Definition

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.

  Definition

A Division is defined as a group of members that are officially recognized by POSCON for the purpose of conducting certain special aviation-related activities on the Positive Control Network such as:

• Regional air traffic control services
• Specialty pilot activities

When there is an operational need, Divisions can be further divided into Sub-Divisions in order to focus the specialization.

  Definition

DA(H) is a specified minimum altitude in an instrument approach procedure by which a missed approach must be initiated if the required visual reference to continue the approach has not been established. The ‘altitude’ value is typically measured by a barometric altimeter; the ‘height’ value (H) is typically a radio altitude equivalent height above the touchdown zone (HAT) used only for advisory reference and does not necessarily reflect actual height above underlying terrain. [This definition is consistent with both current U.S. operator usage and ICAO international agreements.]

  Definition

For purposes of noise compliance rules, dual-certificated airplanes are those that are certificated to operate in either a Stage 2 or Stage 3 configuration. The only airplanes dual certificated by the FAA were certain Boeing 747’s, -300 series or earlier. For noise compliance purposes, these airplanes are considered Stage 2 unless the operator gets a supplemental type certificate to make the airplane Stage 3 only, or unless the operator voluntarily limits the operation to Stage 3 only.