Technology in the Airline Industry
Computers have become crucial to the airline industry. They are used to book tickets, plan flights, schedule aircraft and crew, oversee maintenance, and set fares.
From ticket reservations to aircraft design and manufacture, computers have helped airline operations become more efficient and flexible. The rise of personal computers and the Internet has given passengers complete control over booking their own flights and seat selections. The complex and fluid airfare system that computers have made possible enables savvy travelers to find low fares on many routes.
Using the Internet, passengers can search for find the best fare or flight, choose seats, make reservations, pay for the ticket, and print receipts and boarding passes.
Computer-aided design and computer-aided manufacture (CAD/CAM) have greatly reduced the cost of producing aircraft. Computers produce accurate drawings and can alert designers to possible conflicts before a design is produced. They can also manufacture parts more precisely and faster than humans. Parts for the 747-400 (shown here) are made by CAD/CAM. The Boeing 777 was the first airliner completely designed on computer.
Computer reservation systems have led to code sharing-agreements between airlines that allow travelers to fly on more than one carrier on a single ticket. Code sharing increases and optimizes the flow of passenger through an airline’s network. A major carrier may have code sharing agreements with regional, commuter, and foreign airlines.
In the late 1950s, American Airlines pioneered the use of a computer reservation system, and in 1963 American installed its Semi-Automated Business Environment, or SABRE. Other airlines followed American’s lead and developed their own computer reservation systems.
Information above from: http://www.nasm.si.edu/americabyair/jetage/jetage16.cfm
Nowhere is the impact of computer technology on commercial aviation more apparent than in the cockpit of a modern jetliner. In Airbus Industrie’s A320, the traditional control column, customarily positioned in front of the pilot and used to bank the plane and make it climb or descend, has been replaced by a simple but sophisticated control stick (joy stick) at the side of the cockpit. Dozens of dials and gauges have been supplanted by a handful of computer screens.
Different computer systems are responsible for each of these alterations in the pilot’s office. In overall command are twin flight-management computers, one of which serves as backup to the other. Before takeoff, the two-man crew uses either keyboard to enter the flight plan - altitudes, speeds, and intermediate destinations - simultaneously into both computers; the information is displayed on a small screen above each keyboard. After the plane is aloft, the computers take over, guiding the craft, constantly checking on its many complex systems, and feeding data to subsidiary computers.
1 The Instrument Panel
Among the most important of these are the display-management computers, which control the instrument panel. Though a few standard instruments remain as backups, six computer screens supply all essential flight and performance information in easy-to-read formats. The Primary Flight Displays, one each for pilot and copilot, do the work of several key instruments, showing the planes altitude, heading, airspeed, and altitude. The Navigation Displays present directional and routing information on a compass layout, and can also project a radar image of the weather. Two System Displays provide continual updates on the functioning of the engines and other critical components; should a problem arise that the flight-management computers cannot handle, diagrams and checklists appear on these screens to guide the pilots through corrective procedures.
The two side sticks are managed by another computer, part of the A320s fly-by-wire system. Stick movements are translated into electrical signals, thus eliminating the bulky mechanical connections of older designs. The approach prevents the pilot from ever overstressing the plane by maneuvering the stick too violently: Before the signals are relayed to control surfaces on the wings and tail, they pass through the fly-by-wire computer, which acts like a damper, moderating the most extreme gestures.
Computers have proved to be such excellent assistants on the flight deck that they have for several years permitted some commercial airliners to be flown by a crew of two instead of three, as required in the 1970s. Besides saving the third officer’s salary, computer conserve fuel by flying a plane straighter than a human pilot can, improve the reliability of aircraft, and simplify the troubleshooting of malfunctioning equipment. Taken altogether, the economic benefits of computer-controlled flight-management systems have far exceeded the cost of installing them.
2 Fly-By-Wire
A few airplane builders have taken yet another step toward the fully computerized airliner by installing fly-by-wire control. In this system, digital signals instead of mechanical or hydraulic linkages transmit movements of the pilot’s hand and feet to the aircraft’s various control surfaces - ailerons on the wings for banking the plane, elevators at the tail to raise or lower the nose, and a rudder to help the aircraft turn. Developed by aeronautical engineers in the mid-1970s for high-performance combat aircraft like the F-16 bomber, the system has been built into the Airbus A320, an airliner produced by a consortium of European aircraft manufacturers.
