AIRPORT INTRODUCTION - PART 2

khoatd 29/7/2008, 11:59

Freight Services

Commercial airports also transport freight in addition to serving passengers. The majority of airfreight is flown in the belly cargo compartments of aircraft used for regularly scheduled passenger flights. Freight generally consists of products from many individual shippers and is commonly transported to and from the airport by truck. Upon arrival at the airport, movers load the freight onto pallets or into specialized freight containers bound for a common destination and then load the containers or pallets onto waiting aircraft.

A significant amount of airfreight consists of express-delivery package shipments that are carried by integrated carriers. Integrated carriers are companies such as Federal Express, United Parcel Service, and DHL, all of which specialize exclusively in the air transportation of small packages and the related ground collection and distribution. Such carriers fly high-value or time-sensitive parcels on airplanes that carry only such parcels.

Support Services

Most terminals at commercial airports contain restaurants, lounges, car rental agencies, banking services, newsstands, and other retail establishments. Larger terminals may also include observation stations, currency exchanges, a post office, and chapels. Some airports feature office areas, where traveling businesspeople can send and receive electronic mail and fax messages and also make telephone calls.

Commercial airports also provide plenty of short-term and long-term automobile parking. Airports can be reached by taxi and public transportation, but many travelers, particularly in the United States, get to and from an airport by driving an automobile. For these travelers, secure and convenient parking is a necessity. Airport parking is usually located in large parking ramps or nearby parking lots. Monorails, shuttle buses, or long, moving sidewalks are used to ferry passengers from the parking lots to the terminal buildings.

Airports also maintain fire departments that are specially trained and equipped to fight aircraft fires. The local fire department usually provides fire protection for the rest of the airport. Airport fire trucks are equipped with water and a substance called aqueous film forming foam (AFFF). AFFF is used to combat aircraft fuel fires. The foam covers burning fuel more effectively than water alone and acts like a blanket to extinguish the fire. Airports must also be equipped for the removal of ice and snow from aircraft, runways, taxiways, and other access roads.

Airport Security

Ensuring the safety of passengers and aircraft is a major concern at airports. Security personnel operate metal detectors and X-ray machines that screen baggage for possible weapons or illegal substances. Security personnel also require that each passenger show photo identification before entering an aircraft. Many areas of an airport, especially those areas that contain critical equipment, are protected by security personnel and are off-limits to the public.

In the wake of the September 11, 2001, terrorist attacks in the United States, airport security became the responsibility of the federal government. The United States Congress enacted the Aviation and Transportation Security Act in response to the attacks, which had exposed a number of weaknesses in airport and airline security. The new law expanded the number of baggage screeners, imposed standards for their training, and made them federal employees for an interim period of time. Beginning in January 2002, it required that all passenger luggage, including checked luggage, be screened. By the end of 2002, all checked luggage was to be put through special explosives-detecting devices. The law increased the number of armed federal air marshals flying on domestic flights and required international airlines to turn over advance copies of their passenger lists to U.S. Customs officials for background checks to screen out suspected terrorists.

Airport Construction and Administration

Selecting a new airport site is a complex, time-consuming, and expensive proposition. Local governments usually make the decision to construct or expand public airports. The money to fund construction for these airports comes from taxes or from the sale of bonds. Airport sites are selected based on airport traffic volume, the nearby population, availability of ground access, and existing air traffic flows. Once a proposed site has been selected, a detailed site plan is prepared. Aircraft noise plans, environmental impact studies, and building designs must be approved by the FAA before funding can be obtained. Only when these tasks have been completed can actual construction of an airport begin.

Airports are owned and operated by many different agencies. Most small airports are privately owned. Large commercial airports are usually owned by city governments, regional port or airport authorities, or state or federal agencies. Most airports are operated by the agencies that own them, but some are operated by private organizations that have a contract to operate them or that lease them from their owners. Some private companies have purchased entire airports from their owners and operate them for profit.

Airports receive revenue from a number of sources. Airports charge landing fees to the airlines for each airplane that lands and takes off from the airport. Airlines, food service companies, and retail establishments rent portions of the terminal. An airport also makes money from fees charged at parking lots. Airports can also charge a fee on each ticket sold to pay for improvements. Expenses involved in operating an airport include terminal and runway maintenance; utilities such as water, electricity, and heat; airport administration and salaries; and fire and security services.

History

Airports have grown from simple grass-covered fields into some of the busiest transportation centers in the world, moving millions of passengers worldwide. As airline traffic increases, new airports are built to accommodate more passengers.

