example, the SBS ground system provides ADS-R service to rebroadcast UAT messages on 1090 MHz and vice versa.
ADS-B Traffic Advisory System (ATAS). An ADS-B In application that augments flight crew traffic situation awareness in support of the see-and-avoid responsibility by providing alerts of traffic that are detected in conflict with ownship. This application is named Traffic Situation Awareness with Alerts (TSAA) in RTCA DO-317B.
Availability. An indication of the ability of a system or subsystem to provide usable service. Availability is expressed in terms of the probability of the system or subsystem being available at the beginning of an intended operation.
Basic Airborne (AIRB). The basic airborne situation awareness application enhances the flight crew’s traffic situation awareness through the provision of an on-board graphical display of surrounding traffic that transmits ADS-B data of a sufficient quality. Pilots will use the CDTI to supplement and enhance out-the-window visual acquisition and listening to radio communications.
Caution. The level or category of alert for conditions that require immediate flight crew awareness and subsequent flight crew response.
Coast Interval. The elapsed time since a report from any source has been correlated with the track.
Cockpit Display of Traffic Information (CDTI). The pilot interface portion of the Aircraft Surveillance Applications System. This interface includes traffic display(s) and all the controls that interact with such a display. At a minimum, CDTI includes a graphical plan-view (top down) traffic display. Additional graphical and non-graphical display surfaces may also be included. The CDTI receives position information of traffic and Ownship from the airborne surveillance and separation assurance processing (ASSAP) function. The ASSAP receives such information from the surveillance sensors and Ownship position sensors.
CDTI Assisted Visual Separation (CAVS). The CDTI is used to assist the flight crew in acquiring and maintaining visual contact during visual separation on approach. The CDTI is also used in conjunction with visual, out-the-window contact to follow the preceding aircraft during the approach. The application is expected to improve both the safety and the performance of visual separation on approach. It may allow for the continuation of visual separation on approach even if visual contact out-the-window is momentarily lost.
Conformal. A desirable property of map projections. A map projection (a function that associate points on the surface of an ellipsoid or sphere representing the earth to points on a flat surface such as the CDTI display) is said to be conformal if the angle between any two curves on the first surface is preserved in magnitude and sensed by the angle between the corresponding curves on the other surface.
Correlation. The process of determining that a new measurement belongs to an existing track.
Controller Pilot Data Link Communication (CPDLC). Provides direct data communication between the pilot and the air traffic controller through a data link.
Data Block. A block of information about selected traffic that is displayed somewhere around the edge of the CDTI display, rather than mixed in with the symbols representing traffic in the main part of the display.
Data Tag. A block of information that is displayed next to the traffic symbol in the main part of the CDTI display.
Designated Application. An application that operates only on specifically-chosen (either by the flight crew or automation) traffic. They generally operate only for a specific flight operation.
Designated Traffic. Traffic upon which a designated application is to be conducted.
Desirable. The capability denoted as desirable is not required to perform the procedure, but would increase the utility of the operation.
Direct Controller Pilot Communication (DCPC). Direct communication established between the controller and the pilot without having to relay through another unit or going through a secondary means of delivery for that information. Currently, this is accomplished by conventional voice radio operations or CPDLC.
Differential Ground Speed. Calculated by taking the difference between the magnitude of the ownship ground speed and the designated traffic ground speed. The assumption is that ownship is following the designated traffic approach path over the ground. Positive values indicate closure on the designated traffic.
Display Range. The maximum distance from own-ship that is represented on the CDTI display. If the CDTI display is regarded as a map, then longer display ranges correspond to smaller map scales, and short display ranges correspond to larger map scales.
Enhanced Visual Acquisition (EVAcq). This application is an enhancement for the out the-window visual acquisition of aircraft traffic and potentially ground vehicles.
Estimation. The process of determining a track’s state based on new measurement information.
Extended Squitter. A long (112 bit) Mode S transmission that is spontaneously produced by the radio as opposed to a response to a Mode S Interrogation. Extended Squitter is the mechanism used to provide ADS-B messages from a Mode S transponder.
