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(4) Appropriate retention of messages (archive) requiring later action (printer copies of oceanic clearances etc.).
(5) Appropriate resolution of message uncertainty.
(6) Appropriate use of data link and voice, respectively, where circumstances or operations dictate (e.g., voice for backup or clarification of non-normal situations).
(7) If an ATC data link clearance contradicts a voice clearance, comply with the voice clearance.
c. Data Link Communications Good Operating Practices. The following data link communications "good operating practices" have been identified:
(1) To preclude unnecessary communication and possible interference with ground facilities, data link communications should be used only in conjunction with facilities specified for the route or procedure to be flown. An example would be as follows: data link communications with other than designated ground facilities should be accomplished only as necessary to support flight plan or flight operations requirements.
(2) Free text data link messages should use standard aeronautical terminology, accepted abbreviations, and be written in English.
(3) When appropriate, verify data link communication functions prior to departure.
d. Operator Responsibilities. Operators have the following general responsibilities regarding data link communications:
(1) Verify data link communications functionality for each environment to be used and when new or modified components or software are introduced.
(2) Assure follow up and evaluation of exceptional data link events.
(3) Periodically assess data link communications training, checking, and maintenance programs to ensure their correctness, pertinence, timeliness, and effectiveness.
e. ATC Responsibilities. The operator can expect ATC to adhere to the following procedures.
(1) Ensure that controllers do not knowingly issue data link instructions that are contrary to voice instructions when data link is being used.
(2) Be aware of pertinent data link communication program changes.
(3) Train ATC specialists about data link expected flightcrew responses to data link advisories, and permit familiarization flights for specialists on data link equipped aircraft to the extent possible.
(4) When requested by the flightcrew, provide clarification or confirmation of data link messages and assist in returning to the assigned clearance, if appropriate. Issue additional clearance instructions when necessary.
(5) Advise pertinent FAA offices via data link communications questionnaires about airspace or airports where data link communication problems occur. This facilitates initiation of corrective actions related to data link communication enhancements, procedures, and airspace adjustments.
(6) Advise FAA of other hazardous conditions, situations, or events which may be related to data link communications.
13. DATA LINK EVENT REPORTING.
a. General. Operators and manufacturers are encouraged to develop procedures to ensure effective identification, tracking, and follow up of data link-related events, as appropriate. Such procedures should focus on providing useful information to:
(1) Properly assess the importance of data link events.
(2) Follow up on information related to specific data link events as necessary.
(3) Keep the industry and FAA informed on the performance of data link in the NAS and international operations.
b. Pilot Reports.
(1) "Data Link-Specific" Reports. Pilots should make the following reports for unusual data link events, as necessary:
(a) Upon query from ATC, or after an inadvertent deviation from an ATC clearance, make radio communications as appropriate to report the event. Refer to the Aeronautical Information Manual (AIM), Section 4, ATC Clearances, for guidance regarding recommended phraseology, and Appendix 4 of this AC for acronyms and abbreviations.
(b) Reports, as specified by the operator, concerning data link anomalies, procedural difficulties, or system failures typically are made by pilots through one or more of the following methods:
• Pilot/observer questionnaire,
• Logbook entry,
• ACARS, etc, and
• Other record used by that operator (such as a "Captain's Report"). An example of a typical reporting form for data link event information is shown in Appendix 1.
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(2) Other Reports Incidental to Data Link.
(a) Near Mid-Air Collision, NMAC Reports. Flightcrews should continue to submit NMAC reports in accordance with existing policies and procedures. (Crews should be aware that there is no requirement to submit an NMAC report solely due to a data link event).
(b) Aviation Safety Reporting System (ASRS) Reports. ASRS reports may be filed at the discretion of the flightcrew.
(c) Operator/Maintenance Department Reports. Operator maintenance department personnel should make data link-related reports as necessary. Submit reports of frequent or systematic data link problems that may relate to system performance, manufacturers, and/or data link vendors to the PAI or PMI, as appropriate.
