AERONAU INFORMATION MANAGEM STUDY NOTE AIS- International TENTH MEETING SUMMARY. Annex 15 in. order to. Action by 1.1. data user in AIMSG 1.

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1 Internatinal Civil Aviatin Organizatin 07/11/2014 STUDY NOTE AERONAU UTICAL INFORMATION SERVICES-AERONAUTICAL INFORMATION MANAGEM MENT STUDY GROUP (AIS-AIMSG) TENTH MEETING Mntréal, 10 t 14 Nvember 2014 Agenda Item 1: AIM prcesses and requirements DATA QUALITY DEFINITION PROPOSED CHANGE AND REVIEW OF IMPACTS (Presented by Stéphane DUBET) SUMMARY This study nte addresses the existing incnsistency regarding the definitin f the term data quality between ICAO SARPs and Industry Standards. It assesses the use f the term in the current ICAO Annex 15 in rder t determinee the impact f a ptential change f thee ICAO definitin. It includes a recmmendatin t change the ICAO definitin and align itt with the ne used in Industry Standards, tgether with a strawman f crrelative amendments that wuld then be required. Actin by the AIS-AIMSG is in paragraph INTRODUCTION 1.1 ICAO Annex 15, the reference standard applicable t the aernautical data chain up t State AIS publicatin, defines data quality as a degree r level f cnfidence that the data prvidedd meet the requirements f the data user in terms f accuracy, reslutin and integrity. ACTION BY THE AIS- data as frm State AIS publicatin up t the end-user, defines data quality as a degree r level f AIMSG 1.2 EUROCAE ED76 / RTCA DO200A, the reference standard applicable t the aernautical cnfidence that the data prvided meet the requirements f the user. Thesee requirements include levels f accuracy, reslutin, assurance level, traceability, timeliness, cmpleteness, and frmat. 1.3 This Study Nte prpses t reslve this incnsistency in the definitinn f the same term applicable t different parts f the data chain by updating thee data quality definitin in Annex 15. It als reviews the main impacts f this change n the current ICAO material. (7 pages) SN 14 - Data Quality Definitin.dcx

2 DIFFERENCES IN DEFINITIONS OF DATA QUALITY 2.1 Recently, EUROCAE and RTCA decided t update the standards fr prcessing aernautical data (a.k.a. EUROCAE ED76 / RTCA DO200A). The bject is t make the standard up-tdate with reference t ICAO, ARINC and ther related EUROCAE standards in terms f standards fr data prcessing, in particular data quality. It cnsiders the requirements f the new ATM applicatin and takes due accunt f the latest state-f-the-art methds (Sftware Assurance Level, Data Assurance Level, etc.). The update als cnsiders suggested changes frm industry and authrities experience feedback. When starting the updating wrk, bth the industry and the authrities clearly cnfirmed the apprpriateness f the seven data quality characteristics (accuracy, reslutin, integrity, assurance level, traceability, timeliness, cmpleteness and frmat) defined in the riginal standard. 2.2 Whilst it was already knwn that the Industry Standards included seven characteristics f data quality when ICAO ne nly included three characteristics fr the same term, the need t reslve this incnsistency has been grwing tgether with the need fr cnsistent regulatin and standards applicable t data prcessing as a whle (i.e. fr the whle data chain). 2.3 Fr example, EASA is currently develping a set f rules applicable t bth Air Navigatin Service Prviders and (Industry) Data Prviders. Within this prcess, the difference in definitins between Industry Standards and ICAO SARPs was nticed, and it was decided t retain nly ne definitin based n the seven characteristics f data quality included in EUROCAE/RTCA material: a degree r level f cnfidence that the data prvided meet the requirements f the data user in terms f accuracy, reslutin, integrity (r equivalent assurance level), traceability, timeliness, cmpleteness and frmat. 3. USE OF DATA QUALITY IN ANNEX The term data quality is used in varius prvisins in Annex 15. In mst cases, the term is used as a generic term and culd cver any f the tw definitins mentined abve (quality definitin with either 3 r seven characteristics). There are yet sme cases where the prvisin wuld need t be updated if a change f definitin was made thse cases are highlighted in grey in the list belw mentining all ccurrences f the term in the current versin f Annex Nte 2. Guidance material n the aernautical data quality requirements (accuracy, reslutin, integrity, and traceability and prtectin requirements) may be fund in the Wrld Gedetic System 1984 (WGS-84) Manual (Dc 9674). Supprting data quality material in respect f data accuracy, publicatin reslutin, and integrity f aernautical data, tgether with guidance material in respect t the runding cnventin fr aernautical data, is cntained in RTCA Dcument DO-201A and Eurpean Organizatin fr Civil Aviatin Equipment (EUROCAE) Dcument ED-77 - Standards fr Aernautical Infrmatin (r equivalent) Nte 3 Guidance material n the management f aernautical data quality is included in the Manual n the Quality Management System fr Aernautical Infrmatin Services (Dc 9839). 3.3 Data quality specificatins Nte 2 Errr-prducing faults in the entire prcess may be mitigated by additinal data quality assurance techniques as may be required. These culd include applicatin tests fr critical data (fr example, by flight check); the use f security, lgic, semantic, cmparisn, and

