support of the DHS, the DOD, or other Federal security elements in the interest of national security. Such security services are only applicable within designated areas. ATC security services do not include ATC basic radar services or flight following. 

ATC SECURITY SERVICES POSITION- The position responsible for providing ATC security services as defined. This position does not provide ATC, IFR separation, or VFR flight following services, but is responsible for providing security services in an area comprising airspace assigned to one or more ATC operating sectors. This position may be combined with control positions. 

ATC SECURITY TRACKING- The continuous tracking of aircraft movement by an ATC facility in support of the DHS, the DOD, or other security elements for national security using radar (i.e., radar tracking) or other means (e.g., manual tracking) without providing basic radar services (including traffic advisories) or other ATC services not defined in this section. 

ATS SURVEILLANCE SERVICE [ICAO]– A term used to indicate a service provided directly by means of an ATS surveillance system. 

ATC SURVEILLANCE SOURCE– Used by ATC for establishing identification, control and separation using a target depicted on an air traffic control facility's video display that has met the relevant safety standards for operational use and received from one, or a combination, of the following surveillance sources: 

a. Radar (See RADAR.) 

b. ADS-B (See AUTOMATIC DEPENDENT SURVEILLANCE-BROADCAST.) 

c. WAM (See WIDE AREA MULTILATERATION.) 

(See INTERROGATOR.) (See TRANSPONDER.) (See ICAO term RADAR.) (Refer to AIM.) 

ATS SURVEILLANCE SYSTEM [ICAO]– A generic term meaning variously, ADS-B, PSR, SSR or any comparable ground-based system that enables the identification of aircraft. 

Note: A comparable ground-based system is one that has been demonstrated, by comparative assessment or other methodology, to have a level of safety and performance equal to or better than monopulse SSR. 

ATCAA- 

(See ATC ASSIGNED AIRSPACE.) 

ATCRBS- 

(See RADAR.) 

ATCSCC- 

(See AIR TRAFFIC CONTROL SYSTEM COMMAND CENTER.) 

ATCT- 

(See TOWER.) 

ATD- 

(See ALONG-TRACK DISTANCE.) 

ATIS- 

(See AUTOMATIC TERMINAL INFORMATION SERVICE.) 

ATIS [ICAO]- 

(See ICAO Term AUTOMATIC TERMINAL INFORMATION SERVICE.) 

ATS ROUTE [ICAO]- A specified route designed for channeling the flow of traffic as necessary for the provision of air traffic services. 

Note: The term “ATS Route” is used to mean variously, airway, advisory route, controlled or uncontrolled route, arrival or departure, etc. 

ATTENTION ALL USERS PAGE (AAUP)- The AAUP provides the pilot with additional information relative to conducting a specific operation, for example, PRM approaches and RNAV departures. 

AUTOLAND APPROACH-An autoland system aids by providing control of aircraft systems during a precision instrument approach to at least decision altitude and possibly all the way to touchdown, as well as in some cases, through the landing rollout. The autoland system is a sub-system of the autopilot system from which control surface management occurs. The aircraft autopilot sends instructions to the autoland system and monitors the autoland system performance and integrity during its execution. 

AUTOMATED EMERGENCY DESCENT- 

(See EMERGENCY DESCENT MODE.) 

AUTOMATED INFORMATION TRANSFER (AIT)- A precoordinated process, specifically defined in facility directives, during which a transfer of altitude control and/or radar identification is accomplished without verbal coordination between controllers using information communicated in a full data block. 