Extrapolation. The process of predicting a track’s state forward in time based on the track’s last kinematic state.
Field of View. The field of view of a CDTI is the geographical region within which the CDTI shows traffic. Some documents call this the field of regard.
Flight Information Service Broadcast (FIS-B). FIS-B is a ground broadcast service provided over the UAT data link. The FAA FIS-B system provides pilots and flight crews of properly equipped aircraft with a cockpit display of certain aviation weather and aeronautical information.
Flight Crew. One or more cockpit crew members required for the operation of the aircraft.
Ground Speed. The magnitude of the horizontal velocity vector (see velocity). In these minimum operational performance standards (MOPS) it is always expressed relative to a frame of reference that is fixed with respect to the earth’s surface such as the WGS-84 ellipsoid.
Ground Track Angle. The direction of the horizontal velocity vector (see velocity) relative to the ground as noted in ground speed.
Hazard Classification. Refer to AC 25-1309-1(), System Design and Analysis, or AC 23.1309-1(), System Safety Analysis and Assessment for Part 23 Airplanes, as applicable.
Horizontal Velocity. The component of velocity in a local horizontal plane. For Global Positioning System (GPS) sensors, that plane is tangent to the WGS-84 ellipsoid and is vertically displaced such that it contains the navigation sensors’ reference point. For inertial navigation system (INS) equipment, the local plane is perpendicular to the local gravity vector.
International Civil Aviation Organization (ICAO). A United Nations organization that is responsible for developing international standards, and recommending practices, and procedures covering a variety of technical fields of aviation.
In-Trail Procedure (ITP). A procedure that allows an aircraft to climb-through or descend-through another aircraft’s altitude in order to make a desired flight level change.
Latency. The time incurred between two particular interfaces. Total latency is the delay between the time of a measurement and the time that the measurement is reported at a particular interface (the latter minus the former). Components of the total latency are elements of the total latency allocated between different interfaces. Each latency component will be specified by naming the interfaces between which it applies.
Nautical Mile (NM). A unit of length used in the fields of air and marine navigation. In this document, a nautical mile is always the international nautical mile of 1852 m exactly.
Own-ship. From the perspective of a flight crew, or of the ASSAP and CDTI functions used by that flight crew, the own-ship is the ASA participant (aircraft or vehicle) that carries that flight crew and those ASSAP and CDTI functions.
Pressure Altitude. Altitude reported by a barometric pressure altimeter without corrections for local pressure settings.
Primary Surveillance Radar (PSR). A radar sensor that listens for the echoes of pulses that it transmits to illuminate aircraft targets. PSR sensors, in contrast to secondary surveillance radar (SSR) sensors, do not depend on the carriage of transponders on board the aircraft targets.
Range Reference. The CDTI feature of displaying range rings or other range markings at specified radii from the own-ship symbol.
Reference Aircraft. An aircraft within the ITP geometric criteria for usage as reference when requesting an ITP clearance.
Secondary Surveillance Radar (SSR). A radar sensor that listens to replies sent by transponders carried on board airborne targets. SSR sensors, in contrast to primary surveillance radar (PSR) sensors, require the aircraft under surveillance to carry a transponder.
Selected Traffic. Traffic for which additional information is requested by the flight crew.
Sensor. A measurement device. An air data sensor measures atmospheric pressure and temperature, to estimate pressure altitude, and pressure altitude rate, airspeed, etc. A primary surveillance radar sensor measures its antenna direction and the times of returns of echoes of pulses that it transmits to determine the ranges and bearings of airborne targets.
A secondary surveillance radar sensor measures its antenna direction and the times of returns of replies from airborne transponders to estimate the ranges and bearings of airborne targets carrying those transponders.
Separation. The minimum distance between aircraft/vehicles allowed by regulations.
Separation requirements vary by factors such as radar coverage (none, single, composite), domain (terminal, en route, oceanic), and flight rules (instrument or visual).
