Air Traffic Control & Management To fully understand the varying performance characteristics of aircraft, it is necessary to understand certain elements of the environment in which they operate. The performance of all aircraft is affected significantly by the atmospheric conditions in which they operate. These conditions are constantly varying, based simply on the daily heating and cooling of the earth by the sun, and the associated winds and precipitation that occur.
A Brief History International Civil Aviation Organization (ICAO) in 1944 helped to standardize recommended air traffic control procedures internationally. Today, air traffic control in each country is operated either by its federal government or by private corporations under governmental supervision and regulations. Examples of international air traffic control organizations include: Federal Aviation Administration (FAA) in the United States, National Air Traffic Services Ltd. (NATS) serving the United Kingdom
A Brief History Air traffic management is made up of and responsible for a series of hierarchical control facilities, ground and satellite based navigational aides and aircraft routing procedures, as well as a defined system of air routes and airspace classifications.
Air route traffic control centers (ARTCCs) Geographical area is divided into sectors Each sector is normally provided with one or more air route surveillance radar (ARSR) units which cover the entire sector and allow for monitoring of separation between aircraft in the sector The terminal approach control facility (TRACON) monitors the air traffic in the airspace surrounding airports with moderate to high density traffic. It has jurisdiction in the control and separation of air traffic from the boundary area of the air traffic control tower at an airport to a distance of up to 50 mi from the airport and to an altitude ranging up to 17,000 ft. This is commonly referred to as the terminal area.
The airport traffic control tower (ATCT) Air route surveillance radar
Navigational Aids Aids to navigation, known as NAVAIDS, can be broadly classified into two groups, ground-based systems and satellite-based systems. Each system is complimented by systems installed in the cockpit.
Navigational Aids Ground-Based Systems The oldest active ground-based navigational aid is the nondirectional beacon (NDB). The NDB emits radio frequency signals on frequencies between 400 and 1020 Hz modulation. NDBs are typically mounted on a pole approximately 35 ft tall. Aircraft navigate using the NDB by referencing an automatic direction finder (ADF) located on the aircraft s panel. The ADF simply points toward the location of the NDB. Figure 3-9 illustrates an ADF system.
Navigational Aids Ground-Based Systems Very high frequency omnirange (VOR) These stations are located on the ground and send out radio signals in all directions. Distance Measuring Equipment Distance measuring equipment (DME) has traditionally been installed at VOR stations in the United States. The DME shows the pilot the slant distance between the aircraft and a particular VOR station.
Navigational Aids Ground-Based Systems Air Route Surveillance Radar A long-range radar for tracking en route aircraft has been established throughout the continental United States and in other parts of the world. Instrument Landing System Until the recent proliferation of published navigation procedures which rely on the satellite based GPS system, the instrument landing system (ILS) was the only groundbased system certified to provide both lateral and vertical guidance to aircraft on approach to an airport.
Navigational Aids Ground-Based Systems Airport Surface Detection Equipment In use in many of the busier airports within the United States and elsewhere. Satellite-Based Systems: Global Positioning System (GPS) Perhaps the greatest impact on air traffic management since the beginning of the twenty-first century has been the development, acceptance, and proliferation of navigational procedures which rely on the global positioning system