3 Airliners that can Fly Themselves
The autopilot and auto-throttle systems have joined the ranks of microprocessor-based systems for commercial aircraft. A system called the Flight Management Computer System (FMCS) has been installed in the 737 test-bed aircraft. The computer of the FMCS keeps track of every aspect of an airplane’s performance, from airspeed and rate of descent to throttle setting and fuel consumption.
At the core of the system is a database that contains a complete performance profile of the aircraft. In this database resides detailed information on such topics as the maximum and minimum speeds at which the plane will fly, the amount of power required to maintain altitude, climb, or descend at a various speed, the effect of payload on performance, as well as facts about the aircraft’s fuel consumption at different speeds and altitudes. The database even contains the manual of emergency procedures for the aircraft. Should one of the engines fail, for example, the FMCS first alerts the pilot to the malfunction by signaling the caution advisory system to change the color of the appropriate engine instrument and to issue the proper visual warnings or cautions, some of which are accompanied by an aural signal. Automatically, the EICA displays all the steps for dealing with the problem, from new power settings for the remaining engines to the procedure for restarting the dead one. In the case of multiple failures - the engine and the landing gear, for instance - the EICAS assigns priorities to each, so that the pilot can deal with the most critical emergency first.
An airline’s route structure - airports, navigation aids between them, radio frequencies, and the like - can also be recorded in the FMCS database. This enables the crew to program the computer with most of the information needed to get an airliner to its destination - including special requirements such as the route to fly immediately after takeoff in order to conform to noise-abatement procedures in effect at particular airports, and details about the primary cross-country route and alternates. The computer can even be directed to automatically switch radio frequencies as necessary to enable the pilot to keep in contact with air-traffic controllers on the ground. If the plane’s pilot wished to do so, he could program an entire flight, beginning with the takeoff roll, and would not have to touch the controls at all until after the aircraft had landed.
4 The Instrument Panel Revisited
At first, electronic engineers demonstrated digital instrument that looked unlike anything the aviators had used before. The all-important airspeed indicator was replaced with a kind of bar graph in which the length of the bar showed the craft’s speed. But pilots preferred the familiar to the unusual; they simply did not want a lengthening and shortening bar of light to replace the movement of a pointer around a dial.
Avionic firms believed they had the answer when, in the late 1960s, they developed a video display that reproduced conventional dials on a small television-like screen. Boeing installed these as well as digital autopilot and navigation computer in a 737 jet and showed it to pilots.
The response was less than ecstatic. The reason, this time, was the issue of color rather than shape. Conventional instruments were boldly colored to show at a glance safe zones and danger zones of operation, such as high engine speed or low oil pressure. The actual numbers on an instrument were often no more significant than whether the instrument’s pointer had settled solidly in the green range or was creeping toward the red. The digital instruments that Boeing so hopefully demonstrated in the 737 displayed their information in black and white, and not even clever use of contrasting grays could compensate for the vivid colors that they were intended to represent.
The breakthrough came when a small color CRT was developed that could withstand the rigors of flight. It addressed the human-factors considerations that became the primary focus of NASA and FAA groups. If the pilots are not comfortable with technology designed for the cockpit - it will not be used.
5 Recording a Flight’s Vital Statistics
Since the 1960s, regulations have required commercial aircraft to carry two crash proof recorders, popularly know as black boxes. One is a simple audio recorder that captures the crew’s voices. The other is a more complex data-collection device designed to chronicle various features of the plane’s performance.
Computer technology and the advent of microprocessors revolutionized the gathering of flight data. Today’s flight-data acquisition unit collects, organizes and digitizes analog signals from a host of sensors, permitting the flight recorder to register on magnetic tape dozens of flight parameters, from the plane’s attitude, its pitch up and down or roll from side to side to the status of its many mechanical and electrical systems. If trouble strikes, this wealth of digital data can be used in computer models to provide a detailed reconstruction of the events that lead to calamity.
6 A Graphic Reconstruction
To unravel the mystery of a flight crash, analysts turn to the plane’s flight data recorder. And to help make sense of its stream of numbers, they employ a computer that is programmed to translate selected flight data into a graphic animation of the event. The resulting images make it easier to study, among other things, the responses of the pilot to the developing crisis.