Simple Action. A flight crew action that may be performed within a short period of time and without requiring significant concentration that would distract from the main aviation tasks (e.g., a button press). Please refer to AC 25-11( ) for more details.
Spacing. A distance maintained from another aircraft for specific operations.
State Vector. An aircraft’s current horizontal position, vertical position, horizontal velocity, vertical velocity, and navigational accuracy and integrity.
SURF (Basic Surface). An ADS-B application that displays traffic over an airport surface map underlay, and is used to support the flight crew in making decisions about taxiing, takeoff, and landing. The underlying map may depict runways only, or runways, taxiways, and other movement areas.
Traffic Selection. Manual process of flight crew selecting a traffic element.
TCAS Potential Threat. Traffic detected by TCAS equipment on board the own-ship, that has met the Potential Threat classification criteria for a TCAS TA and does not meet the Threat Classification criteria for a TCAS RA (RTCA/DO-185B § 1.8). If the ASAS own - ship CDTI display is also used as a TCAS TA display, then information about TCAS potential threats will be conveyed to the CDTI via the ASSAP function.
TCAS Proximate Traffic. Traffic, detected by TCAS equipment on board the own-ship, that is within 1200 feet vertically and 6 NM horizontally of the own-ship (RTCA/DO-185B § 1.8). If the ASA system own-ship CDTI display is also used as a TCAS display, then information about TCAS proximate traffic will be conveyed to the CDTI, possibly via the ASSAP function.
TCAS-Only Traffic. A traffic element about which TCAS has provided surveillance information, but which the ASSAP function has not correlated with traffic from other surveillance sources such as ADS-B, ADS-R, or TIS-B.
Time of Applicability. The time that a particular measurement or parameter is (or was) relevant.
Track. (1) A sequence of reports from the ASSAP function that all pertain to the same traffic target. (2) Within the ASSAP function, a sequence of estimates of traffic target state that all pertain to the same traffic element.
Track Angle. See Ground Track Angle.
Track State. See State Vector.
Traffic. All aircraft/vehicles that are within the operational vicinity of own-ship.
Traffic Element. An aircraft or vehicle.
Traffic Information Service – Broadcast (TIS-B). A surveillance service that broadcasts traffic information derived from one or more ground surveillance sources to suitably equipped aircraft or surface vehicles, with the intention of supporting ASA applications.
Traffic Symbol. A depiction on the CDTI display of an aircraft or vehicle other than the own-ship.
Transponder. A piece of equipment carried on board an aircraft to support the surveillance of that aircraft by secondary surveillance radar sensors. A transponder receives interrogation signals on 1030 MHz and replies on the 1090 MHz downlink frequency.
Traffic-To-Follow. A term used for CAVS which is used to refer to the aircraft preceding ownship.
Universal Access Transceiver (UAT). A wideband multipurpose data link intended to operate globally on a single channel with a channel signaling rate of just over 1Mbps. By design, UAT supports multiple broadcast services including FIS-B and TIS-B in addition to ADS-B. This is accomplished using a hybrid medium access approach that incorporates both time-slotted and random unslotted access.
Visual Separation on Approach (VSA). The CDTI is used to assist the flight crew in acquiring and maintaining visual contact during visual separation on approach. The CDTI is also used in conjunction with visual, out-the-window contact to follow the preceding aircraft during the approach. The application is expected to improve both the safety and the performance of visual separation on approach. It may allow for the continuation of visual separation on approach when they otherwise would have to be suspended due to the difficulty of visually acquiring and tracking the other preceding aircraft.
Velocity. The rate of change of position. Horizontal velocity is the horizontal component of velocity and vertical velocity is the vertical component of velocity.
Warning. The level or category of alert for conditions that require immediate flight crew awareness and immediate flight crew response.
