3. What sequencing rules do you think the tower controllers use? Air traffic controllers have one of the most stressful jobs in the world. They are responsible for the lives of thousands of passengers who fly every day in and out of the world’s airports. Over the last 15 years, the number of planes in the sky has doubled, leading to congestion at many airports and putting air traffic controllers under increasing pressure. The controllers battle to maintain separation standards that set the distance between planes as they land and take-off.

Sheer volume pushes the air traffic controllers’ skills to the limit. Jim Courtney, an air traffic controller at La Guardia Airport in New York, says ‘There are half a dozen moments of sheer terror in each year when you wish you did something else for a living’.

New York – the world’s busiest airspace The busiest airspace in the world is above New York. Around 7500 planes arrive and depart each day at New York’s three airports, John F. Kennedy, La Guardia and Newark. The three airports form a triangle around New York and are just 15 miles from each other. This requires careful coordination of traffic patterns, approach and take-off routes and using predetermined invisible corridors in the sky to keep the planes away from each other. If the wind changes, all three airports work together to change the flight paths.

Sophisticated technology fitted to most of the bigger planes creates a safety zone around the aircraft, so that when two aircraft get near each other, their computers negotiate which one is going to take action to avoid the other and then alerts the pilot who changes course. Smaller aircraft, without radar, rely upon vision and the notion of ‘little plane, big sky’.

During its passage into or out of an airport, control of each plane will pass through the hands of about eight different controllers. The airspace is divided into sectors controlled by different teams of air traffic controllers. Tower controllers at each airport, together with ground controllers who manage the movement of the planes on the ground around the airport, control the planes landing and taking off. The Terminal Radar Approach Control (TRACON)

controllers oversee the surrounding airspace. Each New York air traffic controller handles about 100 landings and take-offs an hour, about one every 45 seconds.

TRACON controllers The 60 TRACON controllers manage different sectors of airspace, with planes being handed over from one controller to the next. Each controller handles about 15 planes at a time, yet they never see them. All they see is a blip on a two-dimensional radar screen, which shows their aircraft type, altitude, speed and destination. The aircraft, however, are in three-dimensional airspace, flying at different altitudes and in various directions. The job of the approach controllers is to funnel planes from different directions into an orderly queue before handing each one over to the tower controllers for landing.