(d) FAA ATC. Report the following:
1. Data link events to FSDOs or CMOs as necessary; and
2. Any exceptional data link-related events regarding NAS performance to the Air Traffic Procedures Division.
(e) Data Link Manufacturer Reports. Data link avionics manufacturers report problems found with specific data link systems in accordance with established Service Difficulty Report (SDR) procedures. Generic problems, such as those that may relate to the definition of ARINC 622 or 745 characteristics or of documents listed in paragraph 4(e) should be reported to the Aircraft Engineering Division, AIR-200 (Production/Airworthiness).
14. FOREIGN AIR CARRIERS.
a. General. Foreign air carriers may use data link communications when operating in U.S.
airspace. Foreign air carriers are not required to install and use data link communications for any aircraft or operations even though separation services may be provided by a U.S. ATC facility
(e.g., in oceanic airspace), unless separation standards or a desired flight plan classification are based on its use.
b. Data link Communications Approval for Foreign Air Carriers. FAA does not approve data link communications installations, training programs, MELs, or maintenance programs for foreign operators operating non-U.S. registered aircraft. Such authorizations are addressed as specified by the State of the Operator. However, since compatibility of data link communications within U.S. airspace is essential, part 129 operations guidelines for data link communications are issued by this AC. Compliance with these data link communications provisions ensures both data link communication system and procedural compatibility. The issuance of OpSpecs or an amendment to existing OpSpecs for data link communications must take place prior to a foreign air carrier operating a data link communication-equipped aircraft in Domestic U.S. airspace, or with U.S. Domestic facilities. Standard provisions for foreign air carriers for data link communications are shown in Appendix 3.
c. Application and Approval. Foreign air carriers should contact their FAA POI to obtain application information for part 129 data link communications OpSpecs in U.S. airspace. When a foreign air carrier submits the necessary information to the respective PI, showing that its aircraft comply, the PI approves those OpSpecs or an amendment. Standard OpSpec provisions regarding data link communications for foreign air carriers are shown in Appendix 3. Although not mandatory, foreign operators should comply with the provisions of this AC, or equivalent provisions specified by the State of the Operator or specified by ICAO.
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Appendix 1 APPENDIX 1. SAMPLE DATA LINK EVENT REPORTING INFORMATION Date____________________ Time__________________
Operator/Flight #_________ Origination_____________ Destination_____________
Submitted to: ATC Inquiry___________ Other_________________
Phase of Flight___________ Position__________________ Altitude_____________
(Optional for Aircrew:)
Name_____________ Phone (W)_______________ Phone (H)_____________
Describe Event:
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Appendix 2 APPENDIX 2. DATA LINK COMMUNICATIONS MEL AND MMEL PROVISIONS
1. EXAMPLE OF A MINIMUM EQUIPMENT LIST (MEL). Each operator intending to have authority to dispatch an aircraft with a data link communication system or component temporarily inoperative must do so in accordance with provisions of an MEL. MEL’s are approved for each operator and type aircraft, within provisions of the Federal Aviation Administration (FAA) MMEL for that type. When proposed, MEL provisions are consistent with the FAA MMEL; principal operations inspectors (POI) may approve the MEL. If less restrictive MEL or different MEL provisions are requested, a proposal for consideration of an FAA MMEL change must be forwarded to the Aircraft Evaluation Group (AEG) assigned for that aircraft type. Enhanced features (those above and beyond the basic data link communication system) may be inoperative, provided that the inoperative features do not degrade the system; for example, data link printers.
Equipment Condition Data link system C-0 (M) May be inoperative provided the system is deactivated and secured.
Dual data link or data link controls or displays C-21 (0) May be inoperative on the flying pilot side provided that:
(a) Appropriate data link elements and functions are operative on the non-flying pilot side, and
(b) Display data link indications are visible to the flying pilot.
(0) May be in-operative on the non-flying pilot side, provided that:
(a) The required minimum voice communications are operative and that voice procedures are approved for the route or procedures to be flown, and
(b) The required minimum voice command communications audio functions are operative, and voice procedures may be used for the route or procedures to be flown.
