Airlines avoid up to 80 percent of crew-related delays through advance planning, according to the authors of a Dartmouth study on the commercial airline industry. The research explains the complex reality of crew scheduling and provides an inside look at the techniques used by airlines to absorb system delays.

While individual airlines use proprietary systems for crew planning, this is the first study that publicly describes how crew itineraries are developed. It is also the first open study of how airlines weigh planned costs and disruption costs when deciding crew schedules.

Understanding the rules and regulations that define how airlines work and that often compound frustrating delays for passengers is difficult. The analysis explains how positioning of flight crews attempts to ease travel disruptions while saving airlines and consumers billions of dollars.

“Airlines are among the world’s most complex businesses,” said Vikrant Vaze, an assistant professor of engineering at Dartmouth’s Thayer School of Engineering. “Understanding the sophisticated planning systems used by airlines to schedule crews—as well as understanding how delays impact the air travel system—are both massive tasks, but such information can result in great savings for the airlines and the flying public.”