3 - 3 - redundancy checks; digital errr detectin; and the qualificatin f human resurces and prcess tls such as hardware and sftware Nte 4 Different delivery methds and data media may require different prcedures t ensure the required data quality In rder t meet the data quality requirements, autmatin shall: ( ) Nte 2 Letters f agreement cncerning data quality between riginatr and distributr and between distributr and next intended user may be used t manage the aernautical infrmatin data chain The established quality management system shall prvide users with the necessary assurance and cnfidence that distributed aernautical data and aernautical infrmatin satisfy the aernautical data quality requirements fr accuracy, reslutin and integrity as specified in 3.2 and 3.3 and that the data traceability requirements are met thrugh the prvisin f apprpriate metadata as specified in 3.4. The system shall als prvide assurance f the applicability perid f intended use f aernautical data as well as that the agreed distributin dates will be met Each terrain data prduct specificatin shall include an verview, a specificatin scpe, data prduct identificatin, data cntent and structure, reference system, data quality, data capture, data maintenance, data prtrayal, data prduct delivery, additinal infrmatin, and metadata Bth terrain data prduct specificatins and bstacle data prduct specificatins shall include infrmatin that identifies the reference system used in the data prduct. This shall include the spatial reference system and tempral reference system. Additinally, bth data prduct specificatins shall identify the data quality requirements fr each data prduct. This shall include a statement n acceptable cnfrmance quality levels and crrespnding data quality measures. This statement shall cver all the data quality elements and data quality subelements, even if nly t state that a specific data quality element r sub-element is nt applicable Nte This includes an verview, specificatin scpe, data prduct identificatin, data cntent and structure, reference system, data quality, data capture, data maintenance, data prtrayal, data prduct delivery, additinal infrmatin, and metadata. 4. DATA QUALITY REQUIREMENTS 4.1 In the current Annex 15, data quality requirements (r specificatins ) are addressed in paragraph 3.3, which includes 3 subparagraphs fr the 3 characteristics f data quality. Thse paragraphs (accuracy, reslutin and integrity) then further refer t the existing tables in Annex 11, Annex 14 r Appendices in Annex 15 that prvide numerical requirements fr accuracy and reslutin, and a qualitative requirement fr integrity. 4.2 In the Industry Standards (EUROCAE ED76 / RTCA DO200A), the link between data quality and data quality requirements is made in the fllwing text:

4 - 4 - Operatrs, air traffic service prviders and natinal aviatin authrities have develped guidelines n the levels f risk that are judged t be acceptable fr different phases f flight. These are defined either n the basis f risk pertaining t a specific peratin, such as a landing, r as a risk f failure per flight hur. Frm an analysis f the ptential causes f failure, and the allwable risk, it is pssible t derive the allwable cntributin t failure f the individual cmpnents f the system. Based upn such a breakdwn, the user f aernautical data is able t determine the data quality requirements (i.e., accuracy, reslutin, assurance level, etc.) 4.3 The Industry Standards then develp further prvisins abut data quality requirements as a whle: The user f aernautical data shall ( ) determine data quality requirements, base the data quality f any particular data element upn the mst restrictive requirement fr its applicatin; assure the quality requirements are attained. (This duty may be discharged by btaining data frm a data supplier, accredited against this standard by an apprpriate rganisatin); The fllwing requirements apply t a data supplier/prcessr: ( ) The supplier/prcessr shall prvide data that meets the data quality requirements. The fllwing requirements shall be dcumented: The data quality requirements. The delivery frmat requirements. The identificatin f all the suppliers f data, used by the rganisatin, and the apprval status f each. Evidence f a mutual agreement f data quality requirements between the user and the data supplier shall be available. The data quality requirements shall be under cnfiguratin cntrl and bth parties shall apprve all mdificatins. 4.4 Numerical data quality requirements can be fund in Industry Standards (EUROCAE ED-77/98/99 and RTCA DO-201/276/272) fr accuracy, reslutin and integrity f navigatin, terrain and bstacle and aerdrme mapping data. Thse requirements are generally cnsistent with the nes in Annexes 11, 14 and The Industry Standards nly include actual stated requirements fr accuracy, reslutin and assurance level (r integrity). They d nt prvide specific (numerical r qualitative) requirements fr traceability, timeliness, cmpleteness, and frmat which are t be cnsidered thrugh the general prvisins n the data quality prcess mentined abve.

