What does an air traffic controller do?
Controllers keep aircraft safely separated while moving them efficiently through airspace. The job breaks down into a few core tasks.
Separation
The primary job. Keep aircraft at least 5nm apart laterally (3nm in terminal areas) or 1,000ft apart vertically. Every decision a controller makes serves this goal.
Clearances
Controllers issue instructions to pilots: altitude assignments, heading vectors, speed restrictions, approach clearances. Each clearance must be read back by the pilot to confirm understanding.
Sequencing
Arrivals need to be arranged in order for landing. Controllers space aircraft using speed control and vectors, merging traffic from different directions into a single line for the runway.
Handoffs
Airspace is divided into sectors. When aircraft cross sector boundaries, the current controller hands responsibility to the next. This involves coordination between both controllers and a frequency change for the pilot.
Types of controllers
- Center (en-route) - manages high-altitude traffic between sectors, typically above 18,000ft
- Approach/departure (TRACON) - manages traffic arriving at and departing from airports, typically below 18,000ft
- Tower - manages aircraft on and near the airport surface - takeoffs, landings, and runway crossings
- Ground - manages taxiing aircraft between gates and runways
Practice it yourself
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