Data link Printer C-0 (0) May be inoperative provided all other data link display and control functions are operative. All elements of each data link transmission can be retrieved, displayed and reviewed by the flightcrew or may be inoperative if relevant operations or functions are not predicated on data link use (e.g., print control function not authorized if the printer is inoperative).
Appendix 2
2. EXAMPLE OF A DATA LINK MMEL PROVISION.
Boeing 747-400
23 COMMUNICATIONS | | | | | | | | | | -XX-1 Digital Data Link |D | - | - | Any in excess of those required by| Communications Systems | | | | Regulation may be inoperative. | | | | | | -XX-2 Analog Data Link |D | - | - | Any in excess of those required by| Communications Systems Regulation may be inoperative. | NOTE: The provisos and repair category intervals are intended to grant the operator sufficient relief during the initial stages of the data link implementation. This is intended to promote the installation process, as well as support the use of a partial system. Both equipment reliability and operational experience will dictate, if any, revision to this MMEL relief should be considered after the installation phase is completed.
Appendix 3 APPENDIX 3. PART 129 PROVISIONS FOR USE OF DATA LINK IN U.S. AIRSPACE
1. The issuance of operations specifications (OpSpecs) or an amendment to existing OpSpecs for data link communications must take place prior to a foreign air carrier operating a data link communication-equipped aircraft in domestic U.S. airspace, or with U.S. domestic facilities.
2. An appropriate data link must be installed and operated on suitable frequencies specified by air traffic control (ATC) during flight in U.S. airspace if procedures are predicated on its use. A unique and specific address, the International Civil Aviation Organization (ICAO) 24-bit aircraft identification, must be assigned to the airplane and the data link must recognize this address.
When properly set, the unique address may not be altered, set to a duplicated address, or set to an address that potentially interferes with ATC or data link safety functions.
3. A data link capable of coordinating with air traffic facilities using Radio Technical Commission for Aeronautics (RTCA) DO-219 or other equivalent standards must be installed if operations will be predicated on its use. The data link system should be operated in an appropriate data link mode during flight in U.S. airspace using data link, except as provided for by the Minimum Equipment List (MEL) provisions acceptable to the State of the Operator.
4. Training and procedures for use of data link as specified by ICAO, this advisory circular (AC), or other equivalent criteria acceptable to the Federal Aviation Administration (FAA), should be used when operating in U.S. airspace.
5. Unsafe performance or conditions related to data link operations which potentially could affect continued safe operations in U.S. Airspace, (a data link event), should be reported to the FAA within 10 days of the time that such a hazard is identified.
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Appendix 4 APPENDIX 4. ACRONYMS AND ABBREVIATIONS 14 CFR Title 14 of The Code of Federal Regulations AC Advisory Circular ACARS Aircraft Reporting and Communications System ACO Aircraft Certification Office ACP Actual Communications Performance AD Airworthiness Directive ADS Automatic Dependent Surveillance ADS-C Automatic Dependent Surveillance-Contract AEG Aircraft Evaluation Group AFM Aircraft Flight Manual AFS Flight Standards Service AIM Aeronautical Information Manual AIP Aeronautical Information Publication AOC Aeronautical/Airline Operational Control ASRS Aviation Safety Reporting System ATC Air Traffic Control ATIS Automated Terminal Information Service ATM Air Traffic System Management ATN Aeronautical Telecommunication Network ATN B1 Aeronautical Teleco mmunication Network Baseline 1 ATP Air Traffic Procedures Service ATS Air Traffic Service CAA Civil Aviation Authority CBI Computer-Based Instruction CFR Code of Federal Regulations CHDO Certificate-Holding District Office CMO Certificate Management Office CNS