(3) Data Processing Requirements. The data supplier must comply with RTCA/DO-200A, sections 2.4 and 2.5. The following paragraphs clarify certain aspects of those requirements.
(a) Data Alteration. The data supplier must not alter the data from any supplier without informing the data originator of the change and endeavoring to receive concurrence in a timely manner (see RTCA/DO-200A, section 2.4.2).
1. For navigation databases, any change is considered an alteration of data when the resultant operation of the aircraft does not comply with the instrument flight procedure instructions published by the Contracting State, such as changing a heading to a track. This requirement to notify the data originator only applies to the alteration of the data or procedure, and does not apply to assembling, translating, selecting, or formatting the data.
2. For navigation databases, changes that do not alter the results of the published instrument flight procedures and navigation fixes are not considered alteration of data.
For example, a procedure published as “Direct to ABC” can be coded as a DF path terminator under ARINC 424. The DQRs are used as the basis for evaluating changes.
Note: For changes of this type, it is the data supplier’s responsibility to ensure the changes do not modify the original intended flight track.
3. If concurrence with the data originator cannot be obtained, the data supplier who alters the data assumes the role of the data originator and the associated responsibilities (see paragraph 13b(3)(b)). Data suppliers who alter source data must document the criteria for informing the data originator of data alteration and consider all potential conflicts with other supplied data.
4. Operations may reveal problems or conditions that could result in undesirable or potentially unsafe operations. Quality control processes, procedures, and records must exist for correcting deficiencies or preventing potentially unsafe operations.
(b) Data Origination. Criteria for originated data must be clearly defined, including documenting the validation process for the data origination. This requirement applies to altered data where concurrence with the originator could not be obtained (see paragraph 13b(3)(a) above). The quality management (QM) requirements (RTCA/DO-200A, section 2.5) must define data elements that can be originated or can be altered. The QM requirements must also define the level of review and approval required for each originated data element. Originated data must be distinguishable from Contracting State-provided data. For example, in a navigation database an originated approach procedure would not have the same title as a Contracting State-published approach, or the supplier could provide a separate list of originated data. The applicant must validate the data not from Contracting State AIPs.
RTCA/DO-272B, section 3.9.2 and RTCA/DO-276A, section 6.1.5 both state, “demonstration by actual use of the database in simulation or flight-tests” provides a means, but not the only means for demonstrating the acceptability of originated data.
14. Verification and Validation of Data.
a. In an aeronautical data chain, data may be received from any data supplier. If a data supplier has complied with the requirements of RTCA/DO-200A, evidenced by FAA LOA, the responsibility to ensure that stated DQRs are attained is discharged (reference RTCA/DO-200A, section 1.4 and 2.3.3 1). Likewise, for data published in the AIP, or provided via an official government source, the responsibility to assure that stated DQRs are attained is discharged.
Such data does not require verification or validation. Assurance Level 1 or 2 data obtained from other suppliers must be verified and validated appropriately prior to delivery and managed under an approved process. Refer to the RTCA/DO-200A, appendix A, Glossary, for the definitions of assurance level, verification, and validation as the terms apply to this AC.
b. Acceptable techniques for the verification and validation of airport map data can be found in RTCA/DO-272B, section 3.9.
c. Acceptable techniques for the verification and validation of terrain and obstacle data can be found in RTCA/DO-276A, sections 6.1.4 and 6.1.5.
15. Changes to DQRs and Identification of Non-Compliant Data. The process for establishing new configuration baselines should be identified in the configuration management plan.
a. Changes within the DQRs may impact the ability of the equipment to satisfy the intended function of the installed equipment. Changes to the DQRs must be coordinated between the data supplier and receiver. Sufficient advance notice of changes should be given to allow subsequent participants in the data chain (avionics manufacturer, original equipment manufacturer (OEM) and potentially the operator) sufficient time to review the effect of the change as described in paragraph 22b of this AC.
b. A data supplier may have certain data elements that do not comply with the three assurance levels identified in RTCA/DO-200A, appendix B, paragraph B.1.3. The DQRs for the non-compliant data should be assigned an assurance Level 4 (see Note below), indicating that it may not satisfy safety objectives. If this data is delivered as RTCA/DO-200A compliant, then the agreed-upon DQRs should identify this data and the fact that the assurance level is Level 4.