5 In summary, bth ICAO Annex 15 and Industry Standards deal with data quality requirements thrugh general prvisins n data quality as a whle n the ne hand and referencing tables fr accuracy, reslutin and integrity (and n ther characteristic) in separate dcuments / appendices. 5. TRACEABILITY, TIMELINESS, COMPLETENESS AND FORMAT 5.1 The fur additinal characteristics f data quality included in the Industry Standard are traceability, timeliness, cmpleteness and frmat. They are defined as fllws: Traceability: the degree that a system r a data prduct can prvide a recrd f the changes made t that prduct and thereby enable an audit trail t be fllwed frm the end-user t the data riginatr Timeliness: the degree f cnfidence that the data is applicable t the perid f its intended use Cmpleteness: the degree f cnfidence that all f the data needed t supprt the intended use is prvided Frmat: a structure f data elements, recrds and files arranged t meet standards, specificatins r data quality requirements The Industry Standards als include sme mre guidance n thse elements, as shwn in the extracts belw: Traceability Traceability requirements are typically stated in terms f the duratin f time that specific data elements must be traceable. It is recmmended that data be retained as lng as the data is in use. Timeliness Many data elements have an identified perid fr which the data is valid. The perid f validity may be based upn an update perid frm the supplier r the underlying characteristics f the data itself. An example f an update perid is when States publish aernautical data n a 28 day AIRAC cycle. An example f the perid being based n its characteristics is terrain data supprting a terrain applicatin: the perid f time fr which terrain data remains acceptable shuld be determined during evaluatin f the system. The requirement is t use valid, current data. This respnsibility rests with the end-user. The end-user may chse t discharge this respnsibility by purchasing a particular set f data, based upn its declared effective perid. Cmpleteness Cmpleteness includes defining any requirements that define the minimum acceptable set f data t perfrm the intended functin. One minimum set may be defined at time f equipment apprval, while a larger set may be identified by the end-user.

6 - 6 - The requirement defined at time f equipment apprval is typically just that there is a database that is cnsistent with planned peratins. The requirement defined fr the peratin is fr the database t cntain a particular set f data fr the area(s) where peratins are intended. Fr many systems, database size limitatins restrict the ttal amunt f data that can be stred. In this case, selectin criteria can be used t reduce the ttal cntent. These selectin criteria must be cnsistent with the peratinal requirements f the end-user. The respnsibility t have the necessary data fr perating areas is placed n the end-user. The end-user may chse t discharge this respnsibility by purchasing a particular set f data, based upn its declared cverage regin. Frmat The frmat f delivered data must be adequate t ensure that the data is interpreted in a manner that is cnsistent with the intent f the data. Fr transmissin r uplad, tw ptential frmats are available fr aernautical data: human readable r binary. With the advent f crss-industry standardisatin, highly structured markup languages, such as the Extensible Markup Language (XML) tends t replace the simpler humanreadable frmats based n psitin in the rw/clumn (such as ARINC 424) r field separatrs (such as the NOTAM frmat). There is als a trend fr the definitin f cnceptual/lgical data mdels, frm which the data cding specificatin is derived. This facilitates the use f different cding frmats, adapted t lcal needs, while ensuring interperability thrugh a cmmn semantic mdel. In all frmats, the definitin f each data element (a gegraphical psitin, a frequency value, an identificatin, etc.) includes: definitin f the data element; data type, range f values r list f values, as applicable; unit f measurement, if applicable; reference system, if applicable. 5.2 The Industry Standards prvisins fr traceability, timeliness, cmpleteness and frmat can apply in the Annex 15 cntext since they d make sense in the whle data chain. The definitins and guidance quted abve culd be re-used t ppulate new text in Annex 15 fr these additinal characteristics. 5.3 In summary f the previus paragraphs, the impact f a change f data quality definitin n the existing text f Annex 15 is limited t additin f fur definitins and fur sub-paragraphs in paragraph 3.3 t address the additinal fur characteristics f the ptential new definitin and a rewrding f that is in a mix between the tw definitins since it starts with data quality as accuracy reslutin and integrity but then adds traceability and timeliness, which are tw f the fur additinal characteristics f the ther definitin.

7 RECOMMENDATIONS 6.1 In rder t ensure cnsistency f standards within the whle data chain, it is recmmended t have nly ne definitin f a key-term such as data quality. 6.2 Given that bth the industry and sme authrities recently cnfirmed the apprpriateness f the definitin including seven characteristics fr data quality, it is recmmended t change the Annex 15 definitin and adpt the ne f the Industry Standards (EUROCAE ED-76 / RTCA DO-200A and their upcming revisin). 6.3 Assuming this recmmendatin is agreed, it is prpsed that new text is included in Annex 15 based n the existing material in Industry Standards. This new text shuld be limited t 4 new subparagraphs in the paragraph n Data quality specificatins. A minr update f the text in shuld als be carried ut. Appendix 1 t this Study Nte includes a draft strawman f such amendments fr Annex 15. If deemed necessary, sme additinal text culd als be develped fr inclusin in PANS- AIM. 7. THE AIS-AIMSG IS INVITED TO: 7.1 The members f the grup are invited t discuss the tpic presented abve and t prvide feedback n the prpsed mdificatins t Annex 15. END