Appendix F Message Element Justification UM138 CONFIRM TIME OVER REPORTED WAYPOINT. Use of ADS-C is recommended.
UM139 CONFIRM REPORTED WAYPOINT Use of ADS-C is recommended.
UM140 CONFIRM NEXT WAYPOINT Use of ADS-C is recommended.
UM141 CONFIRM NEXT WAYPOINT ETA. Use of ADS-C is recommended.
UM142 CONFIRM ENSUING WAYPOINT Use of ADS-C is recommended.
UM146 REPORT GROUND TRACK Use of ADS-C is recommended.
UM181 REPORT DISTANCE (to/from) (position) Use of ADS-C is recommended.
UM145 CONFIRM HEADING Use of ADS-C is recommended.
UM177 AT PILOTS DISCRETION Not globally accepted. In airspace managed by the United States, when the controller issues UM177 AT PILOTS DISCRETION in conjunction with altitude assignments, the associated instruction to climb or descend may be executed when convenient and at any preferred rate. The aircraft may temporarily maintain intermediate levels but once the aircraft has vacated a level it may not return to that level.
F-56
Appendix F Table F-30. FANS 1/A Downlink Messages Not Recommended for Use Message Element Justification DM69 REQUEST VMC DESCENT Avoid use of this message element due to potential misinterpretation DM75 AT PILOTS DISCRETION Avoid use of this message element due to potential misinterpretation DM 67 ‘WHEN CAN WE EXPECT DESCENT TO (altitude)’ Avoid use of this message due to potential misinterpretation of subsequent response. Use of LVLD-6 WHEN CAN WE EXPECT LOWER LEVEL and LVLD-7 WHEN CAN WE EXPECT HIGHER LEVEL is recommended.
DM67 ‘WHEN CAN WE EXPECT CLIMB TO (altitude)’ Avoid use of this message due to potential misinterpretation of subsequent response. Use of LVLD-6 WHEN CAN WE EXPECT LOWER LEVEL and LVLD-7 WHEN CAN WE EXPECT HIGHER LEVEL is recommended.
DM74 REQUEST TO MAINTAIN OWN SEPARATION AND VMC Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM8 REQUEST CRUISE CLIMB TO (altitude) Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM54 WHEN CAN WE EXPECT CRUISE CLIMB TO (altitude) Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM72 REACHING (altitude) Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM79 ATIS (ATIS code) Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM67 ‘MONITORING (unit name) (frequency)’ Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM16 AT (position) REQUEST OFFSET (specified distance) (direction) OF ROUTE Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM17 AT (time) REQUEST OFFSET (specified distance) (direction) OF ROUTE Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM26 REQUEST WEATHER DEVIATION TO (position) VIA (route clearance) Not operationally required.
Note: These messages have been excluded from future B2 implementation.
DM33 PRESENT POSITION (position) Use of ADS-C is recommended.
DM36 PRESENT GROUND TRACK (degrees) Use of ADS-C is recommended.
F-57
Appendix F Message Element Justification DM42 NEXT WAYPOINT (position) Use of ADS-C is recommended.
DM43 NEXT WAYPOINT ETA (time) Use of ADS-C is recommended.
DM44 ENSUING WAYPOINT (position) Use of ADS-C is recommended.
DM45 REPORTED WAYPOINT (position) Use of ADS-C is recommended.
DM46 REPORTED WAYPOINT (time) Use of ADS-C is recommended.
DM78 AT (time) (distance) (to/from) (position) Use of ADS-C is recommended.
DM32 PRESENT ALTITUDE (altitude) Use of ADS-C is recommended.
DM35 PRESENT HEADING (degrees) Use of ADS-C is recommended.
DM19 REQUEST (speed) TO (speed) Use of SPDD-1 REQUEST (speed) is recommended.
DM50 WHEN CAN WE EXPECT (speed) TO (speed) Use of SPDD-1 REQUEST (speed) is recommended.
Table F-31. ATN B1 Uplink Messages Not Recommended for Use Message Element Justification UM165 THEN Avoid use of this message element due to potential misinterpretation.