The Level 4 data must be distinguishable from any compliant data through a configuration management process, and does not need to be distinguished in the database itself. The operator is ultimately responsible for ensuring that Level 4 data meets the quality requirements for its intended application.
Note: Level 4 data are defined as those elements that may not comply with the requirements of RTCA/DO-200A.
16. Tool Qualification. The data supplier must comply with the elements of RTCA/DO-200A, section 2.4.5. Tool qualification processes must distinguish between production and verification tool activities and must include methods used to demonstrate valid tool output. Tool test case
15 development must identify sufficient test cases to properly test tools to meet the required data quality for the data output.
Note: For reference purposes, the data supplier can find guidance on how to carry out tool qualification, definitions of tool qualification classifications, and greater detail of the activities needed to support tool qualification in RTCA/DO-178B, section 12.2.
17. Exceptions to RTCA/DO-200A. Digital Error Detection Techniques. Table 1 of this AC replaces Table C-1 of RTCA/DO-200A. This change reconciles the RTCA/DO-200A guidance with aircraft design assurance guidelines (AC 25.1309, AC 23.1309, etc.). This change does not impact the acceptability of data in Contracting State AIPs, where table C-1 (RTCA/DO-200A, appendix C, paragraph C.2.2.1, Table C-1) may still be used.
Table 1: Relationship Between Assurance Levels and Digital Error Detection Performance Assurance Level Probability of Undetected corruption 1 < 10-9 2 < 10-5 3 Not applicable
18. How does this guidance apply to origination of data?
a. RTCA/DO-200A, section 1.5.4.2 describes aeronautical data origination, however, oversight of Contracting State data is outside the scope of this AC.
Note: For navigation data, ICAO Annex 15 states that each Contracting State must take all necessary measures to ensure the aeronautical information/data it provides is adequate, of required quality (accuracy, resolution and integrity), and provided in a timely manner for the general conditions under which the service or facilities are available for international use.
b. Contracting States are encouraged to follow RTCA/DO-200A, RTCA/DO-201A, RTCA/DO-272B, and RTCA/DO-276A and apply the standards to the origination of the data.
ICAO defines the standards for Contracting State data.
Note: Any non-compliance with ICAO standards may impact safety.
The Contracting State should first attempt to comply with ICAO requirements. If the Contracting State is unable to comply, it should communicate all non-compliance through the AIP.
c. If any participant in the aeronautical data chain supplements Contracting State originated data or originates data that is independent of the Contracting State, that participant must meet the requirements in paragraph 13 of this AC regarding the origination of the aeronautical data.
19. What is the Relationship between RTCA/DO-200/200A and Airworthiness Approval?
This section provides guidance on the definition of DQRs for systems that use aeronautical data.
manufacturers should define these requirements upon obtaining a Type 2 LOA for existing systems, alternative means for existing systems with RTCA/DO-200 based compliance, or at the time of airworthiness approval of a new system.
a. Requirements for Existing Systems with RTCA/DO-200 Compliance (prior TSOA, TC, or STC approval). Many aircraft and avionics manufacturers have obtained approval for systems prior to the issuance of this AC, and may not have identified its DQRs. For such systems, the DQRs for the avionics should be identified as described in RTCA/DO-200A prior to a data supplier obtaining a Type 2 LOA (see paragraph 9 of this AC). These requirements may be established by the design approval holder or by a data supplier covered under a production certificate provided the data supplier has access to the original documentation for the avionics.
For example, flight management system (FMS) suppliers to an OEM may document compatibility with their FMS without the direct involvement of the OEM. The requirements should be based upon the original design documentation, supplemented as necessary to address the data quality characteristics. Typically, the data format accuracy and resolution is specified in the original RTCA/DO-178B documentation, and the corresponding assurance level integrity requirements are specified in RTCA/DO-201A, RTCA/DO-272B, or RTCA/DO-276A. The data accuracy, resolution, and assurance level may need to be re-examined for small RNP values or other operations not addressed in RTCA/DO-201A.
