Head in the Sky, Feet at the Gate
A scientist formulates an algorithm to determine the best boarding method.
March 18, 2008 -- When it comes to boarding an airplane, Jason Steffen thinks we do it all wrong.
But Steffen is not your typical, impatient traveler. He's an astrophysicist whose brain is cranking a mile a minute to determine — scientifically — how to hurry things along.
"If you board in groups from the back to the front, that's the slowest standard method," said Steffen, a Brinson postdoctoral fellow at the Fermi National Accelerator Laboratory in Batavia, Ill. "You're trying to get as many people as possible crammed into a small place and only one or two people can get their stuff in place."
Though he usually studies lofty things like extra-solar planets and black matter, Steffen is now examining airplanes before they ever get off the ground.
It all started on a particularly crazed morning in Seattle, complete with long security and boarding lines. It's since turned into an effort that uses a convoluted calculation called the Markov Chain Monte Carlo optimization algorithm to determine the optimal way to keep the aisle clog-free.
"That last line was moving so slowly, I thought, 'You know, there's got to be a quicker way to get people onto an airplane,'" Steffen recalled.
Ideally, passengers would board in a pattern that staggers them every other row throughout the plane, so there's sufficient room in the aisles for several people to load their luggage in the overhead bins at once, Steffen found.
No doubt Steffen's finding bucks current convention. Major carriers like American and Delta said they generally board from back to front, with exceptions made, for example, for passengers traveling in first class or with special needs.
"We've tested other ways, we've found this works best for us," says American spokesman Tim Wagner. "That's where the clog happens — with people not being able to get past someone standing in the aisle."
But carriers that take less conventional approaches, like Southwest and Jet Blue, come closer to the right idea, Steffen's research suggested.
"What I found is that if you just make an announcement that, 'OK, the plane's open, get on,' it boards just as fast, if not faster," Steffen said.
Jet Blue takes a hybrid approach, based on testing conducted a couple of years ago, that has prompted the carrier to board its last five rows first, then turn to random boarding for the rows up front.
A rare carrier that does not assign seats, Southwest recently revised its boarding procedures after hearing customers were dissatisfied with having to arrive early at the gate to wait in line. After talking with customers, sending out surveys, and testing new boarding processes at two airports, today, Southwest gives people a letter and number indicating their reserved space in line. Upon boarding, they still choose any open seat on the plane.
Southwest director of product development, Chad Wadley, said that typically results in people boarding the plane from front to back, staggering among aisle and window seats before filling in middle seats.
"When you have people boarding and finding their place to sit, we've found it takes a lot longer to turn the plane around," Wadley said.
Steffen has since submitted his findings to the Journal of Air Transport Management and is awaiting publication. Meantime, friends and colleagues are giving him plenty of fodder for his next project — whether devising the best way to program an elevator or discovering the ultimate way to program traffic lights on a grid of city streets.
"People have made suggestions, none of which I've actually seriously considered," Steffen said.