1. Introduction
During the one hundred years since the first flight of Orville and Wilbur Wright, the air transport industry has grown into a major sector of the global economy. Even more importantly, it has become essential to developing and maintaining cultural and economic links among countries and peoples. The airlines alone generated more than $300 billion in revenues in 2002, a lean year, and carried about 1.6 billion passengers, a number expected to grow at an annual rate of 4%–5% over the next 20 years according to most forecasts. According to the industry “air transport provides 28 million direct, indirect, and induced jobs worldwide” and carries “over 40% of the world trade of goods, by value” (Collaborative Forum 2003).