Note: DQRs reviewed and approved in accordance with AC 20-115B, RTCA, Inc. document DO-178B, do not need to be re-approved by the FAA to comply with this AC. Any additional documentation for data quality, (e.g., assurance level), that does not affect the TC or STC approved design, but is developed in support of this criteria, is supplementary information in support of the data supplier Type 2 LOA. This means no other certification activity is required for the airborne systems or equipment. Supplementary documentation changes may be reflected in documents separate from the TC or STC design documentation, but should provide the necessary references to such documentation. The TC or STC design holder may incorporate supplementary documentation into the certification basis at the next opportunity.
b. Requirements for Existing Systems with RTCA/DO-200A Compliance (prior TSOA, TC, or STC approval). The manufacturer must identify the DQRs. Many aircraft and avionics manufacturers have obtained approval for systems prior to the issuance of this AC, and may not have identified its DQRs. For such systems, the DQRs for the avionics must be identified prior to a data supplier obtaining a Type 2 LOA (see paragraph 9 of this AC). These
17 requirements may be established by the design approval holder or by a data supplier covered under a production certificate provided the data supplier has access to the original documentation for the avionics. For example, FMS suppliers to an OEM may document compatibility with its own FMS without the direct involvement of the OEM. The requirements should be based upon the original design documentation, supplemented as necessary to address the data quality characteristics. Typically, the data format accuracy and resolution is specified in the original RTCA/DO-178B documentation, and the corresponding assurance level integrity requirements are specified in RTCA/DO-201A, RTCA/DO-272B, or RTCA/DO-276A. The data accuracy, resolution and assurance level may need to be re-examined for small RNP values or other operations not addressed in RTCA/DO-201A.
Note: DQRs reviewed and approved in accordance with AC 20-115B, RTCA, Inc. document DO-178B, do not need to be re-approved by the FAA to comply with this AC. Any additional documentation for data quality, (e.g., assurance level), that does not affect the TC or STC approved design, but is developed in support of this criteria, is supplementary information in support of the data supplier Type 2 LOA. This means no other certification activity is required for the airborne systems or equipment. Supplementary documentation changes may be reflected in documents separate from the TC or STC design documentation, but should provide the necessary references to such documentation. The TC or STC design holder may incorporate supplementary documentation into the certification basis at the next opportunity.
c. Requirements for New Systems. For new systems requiring aeronautical data assurance, the manufacturer must identify the DQRs as part of the airworthiness approval documentation.
20. Defining DQRs.
a. An OEM for aircraft and avionics may use the requirements defined in section 2 of RTCA/DO-200A as a means to implement a “QM” process and to define the DQRs for the aeronautical database. The DQRs must be under configuration control. RTCA/DO-200A, section 2.3 and appendix B, provides an acceptable means to define the DQRs. As described in RTCA/DO-200A, aeronautical data is characterized by its accuracy, resolution, assurance level, traceability, timeliness, completeness, and format. However, timeliness and completeness are subsequently defined by the operator and need not be addressed by the design approval holder.
For navigation databases, this definition could include data elements with corresponding accuracy, resolution and assurance level, record types and interrelationships to define paths (e.g., ARINC 424 path terminators if used within the avionics), any filters being applied to those record types, and company-specific format requirements (field by field description of what is delivered in the packed data). For terrain and obstacle data, RTCA/DO-276A, section 3 defines a minimum set of DQRs that could be used for terrain awareness and warning systems. The applicant must define DQRs for other applications (e.g., synthetic vision systems or overlay of terrain on attitude indicator). For airport data, RTCA DO-272B sections 2 and 3 define a
18 minimum set of DQRs that could be used for airport map displays. The applicant should demonstrate that the airport mapping DQRs meet the requirements for its intended function and should document the means by which the data will be maintained.
b. Intended Function. The DQRs must be consistent with the intended function of the equipment identified as part of the normal design approval. One or more of the data qualities can affect the equipment. The system certification documentation defines the system functions and any dependencies on the data (i.e., DQRs). For example, with navigation systems, this includes all uses of the system, such as navigating on published airways or routes, standard arrivals, departures, and specific types of approach operations. RTCA/DO-201A provides guidance on requirements supporting area navigation and the RNP operations described in RTCA/DO-236B.