Table F-32. ATN B1 Downlink Messages Not Recommended for Use Message Element Justification DM89 MONITORING (unit name) (frequency) Not operationally required.
Note: This message has been excluded from future B2 implementation.
F-58
Appendix G AP PENDIX G. TERMINOLOGY AND ACRONYMS G.
1 Terminology.
1. Aeronautical Telecommunications Network (ATN). A global inter-network architecture that allows ground, air-ground, and avionic data subnetworks to exchange digital data for the safety of air navigation and for the regular, efficient, and economic operation of Air Traffic Services (ATS).
2. Air Navigation Services Provider (ANSP). An organization responsible for the provision of ATS.
3. Air Traffic Data Link Service. A data communication capability comprising air/ground and ground/ground data network services, specified data link message sets and protocols, aircraft equipment, Air Traffic Service Unit (ATSU) facility equipment, and operational procedures intended to provide primary or supplemental ATSU communications.
4. Air Traffic Service Unit (ATSU). This domain includes the controller and the ATSU system which consists of an end system where data communications applications reside, a ground to ground router, a ground to ground communication network, and human-machine interface (HMI).
5. Aircraft Communications Addressing and Reporting System (ACARS). ACARS is a digital data link system for transmission of short messages between aircraft and ground stations via airband radio or satellite. ACARS as a term refers to the complete air and ground system, consisting of a service provider and aircraft/ground equipment.
6. Allocations. For approval, design, and monitoring purposes, performance requirements are provided against allocated human and technical Air Traffic System Management (ATM)/Communication, Navigation, and Surveillance (CNS) elements
(i.e., the aircraft system, aircraft operator, ANSP, and Communication Service Provider (CSP)) of the data communications transaction.
7. Automatic Dependent Surveillance-Contract (ADS-C). ADS-C is a surveillance information system using automated reports. An agreement is established between the ground system and the aircraft via a data link. Without pilot input, the ATSU can establish a “contract” to provide reports of aircraft position, altitude, speed, elements of navigational intent, and meteorological data. The system can generate the following types of reports:
• Demand: An ATSU can request an update as needed, and this does not affect an existing contact preset rate.
• Event: A change in vertical rate, lateral deviation, or altitude automatically triggers a report.
• Periodic: The ATSU can set or alter the update rate as needed (a higher update rate is usually required in high traffic areas or with reduced lateral separations).
G-1
Appendix G
8. Availability. The probability that an operational communication transaction can be initiated when needed.
9. Communication Transaction Time. The maximum time for the completion of the operational communication transaction, after which the initiator should revert to an alternative procedure.
10. Continuity. The probability that an operational communication transaction can be completed within the communication transaction time.
11. Controller-Pilot Data Link Communications (CPDLC). CPDLC is a two-way data-link communication system by which controllers can transmit digital text messages to an aircraft as an alternative to voice communications. Messages from an aircraft to the ATSU may follow a standard format or may be free text. Messages from a controller normally follow a standard format and usually require a response from the pilot.
12. Current Data Authority (CDA). The designated ground system through which a CPDLC dialogue between a pilot and a controller currently responsible for the flight is permitted to take place.
13. Data Link Communication System. A data link communication system is a means of transmitting and receiving digital information. “Data link” is a generic term that encompasses different types of data link communication systems and subnetworks.
14. Departure Clearance (DCL). DCL (CPDLC-DCL) is the initial phase of U.S. domestic airspace implementation of data communication and is limited to tower services. CPDLC-DCL provides automated assistance for requesting and delivering initial and revised DCLs using CPDLC. The DCL includes flight plan route, climb via and/or initial/requested altitude, beacon code assignment, and departure frequency.
15. Downlink Message (DM). A CPDLC message sent from an aircraft.
16. Future Air Navigation System (FANS). FANS is an avionics system which provides direct data link communication between the pilot and the air traffic controller. The communications include air traffic control (ATC) clearances, pilot requests, and Position Reporting (PR).
