Why airplanes board front to back — astrophysicist reveals the better, more efficient alternative

It might seem a bit backward.

Boarding aircraft front to back seems ludicrous given how often the aisle is obstructed by passengers attempting to stow their luggage, among other issues. However, there’s a reason behind this seemingly counterintuitive policy.

Most airlines use a system called block boarding, where people are let on in order of their zone, Travel and Leisure reported. As the first zones generally constitute first class, economy plus and frequent flyers, this results in the plane being boarded from front to back.

While this might seem like a recipe for passenger traffic jams, the logic is that it incentivizes people to “book premium cabins, achieve frequent flyer status or sign up for an airline credit card to be in a better boarding zone — and therefore have space in the overhead bins for their carry-ons,” per the magazine.

As they point out, those who board last are less likely to find a spot for their bag. One notable exception to this fly-rarchical system is budget carrier Southwest Airlines, which has a “first come first serve” policy by the subway.

Fortunately, there exists a seating system that mathematically allows passengers to board faster than all the other ones.

Devised in 2008 by Nevada astrophysicist Dr. Jason Steffen, the Steffen Method seats passengers in alternating rows with window seaters boarding first, then middle seats, then the aisles.

“This would mean boarding all of the passengers on even rows, seat A first, then going to the odd rows, then the other seats,” Dr. Steffen told Travel and Leisure.

Having passengers disperse throughout the cabin’s interior mitigates the risk of bottlenecks caused by passengers stopping in the aisle to put away their luggage.

Dr. Steffen based this flyer organization technique on a formula called Markov chain Monte Carlo that helps determine the best route.

He would passengers using this computer model, then switch two flyers to see if the new configuration boarded faster, said Steffen.

“If yes, keep the new order. If no, flip a coin and keep the new order depending on the result,” Steffen explained. “Over time, the passengers will tend to organize themselves in the fastest order.”

The caveats are that this process is often hampered by human error and that it would theoretically split up families by prioritizing efficiency over humanity.

Dividing families is also the reason many flight experts poo-poo the seemingly intuitive back-to-front boarding process, which experts say causes as much congestion as the converse policy.

Former American Airlines CEO Doug Parker listed these while explaining why he would never adopt this policy in a 2021 meeting with flight attendants (when he was still in charge).

“We have looked at that, we’ve studied it, and while it may seem better to have people go from back to front ..what you really want to do is window-to-aisle but if you do that you split up families and things,” he declared. “When you do back-to-front there is just as much if not even more in some cases interaction with customers getting up and out of the aisle as there is with our process.”