(1) Many aspects of the DQRs are addressed to support compliance with AC 20-115B. DQRs reviewed and approved in accordance with AC 20-115B do not need to be re-approved by the FAA to determine compliance with this AC. However, the applicant should ensure that the DQRs developed under the RTCA/DO-178B standard are correctly established for the data’s intended use (see RTCA/DO-200A, section 2.3), and may develop supplementary documentation to address some DQRs.
(2) Navigation, obstacle, and airport map data changes frequently. In order to retain data currency, this AC provides an acceptable means for associating the DQRs for the aeronautical data with the aircraft type design without requiring the data (e.g., loadable media) become part of the RTCA/DO-178B software life cycle.
Note: When RTCA/DO-201A, RTCA/DO-272B, RTCA/DO-276A, or other comparable criteria do not address the source data for the data product, the data quality may only reflect the data supplier’s processes and assurances specified by its DQRs.
21. Failure Condition Classification. The required assurance level for the data process must be identified and consistent with the intended use of the equipment. Because integrity of a process usually cannot be numerically quantified, the integrity requirement may be defined by an assurance level. RTCA/DO-200A, appendix B provides guidance on the assignment of an assurance level, based on the system safety assessment for the intended function. For example, with RNAV operations and basic RNP operations, all supporting data should comply with RTCA/DO-201A.
22. Identification and Configuration Control.
a. Configuration control processes should include traceability between the DQRs and a database specification. The DQRs can also be referenced in the instructions for continuing airworthiness.
b. Changes to the DQRs must be evaluated per the change control process of the TSOA and/or TC /STC approval. This does not preclude changes to the data itself that is expected to change, remain current, or support operations in different geographic regions. Changes to the
19 DQRs must be evaluated to determine whether they have a major, minor, or no effect on the system’s intended function. The LOA holder must demonstrate that its processes ensure this evaluation occurs.
Note: The aircraft manufacturer, avionics manufacturer or systems integrator may incorporate any additional configuration management and control requirements found in other existing standards. Database configuration management should address identification/part number, version control, data quality assurance/management, coordination processes (e.g., reporting of errors), and change management.
23. Instructions for Continued Airworthiness (ICA) (14 CFR § 21.50(b)). For new projects, if the database is not identified as part of the type design, the ICAs should require that the data comply with the DQRs for the target hardware. For general aviation, if the database is loaded into the avionics through pilot action, the operator’s manual should contain the procedures for ensuring the database complies with the DQRs. A LOA held by the avionics manufacturer and available to the equipment user will be necessary to determine the database is compliant with RTCA/DO-200A and compatible with its avionics.
Note: If the OEM or TSOA holder is involved in the delivery of aeronautical data to operators, the OEM or TSOA holder should obtain FAA acceptance of its aeronautical data process in accordance with paragraph 13 of this AC.
24. The Need for Database Integrity.
a. The aeronautical applications and functions that depend on databases are widespread.
Since the 1970s, installed systems relied on databases to support intended functions, such as navigation data used to facilitate the presentation of flight information to the flight crew. Prior to issuance of AC 20-153, the FAA had not developed a process for acceptance or oversight of aeronautical databases and its compatibility with applications. Consequently, no guidance existed for data suppliers on how to obtain FAA acceptance of its aeronautical data processes.
b. With new performance-based operations requiring database integrity, guidance on how to obtain FAA acceptance is necessary. Due to the advancement of RNP and its dependence on data quality, RTCA developed standards to achieve the higher levels of assurance necessary for these data and data processes. In operations, such as those for RNP, where the operating margins are based upon specific levels of system performance, reducing and mitigating errors is a key safety factor. While data quality is often essential for primary functions, it is also beneficial to all other similar functions and applications, such as RNAV, terrain situational awareness, etc. Consequently, we provide this guidance material to address database processes and quality.
c. Aviation safety can be significantly degraded by aeronautical information errors related to the content of aeronautical databases, such as:
(1) Errors Generated by the Contracting State. Each Sovereign Nation or ICAO Contracting State publishes aeronautical data in support of navigation and other functions. This data frequently contains source origination errors, caused by factors such as survey errors, incorrect association of latitude/longitude with a fix, or invalid magnetic variation. Errors related to data entry or processing prior to release into the public domain also occur.