Communications, Navigation, and Surveillance CPDLC Controller Pilot Data Link Communication CRM Crew Resource Management CSP Communication Service Provider D-ATIS Digital Automated Terminal Information System DCPC Direct Contro ller Pilot Communication DDG Dispatch Deviation Guide DDTC Digital Delivery of Expected Taxi Clearance DFDR Digital Flight Data Recorder DL Data Link ECAM Electronic Centralized Aircraft Monitoring EFIS Electronic Flight Instrument System EICAS Engine Indicating a nd Crew Alerting System EUROCAE European Organization for Civil Aviation Equipment FAA Federal Aviation Administration FANS Future Air Navigation System FIG Fans Inoperability Group** FIR Flight Information Region Page 1
Appendix 3 Page 1 (and 2) FIT Fans Inoperability Team FMC Flight Management Computer FMS Flight Management System FOEB Flight Operation Evaluation Board FOM Fans Operations Manual FSB Flight Standardization Board FSDO Flight Standards District Office G/TWIS Graphics/Text Weather Server GNSS Global Navigation Satellite System HF High Frequency (radio) HFDL High Frequency Data Link HMI Human Machine Interaction ICAO International Ci vil Aviation Organization IFO International Field Office INTEROP Interoperability Requirements Standards LOA Letter of Authorization LOFT Line-Oriented Flight Training MASPS Minimum Aviation System Performance Standard MEL Minimum Equipment List MMEL Master Minimum Equipment List MNPS Minimum Navigation Performance Specification MRB Maintenance Review Board MSecs Management Specifications NAS National Airspace System NAT North Atlantic Tracks NM Nautical Mile NMAC Near Mid-Air Collision NOTAM Notices to Airmen NSET National Simulator Evaluation Team OCD Oceanic Clearance Delivery OE Operating Experience OpSpecs Operation Specifications PAI Principal Avionics Inspector PANS Procedures for Air Navigation Service Part 91K Part 91 Subpart K PC Proficiency Check PDC Pre-Departure Clearance PI Principal Inspector PMI Principal Maintenance Inspector POI Principal Operations Inspector PT Proficiency Training R/AFM Rotorcraft/Airplane Flight Manual RCP Required Communication Performance RF Radio Frequency RNP Required Navigation Performance RSP Required Surveillance Performance
Appendix 4 RTCA Radio Technical Commission for Aeronautics SARPS Standards and Recommended Practices SATCOM Satellite Communication SDR Service Difficulty Report SPR Software Problem Report STC Supplemental Type Certificate TC Type Certificate TCPM Training Center Program Manager TSO Technical Standard Order TWIP Terminal Weather Information for Pilots VDL Vhf Data Link VHF Very High Frequency (radio) Page 1
Appendix 5 APPENDIX 5. APPLICATION AND TRAINING GUIDANCE
1. The operator’s application to obtain authorization to use data link must address and contain the following subjects including those identified in this advisory circular (AC). The applicable AC 120-70B paragraphs are referenced below.
a. List of Source Documents Used:
(1) For generic data link Operations (e.g., aircraft/avionics manufacturer documents)
(2) For area of operations specific policy/procedures. See “d” below
b. Description. Description of aircraft data link systems including certification documents and current configuration (e.g., current avionics load).
c. General Information.
d. Area of Operations/Routes Where Operator Intends to Use Data Link.
(1) List of areas and/or routes where operator intends to conduct data link operations.
(2) List of air traffic centers/service providers with which operator intends to communicate via data link.
(3) List policy/procedures source documents applicable to each area(s) of operations, such as:
(a) Operations manuals for specific areas of operations (e.g., Future Air Navigation System (FANS) Operations Manual (FOM) for operation in Asia Pacific FIR’s).
(b) State Aeronautical Information Publications (AIP).
(c) State Notices to Airmen (NOTAM).
(d) FAA chart supplements (e.g., Pacific and Alaska Chart Supplement).
e. Flightcrew Qualification Programs.
f. Manuals and Other Publications.
g. MMEL/MEL.
h. Issues Unique to a Particular Operator.
i. Maintenance Programs.
2. Content of Flightcrew Qualification Programs.