ABSTRACT
There have been extraordinary changes in the machines that affect our daily lives. The equipment has become more complex, more sophisticated and more automated, while becoming more central to our activities. In commercial aviation, for example, two pilots were needed to fly the first commercially successful air transport aircraft, the Douglas DC-3, an aircraft that was designed over 80 years ago. The DC-3 could carry about 20 passengers at a speed of about 200 miles an hour over several hundred miles. Today, two pilots are also needed to operate a passenger-carrying aircraft, the Airbus A-380, but this aircraft transports over 500 passengers, several thousand miles, at speeds in excess of 500 miles an hour. Although the acquisition and operating costs of the A-380 are many times those of its predecessor, the per-seat operating costs are lower. This has helped to make air transportation affordable to many more people than in the DC-3 era.