2. Acronyms.
AC Advisory Circular (FAA) ADS-B Automatic Dependent Surveillance – Broadcast ADS-R Automatic Dependent Surveillance – Rebroadcast AFM Aircraft Flight Manual AIRB Basic Airborne AML Approved Model List ASA Aircraft Surveillance Applications ASAS Aircraft Surveillance Applications System ASSAP Airborne Surveillance and Separation Assurance Processing ASTC Amended Supplemental Type Certificate ATAS ADS-B Traffic Advisory System ATC Air Traffic Control ATCRBS Air Traffic Control Radar Beacon System ATS Air Traffic Services CDTI Cockpit Display of Traffic Information CAVS CDTI Assisted Visual Separation CFR Code of Federal Regulations CPDLC Controller Pilot Data Link Communication DCPC Direct Controller Pilot Communication EFIS Electronic Flight Instrument System EUROCAE European Organization for Civil Aviation Equipment EVAcq Enhanced Visual Acquisition FAA Federal Aviation Administration FIS-B Flight Information Services - Broadcast fpm Feet Per Minute ft Feet GNSS Global Navigation Satellite System GPS Global Positioning System ICAO International Civil Aviation Organization ID Identification 42
IFR Instrument Flight Rules ITP In-Trail Procedure kts Knots m meter (or “metre”), the SI metric system base unit for length MCDU Multi-Function Control and Display Unit MFD Multi-Function Display MHz Mega Hertz MOPS Minimum Operation Performance Standards (RTCA documents) N/A Not Applicable or No Change RA Resolution Advisory (TCAS II) RC Radius of Containment s second, the SI metric system base unit for time or time interval SAE Society of Automotive Engineers SBS Surveillance and Broadcast Services SC Special Committee SURF Basic Surface Situation Awareness TA Traffic Advisory (TCAS II) TAS Traffic Advisory System TCAS Traffic Alert and Collision Avoidance System TCAS I TCAS system that does not provide resolution advisories TCAS II TCAS system that provides resolution advisories TIS-B Traffic Information Service – Broadcast TSO Technical Standard Order UAT Universal Access Transceiver VSA Visual Separation on Approach WGS-84 World Geodetic System-1984 43
Appendix E Related Documents
1. FAA Documents.
AC 20-140( ), Guidelines for Design Approval of Aircraft Data Link Communication Systems Supporting Air Traffic Services (ATS).
AC 20-149 ( ), Installation Guidance for Flight Information Service Broadcast (FIS-B)
AC 20-151(), Airworthiness Approval of Traffic Alert and Collision Avoidance Systems
(TCAS II), Versions 7.0 & 7.1 and Associated Mode S Transponders AC 20-165(), Airworthiness Approval of Automatic Dependent Surveillance - Broadcast (ADS-B) Out Systems.
AC 20-165 ( ), Airworthiness Approval of Automatic Dependent Surveillance Broadcast (ADS-B) Out Systems AC 20-175 ( ), Controls for Flight Deck Systems.
AC 23.1309-1( ), System Safety Analysis and Assessment for Part 23 Airplanes.
AC 23.1311-1( ), Installation of Electronic Display in Part 23 Airplanes.
AC 25-11( ), Electronic Flight Displays.
AC 25.1302-1( ), Installed Systems and Equipment for Use by the Flightcrew.
AC 25-1309-1( ), System Design and Analysis.
AC 25.1322-1( ), Flightcrew Alerting AC 27-1( ), Certification of Normal Category Rotorcraft.
AC 29-2( ), Certification of Transport Category Rotorcraft.
AC 90-114( ), Automatic Dependent Surveillance-Broadcast (ADS-B) Operations.
AC 120-55 ( ), Air Carrier Operational Approval and Use of TCAS II
TSO-C118 ( ), Traffic Alert And Collision Avoidance System (TCAS) Airborne Equipment, TCAS- I.
TSO-C119( ),Traffic Alert and Collision Avoidance System (TCAS) Airborne Equipment, TCAS II With Optional Hybrid Surveillance.
TSO-C129( ), Airborne Supplemental Navigation Equipment Using the Global Positioning System (GPS).
TSO-C145( ), Airborne Navigation Sensors Using the Global Positioning System (GPS) Augmented by the Wide Area Augmentation System (WAAS).