(2) Errors Generated by the Data Service Provider. Companies processing and integrating data from multiple Contracting States can also introduce errors. These errors typically result from the translation process, errors related to data entry or processing, misinterpretation of the Contracting State data, modifying the Contracting State data to achieve compatibility with the end application, or changing the data format in a manner incompatible with the end application.
(3) Errors Generated by the Avionics Manufacturer. Errors have occurred due to the processing or use of the data by the avionics manufacturer. Conversion of the data into the final data format has created errors by rendering the data incompatible with implementation assumptions (e.g., incompatible path/terminator combinations, etc).
25. Related Federal Aviation Regulations. 14 CFR parts 21, 23, 25, 27, 29, 43, 91, 121, 125, and 135.
a. Some U.S. operations (e.g., RNP procedures, RNAV routes, etc.) will require the operator to validate its data or obtain data from an accepted data supplier (reference 14 CFR §
91.503 requirement for the operator to have aeronautical data in current and appropriate form).
b. For foreign operations where the CAA requires approved data suppliers (e.g., Precision Area Navigation (P-RNAV) operations in Europe), a LOA for the relevant supplier provides one means of complying with 14 CFR § 129.17.
Note: Paragraphs 19 – 23 of this AC address the definitions of DQRs applicable to ensuring compliance with the airworthiness regulations for intended function and failure effects of equipment, systems and installations.
26. Related References.
a. FAA ACs. Order copies of Advisory Circulars from the U.S. Department of Transportation, Subsequent Distribution Office, M-30, Ardmore East Business Center, 3341 Q 75th Avenue, Landover, MD 20785. You can also get copies from our website at www.faa.gov/regulations_policies/advisory_circulars/.
(1) AC 20-115, RTCA, Inc., Document RTCA/DO-178B.
(2) AC 25.1309-1, Systems Analysis and Design.
(3) AC 23.1309-1, Equipment, Systems, and Installations in Part 23 Airplanes.
b. ICAO Documents. Publications are available from ICAO, Attention: Customer Service unit, 999 University Street, Montreal, Quebec, Canada H3C5H7. Telephone +1 514-954-8022, facsimile: 514-954-6769, sitatex YULCAYA, email: sales@icao.int or on line at http://www.icao.int. ICAO Annex 15, Aeronautical Information Services.
c. RTCA, Inc. Documents. You can order copies of RTCA documents from RTCA, Inc., 1828 L Street NW, Suite 805, Washington, DC 20036. Telephone: (202) 833-9339, or online at http://www.rtca.org.
(1) RTCA/DO-178B, Software Considerations in Airborne Systems and Equipment Certification, dated December 1, 1992 and its equivalent, EUROCAE document ED-12B, Software Considerations in Airborne Systems and Equipment Certification.
(2) RTCA/DO-200, Preparation, Verification and Distribution of User Selectable Navigation Data Bases, dated November 28, 1988.
(3) RTCA/DO-201, User Recommendations for Aeronautical Information Services, dated November 28, 1988.
(4) RTCA/DO-200A, Standards for Processing Aeronautical Data, dated September 28, 1998 and its equivalent, EUROCAE document ED-76, Standards for Processing Aeronautical Data.
(5) RTCA/DO-201A, Standards for Aeronautical Information, dated April 19, 2000 and its equivalent, EUROCAE document ED-77, Standards for Aeronautical Information.
(6) RTCA/DO-236B, Minimum Aviation System Performance Standards: Required Navigation Performance for Area Navigation, dated October 28, 2003.
(7) RTCA/DO-272B, User Requirements for Aerodrome Mapping Information, dated April 14, 2009 and its equivalent, EUROCAE document ED-99B, User Requirements for Aerodrome Mapping Information.
(8) RTCA/DO-276A, User Requirements for Terrain and Obstacle Data, dated August 3, 2005 and its equivalent, EUROCAE document ED-98A, User Requirements for Terrain and Obstacle Data.
(9) RTCA/DO-291A, Interchange Standards for Terrain, Obstacle and Aerodrome Mapping Data dated April 14, 2009 and its equivalent, EUROCAE document ED-119A, Interchange Standards for Terrain, Obstacle and Aerodrome Mapping Data.
d. Society of Automotive Engineers (SAE) International Documents. Order SAE documents from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001.
