaction between the IT systems involved (NAS9300-003 5.6).
Status Term Definition
Web Tape A unidirectional material pre impregnated with resin that comes in widths up to 12 inches
Ed.3 Tessellated Presentation designates a specific implementation form of Graphic Presentation that is has been introduced during the development of STEP AP242 (ISO10303-242:2014). It supports all the characteristics of Graphic Presentation. It is based on data model for tessellated geometry and provides more efficient ways of storing the data, compared to Polyline Presentation. It supports curves (composed of straight line segments) and surfaces (composed of triangles).
Web Thermoplastic a plastic resin that can repeatedly be softened by heating and hardened by cooling
Web Thermoset a class of plastic resins that undergoes irreversible chemical reactions during curing cycle.
Web Tool Side The surface of the part that is first placed onto the tool or lay-up mandrel and is used to begin manufacturing ply sequencing. In most cases, it is equivalent to ply definition surface.
Web Tow A tow is a continuous strip of composite material similar to Tape - but, thinner. Common widths are 1/2" and 1/4"
Ed.3 Type Certificate a certificate issued by a regulatory agency which states that a type design conforms to airworthiness requirements. Each type certificate is considered to include the type design, the operating limitations, the type certificate data sheet, the applicable regulations with which the (FAA) Administrator records compliance, and any other conditions or limitations prescribed for the product.(AS9034).
Ed.3 Type Design in the aircraft industry, a design of a particular type of aircraft, where each type design requires a separate certification of airworthiness. (cf also AS9034).
Status Term Definition
Web Unidirectional Composite material with all fibers aligned in one direction
Ed.3 Unified Modeling Language (UML) a formalism in software design and construction used to describe object oriented systems - see Bibliography.
Ed.3 Use Case a description of a particular situation in which the system is used. Use cases form a part of the UML methodology (cf. EN9300-004 section 5 and UML reference).
Status Term Definition
Ed.3 Validation (1) the assurance that a collection of information has the correct representation (cf verification and NAS9300-003 5.3.5). In the context of LOTAR, this means that the model reconstructed from the archive data has not changed from the original - for example, it still has the same volume.
Ed.3 Validation (2) the process of establishing documented evidence that provides a high degree of assurance that a product, service, or system accomplishes its intended requirements. Validation ensures that 'you built the right thing'.
Ed.3 Validation Properties information calculated from a model or document whose invariance is used to validate the content after recovery, and so to demonstrate that the key characteristics are unchanged. For example, the volume of a solid in a CAD file.
Ed.3 Verification (1) the assurance that a collection of information has the correct content (cf validation, & NAS9300-003 5.3.5). In the context of LOTAR, verification rules test whether the structure of the model is correct, for example, that the faces that make up a shape knit together to form a solid, without gaps between the faces.
Ed.3 Verification (2) a quality process that is used to evaluate whether or not a product, service, or system complies with a regulation, specification, or conditions imposed at the start of a development phase. Verification ensures that 'you built it right'.
Web Void A pocket of gas trapped in a composite part. Distributed voids contribute to the porosity of the part.
Status Term Definition
Web Warp Threads that run along the length of the roll and perpendicular to the fill threads.
Web Weave A pattern of fabric formed from interlacing yarns. In a plain weave, the warp and fill fibers alternate to make fabric faces identical.
Web Weft Yarns running perpendicular to the warp in a fabric
Ed.3 Working Form Product Model the model used for creation and modification by the native application; it corresponds generally to the design stage of the Product Model; this Working Form is often in the native format of the COTS application.