A portion of airspace, defined both vertically and laterally, that is under the control of single controller.

Separation Standard

A minimum distance or time, by which aircraft must be separated. Distances may be applied in the longitudinal, lateral and vertical axes.


See Standard Instrument Departure.

Speed Control

The process of adjusting an aircraft's speed for Air Traffic Control purposes.

Standard Arrival Route

A specified flight path from a Terminal Area Entry Gate to the duty runway. Inbound aircraft are often issued with a STAR by the controller responsible for the adjoining airspace prior to being handed off to the Approach Controller. Also called Standard Terminal Arrival Route and STAR.

Standard Instrument Departure

A clearance issued to a departing aircraft before it taxies, giving details of the route and altitudes it is to fly from lift-off from the designated runway to the point at which it leaves the Terminal Area or intersects its outbound route. SIDs can be either a Radar SID or a Procedural SID.


See Standard Arrival Route.

STAR Speed Restriction

A limitation on an aircraft’s speed within the Terminal Area imposed to assist orderly processing of busy traffic. The speed is included with other information in an aircraft’s STAR clearance.