Tess Vigeland: If you’ve flown American Airlines recently, you may have noticed something different at the gate. The airline has again revamped how it gets folks on the plane. What’s out? Back to front. What’s in? “Complete chaos in the cabin,” at least according to the flight attendants union.

It’s yet another salvo in the long battle to get people in their seats as quickly as possible and thus save time and money. Marketplace’s Adriene Hill reports.

Adriene Hill: There are some questions in life that just don’t have easy answers. Boarding an airplane is one of them.

David Sweirenga: There’s a lot of ways to skin that cat.

David Swierenga is an airline industry analyst.

Sweirenga: The operations research departments at the airlines have gone nuts trying to figure out what’s going to be the most efficient way and the way passengers actually prefer.

A lot of really smart people have tried to figure this one out — mathematicians, logistics experts. But, says Steven Lott at the Air Transport Association, this one’s going to take more than big brains.

Steven Lott: Boarding a plane is part science and part art.

You’ve got different planes, different rewards programs. Screaming babies and stressed businessmen. All those factors add up to a whole lot of experiments: There’s the reverse pyramid, which is boarding back-to-front. Open boarding — think Southwest. Skin in — boarding window seats first. And American’s new plan to board different parts of the plane at the same time.

Why keep futzing?

Gary Hogg: The delays that occur in boarding cost the airlines a lot of money.

Dr. Gary Hogg is a retired engineering professor from Arizona State University. He and his colleagues helped America West with its boarding process.

Hogg: What an airline strives to do is maximize the amount of revenue-generating hours that it flies.

According to one study, waiting on the ground can cost airlines $30 a minute. It’s also really annoying for those of us anxious to get where we’re going.

I’m Adriene Hill for Marketplace.