Aviation Maintenance Terms beginning with D

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.

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.

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.

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.