17. Integrity. The probability of one or more undetected errors in a completed communication transaction.
18. Maximum Accumulated Unplanned Outage Time. A value that defines the acceptable accumulated duration of unplanned outages that exceed the unplanned outage duration limit in a specified time period.
Note: Unplanned outages that are less than the unplanned outage duration limit are considered against the criterion for continuity.
G-2
Appendix G
19. Maximum Number of Unplanned Outages. A value that defines the acceptable number of unplanned outages that exceed the unplanned outage duration limit in a specified time period.
Note: Unplanned outages that are less than the unplanned outage duration limit are considered against the criterion for continuity.
20. Minimum Equipment List (MEL). A list which provides for the operation of aircraft, subject to specified conditions, with particular equipment inoperative, prepared by an operator in conformity with, or more restrictive than, the Master Minimum Equipment List (MMEL) established for the aircraft type.
21. Next Data Authority (NDA). The ground system so designated by the CDA through which an onward transfer of communications and control can take place.
22. Performance-Based Communication and Surveillance (PBCS). PBCS is a concept that applies required communication performance (RCP) and required surveillance performance (RSP) specifications to ensure appropriate performance levels for relevant ATM operations (e.g., application of a reduced separation minimum).
23. Pre-Departure Clearance (PDC). A PDC is a clearance that is issued in a text format rather than being issued audibly over a clearance delivery frequency. This text clearance is issued through the use of a data link communication computer system and is relayed from a dispatch system to the pilot via an ACARS message or a terminal gate printer.
24. Required Communication Performance (RCP). A set of requirements for ATS provision, aircraft capability, and operations needed to support performance-based communication within a defined airspace.
• RCP Availability - Aircraft (AAIR). An RCP allocation that specifies the required probability that the aircraft system is serviceable for the relevant communication capability.
• RCP Availability – CSP (ACSP). An RCP allocation that specifies the required probability that the CSP systems are available to provide the required level of communication service, given the ATSU’s system is available.
25. Required Surveillance Performance (RSP). A statement of the performance requirements for operational surveillance in support of specific ATM functions.
26. Satellite Communication (SATCOM). The Aviation SATCOM is a worldwide mobile communications system providing voice and data communications services between aircraft subnetworks and ground subnetworks.
27. Secondary Surveillance Radar (SSR). A type of radar used by ATSU to transmit and receive data on transponder equipped aircraft. This data includes barometric altitude and identification codes.
28. Supplemental Type Certificate (STC). An STC is a type certificate (TC) issued when an applicant has received FAA approval to modify an aeronautical product from its original design.
G-3
Appendix G
29. Surveillance Transaction Time. The surveillance transaction time specifies the maximum time for the completion of the operational surveillance process. This parameter is an indication of time criticality.
30. Type Certificate (TC). A TC is issued by the FAA when the airworthiness of an aircraft manufacturing design has been determined to be acceptable. Once issued, the design cannot be changed without approval from the FAA.
31. Uplink Message (UM). A CPDLC message sent from a ground system.
G-4
Appendix G G.2 Acronyms.