Telephone (724) 776-4970, fax (724) 776-0790. Copies may be ordered online at http://www.sae.org.
(1) ARP 4754, Certification Considerations for Highly Integrated or Complex Aircraft Systems.
(2) ARP 4761, Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment.
e. Airlines Electronic Engineering Committee (AEEC), ARINC, Inc. Documents.
Order copies of ARINC documents from ARINC Incorporated, 2551 Riva Rd., Annapolis, MD, 21401. Telephone +1 800-633-6882, fax +1 410-956-5465. You can also get copies online at www.arinc.com.
(1) ARINC Specification 424, Standard, Navigation System Data Base.
(2) ARINC Specification 816, Embedded interchange Format for Airport Mapping Database.
Susan J. M. Cabler Assistant Manager, Aircraft Engineering Division
Appendix 1 A1-1 Appendix 1. Application for a LOA
Figure 1. Sample of a Type 1 LOA Application
The ACME Data Company PO Box 1 Nowhere, Arkansas 71953
FAA – Southwest Region 2601 Meacham Blvd Fort Worth, Texas, 76193
Manager, Aircraft Certification Office, ASW-150
Subject: Request for New Type 1 Letter of Acceptance for ACME Company’s Aeronautical Data Process
To Whom It May Concern:
ACME Data Company is applying for a new Type 1 letter of acceptance for our aeronautical data process. We comply with AC 20-153A and RTCA/DO-200A and request your review of the enclosed data being submitted in support of this application. The ACME Data Company develops navigation information per the data quality requirements specified in ACME Document XXX.XX. Acceptance of our aeronautical data process is requested based on the specification and control of these data quality requirements, compliance with AC 20-153A and the documented procedures for processing data. This navigation information is not intended to be directly loaded in any aircraft system.
The information will be developed at the ACME Data Company, 3000 Hill Street, Nowhere, Arkansas 71953. The ACME Data Company hereby certifies that the Data Quality Requirements, Data Processing Procedures, and Quality Management System, which are in accordance with RTCA/DO-200A, section 2 has been established and the navigation information is produced in accordance with this system.
Your efforts in support of this request are most appreciated.
Sincerely,
Administrator, ACME Data Company
Enclosures:
1 copy ACME drawings, quality control manual, specifications and processes.
Appendix 1 A1-2 Figure 2. Sample of a Type 2 LOA Application
The ACME Avionics Manufacturer PO Box 1 Nowhere, Arkansas 71953 FAA – Southwest Region 2601 Meacham Blvd Fort Worth, Texas, 76193 Manager, Aircraft Certification Office, ASW-150 Subject: Request for New Type 2 Letter of Acceptance for ACME Company’s Aeronautical Data Process To Whom It May Concern:
The ACME Avionics Manufacturer is applying for a new Type 2 letter of acceptance for our aeronautical data process. We comply with AC 20-153A and RTCA/DO-200A and request your review of the enclosed data being submitted in support of this application. The ACME Avionics Manufacturer receives data from other sources, and develops navigation information per the data quality requirements specified in ACME Documents XXX.XX and YYY.YY, respectively.
Acceptance of our aeronautical data process is requested based on the specification and control of these data quality requirements, compliance with AC 20-153A and the compatibility of the delivered data with the following products:
ACME FMS Model XY, P/N 12345-23a ACME FMS Model Z, P/Ns 56789-1 through 56789-8 ACME has established compatibility with these systems based on the original software design documentation approved under the original TSO authorization. Compilation of data to the compatible format is accomplished using ACME Tool 123.
The information will be developed at the ACME Avionics Manufacturer, 3000 Hill Street, Nowhere, Arkansas 71953. The ACME Avionics Manufacturer hereby certifies that the Data Quality Requirements, Data Processing Procedures, and Quality Management System, which are in accordance with RTCA/DO-200A, section 2 has been established and the navigation information is produced in accordance with this system.
Your efforts in support of this request are most appreciated.
Sincerely,
Administrator, ACME Avionics Manufacturer
Enclosures:
1 copy ACME drawings, quality control manual, specifications and processes.