How to Load an Airplane Faster
by Virginia Postrel • May 10, 2006 at 12:12 am
Dave Demerjian of Wired News reports on how airlines are using math to expedite boarding. The article is well worth a full read, but here's an excerpt:
America West Airlines, which became US Airways after a recent merger, has led the way in rethinking passenger boarding, working with engineers at Arizona State University to develop a system that speeds the process by reducing interference between passengers.
According to Tim Lindemann, US Airways' managing director of airport services, streamlining the boarding process was one part of a larger effort to reduce turnaround times at what was then America West. "We were looking at every possible way to shave time off the process," he says.
Convinced that there was a statistical solution to the problem, Lindemann approached Arizona State University's industrial engineering department. "We have a great university in our backyard, and hoped they could help," he says. "The engineers there immediately understood the problem we were trying to solve, because they had witnessed it themselves. They had been on our flights."
Professor René Villalobos and graduate student Menkes van den Briel began reviewing boarding systems used by other airlines. "The conventional wisdom was that boarding from back to front was most effective," says van den Briel. The engineers looked at an inside-out strategy that boards planes from window to aisle, and also examined a 2002 simulation study that claimed calling passengers individually by seat number was the fastest way to load an aircraft.
The two then developed a mathematical formula that measured the number of times passengers were likely to get in each other's way during boarding. "We knew that boarding time was negatively impacted by passengers interfering with one another," explains van den Briel. "So we built a model to calculate these incidents."
Villalobos and van den Briel looked at interference resulting from passengers obstructing the aisle, as well as that caused by seated passengers blocking a window or middle seat. They applied the equation to eight different boarding scenarios, looking at both front-to-back and outside-in systems. "Ultimately, the issue America West needed to address was time," explains van den Briel. "We figured a system that reduced interference between passengers would also cut boarding time."
I'm sure the operations research is good, but airlines have some tough behavioral issues to deal with too. Passengers all want to board first. Some flout the rules, knowing that most airlines ignore line cutting. (A confrontation slows the boarding process.) And, at least on some flights, most passengers are actually entitled to early boarding, thanks to their--our--illustrious frequent flyer status.