Airport Development

Early airplanes were light and had low operating speeds, so they could operate from any relatively level cleared field. Takeoff and landing fields in the 1910s and 1920s were generally built in any location that was convenient to the population being served. These airfields had no designated runways, because the airplanes did not require specially prepared or paved surfaces. Pilots simply positioned their aircraft into the wind and, after a short ground run of 300 to 900 m (1,000 to 3,000 ft), took off into the air.

Because airfields were relatively easy to create in the early days of aviation, many cities had more than one. Terminal buildings, if they existed at all, were often multipurpose buildings housing the offices of a few airlines, weather observers, and air traffic controllers, as well as ticket counters, snack bars, and passenger-waiting and baggage-pickup areas.

Multiengine airplanes, introduced in the 1930s, were heavier and needed longer paved runways to take off and land. As a new round of airport construction began, airport builders favored sites away from central downtown districts, such as outlying farm areas or unpopulated marshlands. These marginal sites were inexpensive, provided enough space for expansion, and were also clear of obstructions such as tall buildings. In most cities, government officials chose to designate only one airport in their region as a major airport. The other fields were closed, and their sites were subsequently used for shopping centers, industrial parks, and residential developments.

These second-generation commercial airports of the 1930s were designed to serve airplanes that usually carried up to 75 passengers. Because airplane capacity was still relatively small, all terminal functions were handled on a single floor. Terminal buildings were usually of the gate terminal design, with airplanes on one side of the building and automobile parking on the other.

With the introduction of jet airplanes into commercial service in 1959, facilities at many existing airports became outdated or obsolete. To correct this, another round of construction and expansion began. To allow long-range operations by the heavier and faster jet aircraft, runways now needed to be extended in length to about 3,000 m (about 10,000 ft). Terminals designed for the passenger volumes of earlier, smaller aircraft were no longer adequate for the new jet airplanes, which could seat more than 150 passengers on each flight.

New concepts in terminal design that were implemented in the 1960s featured much larger architecture than that of earlier terminals. Many new terminals were built by specific airlines to serve their own customers.

In the years following the deregulation of the U.S. domestic air-transport industry in 1978, airlines began converting their operations to hub-and-spoke systems. In this system, an airline’s passengers are collected by flights from many spoke cities and are flown to a hub airport, which is normally located at a centralized point in the airline’s route system. Passengers arrive at the hub in a wave of flights arriving at approximately the same time. During the time the airplanes are on the ground at the hub (about 1.5 hours), passengers transfer to other airplanes that are going to their ultimate destination. Then all flights in the wave depart to the spoke cities and the whole process begins again. This pattern is repeated throughout the day to provide service at convenient frequencies.

Prior to the establishment of hubs in the United States, long, nonstop domestic flights of 4,000 to 5,000 km (2,500 to 3,000 mi) were traditionally flown in large wide-body jets holding from 250 to 400 seats. These large jets flew usually once or twice per day for each airline in the market. With the advent of the hub-and-spoke system, nonstop flights have been largely replaced by shorter flights and smaller jets that fly as many as 12 connecting flights per day.

Modern Airports

Denver International Airport is the newest major commercial airport in the United States. Located outside Denver, Colorado, it opened in 1995. The airport covers an area of 137 sq km (53 sq mi). It has five runways, each 3,700 m (12,000 ft) long. The runways are at least 1,300 m (4,300 ft) apart, permitting two or three streams of aircraft to land simultaneously. The control tower is 33 stories tall. The terminal and concourses are in the center of the airfield, cover 140,000 sq m (1,500,000 sq ft), and include 94 airline gates.

The Kansai International Airport in Ōsaka, Japan, was built on an artificial island located in Ōsaka Bay. The island is connected to the mainland by a bridge and is served by several ferries. The airport opened for business in 1994. Its location away from populated areas eliminated noise-pollution problems, allowing Kansai to become the first Japanese airport that is open 24 hours a day. The airport serves over 25 million passengers per year. The single runway is 3,500 m (11,000 ft) long, and a second parallel runway is planned for the future.

The Hong Kong Chek Lap Kok International Airport opened in 1998. It has a single runway 3,800 m (12,400 ft) long, as well as facilities able to meet the demands of 35 million passengers and 3 million tons of air cargo shipped annually. A second runway is under construction. The airport was built on an island that was excavated 27 m (90 ft) down to reach solid bedrock and then refilled with topsoil. The terminal, which is over 1 km (0.6 mi) long, includes 75 gates. The total cost of the airport was $20 billion.