Acronym Meaning 4-D Four-Dimensional 4DTRAD Four-Dimensional Trajectory Data Link 14 CFR Title 14 of The Code of Federal Regulations AC Advisory Circular ACARS Aircraft Communications Addressing and Reporting System ACL Air Traffic Control Clearance ACM Air Traffic Control Communication Management ACP Actual Communications Performance ACTP Actual Communication Technical Performance AD Airworthiness Directive ADS Automatic Dependent Surveillance ADS-C Automatic Dependent Surveillance-Contract AEG Aircraft Evaluation Group AFM Airplane Flight Manual AFN Air Traffic Service Facilities Notification AIP Aeronautical Information Publication AIS Aeronautical Information Service AMC Air Traffic Control Microphone Check ANSP Air Navigation Service Provider AOC Aeronautical Operational Control ASP Actual Surveillance Performance ATC Air Traffic Control ATIS Automatic Terminal Information Service ATM Air Traffic System Management ATN Aeronautical Telecommunications Network ATN B1 Aeronautical Telecommunications Network Baseline 1 ATS Air Traffic Service ATSU Air Traffic Service Unit G-5
Appendix G Acronym Meaning B2 Baseline 2 CADS Centralized ADS-C System CDA Current Data Authority CDU Control Display Unit CFR Code of Federal Regulations CM Context Management CNS Communication, Navigation, and Surveillance CPDLC Controller-Pilot Data Link Communication CRA Central Reporting Agency CRD Clearance Request and Delivery CRM Crew Resource Management CSP Communication Service Provider CVR Cockpit Voice Recorder CWA Central Weather Advisory D-ATIS Digital Automatic Terminal Information Service D-TAXI Data Link Taxi DCL Departure Clearance DCNS Data Communications Network Service DLIC Data Link Initiation Capability DLMA Data Link Monitoring Agency DM Downlink Message DRNP Dynamic Required Navigation Performance DSC Downstream Clearance DT RSP Data Delivery Time (associated with nominal continuity – 95 percent) EPP Extended Projected Profile ERAM En Route Automation Modernization ET Expiration Time EUROCAE European Organization for Civil Aviation Equipment FAA Federal Aviation Administration FANS Future Air Navigation System G-6
Appendix G Acronym Meaning FBO Fixed-Base Operator FDR Flight Data Recorder FIR Flight Information Region FMS Flight Management System GA General Aviation GOLD Global Operational Data Link (GOLD) Manual (Doc 10037) GPS Global Positioning System HF High Frequency (radio) HFDL High Frequency Data Link HMI Human-Machine Interface ICAO International Civil Aviation Organization IER Information Exchange and Reporting IFO International Field Office IM Interval Management INTEROP Interoperability Requirements Standards ISPACG Informal South Pacific Air Traffic Services Coordinating Group ITP In-Trail Procedures LOA Letter of Authorization MEL Minimum Equipment List METI Meteorological Information MMEL Master Minimum Equipment List M/M/S Make, Model, and Series MOPS Minimum Operational Performance Standard MSpec Management Specification MTBO Mean Time Between Outages MU Management Unit NAT North Atlantic NDA Next Data Authority NM Nautical Mile NSDA National Single Data Authority G-7
Appendix G Acronym Meaning OCD Oceanic Clearance Delivery OCL Oceanic Clearance OEM Original Equipment Manufacturer OPR Operational Problem Report OpSpec Operations Specification OT RSP data overdue time (associated with operational continuity) PANS Procedures for Air Navigation Service Part 91K Part 91 Subpart K PBCS Performance-Based Communication and Surveillance PBN Performance-Based Navigation PDC Pre-Departure Clearance PI Principal Inspector PIREP Pilot Weather Report POI Principal Operations Inspector PORT Pilot Operational Response Time PR Position Reporting RA Radar Associate RCP Required Communication Performance RCP AAIR RCP Availability – Aircraft RCP ACSP RCP Availability – CSP RCP C RCP Continuity RCP I RCP Integrity RCTP Required Communication Technical Performance RF Radio Frequency RLatSM Reduced Lateral Separation Minima RMA Regional Monitoring Agency RNAV Area Navigation RNP Required Navigation Performance RSMP Required Surveillance Monitored Performance RSP Required Surveillance Performance G-8
Appendix G Acronym Meaning RSP AAIR RSP Availability – Aircraft RSP ACSP RSP Availability – CSP RSP C RSP Continuity RSP I RSP Integrity RSTP Required Surveillance Technical Performance RTF Radio Telephone SATCOM Satellite Communication SBB SwiftBroadband SBD Short Burst Data SDP Service Delivery Point SELCAL Selective-Calling System SID Standard Instrument Departure SIGMET Significant Meteorological Information SITA Société International de Télécommunications Aeronautiques SOC Statement of Compliance SPR Safety and Performance Requirements SSR Secondary Surveillance Radar STC Supplemental Type Certificate TC Type Certificate TDLS Tower Data Link Services TSO Technical Standard Order TWIP Terminal Weather Information for Pilots UM Uplink Message VDL Very High Frequency Data Link VHF Very High Frequency (radio) G-9