aircraft on the runway, terminal or center area  saturation, weather below landing minimums, etc.  (See EXPECT FURTHER CLEARANCE (TIME).)  DELAY TIME- The amount of time that the arrival  must lose to cross the meter fix at the assigned meter  fix time. This is the difference between ACLT and  VTA.  DEPARTURE CENTER- The ARTCC having  jurisdiction for the airspace that generates a flight to  the impacted airport.  DEPARTURE CONTROL- A function of an  approach control facility providing air traffic control  service for departing IFR and, under certain  conditions, VFR aircraft.  (See APPROACH CONTROL FACILITY.)  (Refer to AIM.)  DEPARTURE SEQUENCING PROGRAM- A  program designed to assist in achieving a specified  interval over a common point for departures.  DEPARTURE TIME- The time an aircraft becomes  airborne.  DESCEND VIA– An abbreviated ATC clearance that  requires compliance with a published procedure  lateral path and associated speed restrictions and  provides a pilot-discretion descent to comply with  published altitude restrictions.  DESCENT SPEED ADJUSTMENTS- Speed decel- eration calculations made to determine an accurate  VTA. These calculations start at the transition point  and use arrival speed segments to the vertex.  DESIGNATED COMMON TRAFFIC ADVISORY  FREQUENCY (CTAF) AREA- In Alaska, in  addition to being designated for the purpose of  carrying out airport advisory practices while  operating to or from an airport without an operating  airport traffic control tower, a CTAF may also be  designated for the purpose of carrying out advisory  practices for operations in and through areas with a  high volume of VFR traffic.  a.  True- A predetermined desired course direction  to be followed (measured in degrees from true north).  b.  Magnetic- A predetermined desired course  direction to be followed (measured in degrees from  local magnetic north).  DIGITAL TERMINAL AUTOMATION SYSTEM  (DTAS)- A system where digital radar and beacon  data is presented on digital displays and the  operational program monitors the system perfor- mance on a real-time basis.  DIGITAL TARGET- A computer-generated symbol  representing an aircraft's position, based on a primary  return or radar beacon reply, shown on a digital  display.  DIGITAL-AUTOMATIC TERMINAL INFORMA- TION SERVICE (D-ATIS)- The service provides  text messages to aircraft, airlines, and other users  outside the standard reception range of conventional  ATIS via landline and data link communications to  the cockpit. Also, the service provides a computer- synthesized voice message that can be transmitted to  all aircraft within range of existing transmitters. The  Terminal Data Link System (TDLS) D-ATIS  application uses weather inputs from local automated  weather sources or manually entered meteorological  data together with preprogrammed menus to provide  standard information to users. Airports with D-ATIS  capability are listed in the Chart Supplement U.S.  DESIRED TRACK- The planned or intended track  between two waypoints. It is measured in degrees  from either magnetic or true north. The instantaneous  angle may change from point to point along the great  circle track between waypoints.  DETRESFA (DISTRESS PHASE) [ICAO]- The  code word used to designate an emergency phase  wherein there is reasonable certainty that an aircraft  and its occupants are threatened by grave and  imminent danger or require immediate assistance.  a.  A departure from a current clearance, such as an  off course maneuver to avoid weather or turbulence.  b.  Where specifically authorized in the CFRs and  requested by the pilot, ATC may permit pilots to  deviate from certain regulations.  DH- (See DECISION HEIGHT.)  DH [ICAO]- (See ICAO Term DECISION ALTITUDE/  DECISION HEIGHT.)  DEVIATIONS- DESIRED COURSE- DIGITIZED TARGET- A computer-generated  indication shown on an analog radar display resulting  from a primary radar return or a radar beacon reply.  PCG D-2  8/15/19  Pilot/Controller Glossary 