Air Route Traffic Control Centers

TRACON
Photo Courtesy
Federal Aviation Administration (FAA)
Southern California TRACON
at San Diego, California

ARTCCs break down their assigned airspace into smaller, three-dimensional pieces known as sectors. For example, one sector may cover a geographic area of 500 square miles and range from the ground up to 23,000 feet, while a second sector covers the same geographic area but ranges from 23,000 feet in the air up to 37,000 feet. Each sector has an air traffic controller assigned to monitor it. The controller coordinates the flight paths of any aircraft that enter his or her sector and informs other controllers of aircraft that are about to enter theirs.

Occasionally, an aircraft never leaves the airspace of a single control center, as is often the case with commuter flights. Usually, h­owever, the aircraft's destination is in the jurisdiction of another ARTCC. In this case, the first ARTCC hands the aircraft off to the next ARTCC as it leaves the first ARTCC's airspace. The plane goes from one traffic control center to the next, until it reaches the boundaries of the destination ARTCC.

As an aircraft approaches its destination, the departure hand-off sequence is simply reversed. The regional ARTCC of the destination airport hands the aircraft off to the local TRACON, which guides the aircraft into the airport. As the aircraft prepares for final approach, the TRACON hands the aircraft off to the airport's ATCT. The ATCT guides the aircraft in for landing and tells it when it can go to the appropriate gate so the passengers can disembark.

In addition to the in-flight management provided by the facilities discussed above, the FAA operates flight service stations (FSS), centers where pilots submit flight plans and receive information about the weather and any other conditions that might affect their flight. Each FSS broadcasts weather, emergency and navigation information and advisories, and coordinates search-and-rescue efforts.

In the next section, we will talk about how the FAA provides safety regulations and licensing.

Changes Since Sept. 11, 2001
American intelligence agencies issued warnings of possible terrorist attacks in the summer and fall of 2001. While the FAA considered the possibility of a suicide hijacking, at the time officials considered sabotage or traditional hijacking more realistic threats [source: The 9/11 Commission]. After 9/11, the FAA began working on improvements in baggage screening and explosives detection. The administration also issued new guidance for air crew member training to identify potential human threats more effectively. Additionally, it published new standards for airlines and aircraft manufacturers to harden plane cockpit doors and limit cockpit access.