TSO-C146( ), Stand-Alone Airborne Navigation Equipment Using the Global Positioning System (GPS) Augmented by the Wide Area Augmentation System (WAAS).
TSO-C147( ), Traffic Advisory System (TAS) Airborne Equipment.
TSO-C154c, Universal Access Transceiver (UAT) Automatic Dependent Surveillance Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz.
TSO-C165a( ), Electronic Map Display Equipment for Graphical Depiction of Aircraft Position.
TSO-C166b, Extended Squitter Automatic Dependent Surveillance - Broadcast (ADS-B) and Traffic Information Service - Broadcast (TIS-B) Equipment Operating on the Radio Frequency of 1090 Megahertz (MHz).
TSO-C195( ), Avionics Supporting Automatic Dependent Surveillance - Broadcast (ADS-B) Aircraft Surveillance Applications (ASA).
TSO-C196( ), Airborne Supplemental Navigation Sensors for Global Positioning System Equipment Using Aircraft-Based Augmentation.
2. RTCA, Inc. (RTCA DO) Documents:
RTCA/DO-160, Environmental Conditions and Test Procedures for Airborne Equipment RTCA/DO-178C, Software Considerations in Airborne Systems and Equipment Certification.
RTCA/DO-185, Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance System II (TCAS II) Airborne Equipment RTCA/DO-208, Minimum Operational Performance Standards for Airborne Supplemental Navigation Equipment Using Global Positioning System (GPS).
RTCA/DO-229D, Minimum Operational Performance Standards for Global Positioning System/Wide Area Augmentation System Airborne Equipment.
RTCA/DO-247, The Role of the Global Navigation Satellite System (GNSS) in Supporting Airport Surface Operations.
RTCA/DO-254, Design Assurance Guidance for Airborne Electronic Hardware.
RTCA/DO-257A, Minimum Operational Performance Standards for the Depiction of Navigational Information on Electronic Maps.
RTCA/DO-260B, Minimum Operational Performance Standards for 1090 MHz Automatic Dependent Surveillance-Broadcast (ADS-B).
RTCA/DO-282B, Minimum Operational Performance Standards for Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B).
RTCA/DO-306, Change 1. Safety and Performance Standard for Air Traffic Data Link Services in Oceanic and Remote Airspace (Oceanic SPR Standard).
RTCA/DO-316, Minimum Operational Performance Standards (MOPS) for Global Positioning System/Aircraft Based Augmentation System Airborne Equipment.
RTCA/DO-317B, Minimum Operational Performance Standards (MOPS) For Aircraft Surveillance Applications System (ASAS).
3. ARINC Documents:
ARINC 718A, Mark 4 Air Traffic Control Transponder (ATCRBS/MODE S).
ARINC 735B, Mark 2 Traffic Alert and Collision Avoidance System (TCAS).
ARINC 738A, Air Data and Inertial Reference System (ADRS).
ARINC 743A, GNSS Sensor.
4. SAE Documents.
SAE ARP 4754A, Guidelines for Development of Civil Aircraft Systems.
SAE ARP 4761, Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment.
5. How to Get Related Documents:
a. You can get copies of the 14 CFR parts referenced in this AC online from the GPO electronic CFR Internet website at www.gpoaccess.gov/cfr/.
b. Order copies of RTCA documents from RTCA Inc., 1150 18th St. NW, Suite 910, Washington, D.C. 20036. For general information, telephone (202) 833-9339 or fax (202) 833 9434. You can also order copies online at http:/www.rtca.org.
c. Order copies of ARINC documents from ARINC Incorporated, 2551 Riva Rd., Annapolis, MD, 21401. Telephone 1-800-633-6882, fax (410)-956-5465.
You can also get copies from their website at www.arinc.com.
d. Order copies of SAE documents from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, telephone (724) 776-4970, fax (724) 776-0790. Also, order copies online at www.sae.org.
e. 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 http://www.faa.gov/regulations_policies/advisory_circulars/ or www.airweb.faa.gov/rgl.