United Airlines just made their boarding process faster. But an astrophysicist says there's still a quicker way.

• United Airlines introduced a new system for boarding passengers on October 26.
• It claims the new procedure will save two minutes of flight time.
• But Jason Steffen, an astrophysicist at the University of Nevada, says boarding could be even faster.

An astrophysicist said United Airlines' new airplane boarding system could be even faster.

United announced that from October 26 it was introducing a system known as WILMA, where economy passengers in window seats would board first, followed by middle seats, and then aisle seats, per a memo shared with Insider.

The airline said that the new method is two minutes faster than the old system and is more popular with customers.

"We're excited to bring WILMA back to provide a smoother window, middle, aisle boarding process flow that helps get passengers in their even seats faster," a spokesperson told Insider.

But Jason Steffen, an assistant professor of physics at the University of Nevada, Las Vegas, said United's method could still be improved.

Steffen developed his own methodology more than 15 years ago after tiring of the queues he faced every time he boarded a plane, he told The Wall Street Journal.

"There should be a solution to this — no matter how weird it might be," Steffen said.

That's why he created "the Steffen method."

In this system, the first passenger to board a single aisle plane would be the person sitting in the window seat of the back row. If that were seat 30A, for example, the next person to take their seat would be the window seat two rows in front — 28A.

This would carry on until the even window seats on one side of the aircraft were filled, per The Journal. The even window seats on the opposite side of the plane would come next, followed by window seats on odd rows. That pattern is then replicated for the middle and aisle seats.

This helps reduce the probability of bottlenecks by maximizing the number of passengers loading their luggage into overhead storage, per The Journal.

In a 2011 paper that tested five boarding methods on a mock-up plane, Steffen's method was found to be the fastest.

But Steffen's way does have its limitations, as it does not take into account families or groups who may be sitting together.

United ran its own tests on a range of boarding strategies, including Steffen's method, and found that WILMA was actually the fastest, a spokesperson for United told The Journal — although it didn't use Steffen's exact model, as it continued to board groups and fliers with premium memberships first.

Steffen also acknowledged that he lacked knowledge of how the boarding process was affected by "the rest of the system."

"I think it's a lot more complicated than people realize to run a multibillion-dollar airline," the astrophysicist told The Journal. "It's easy for me to armchair-quarterback what they should be doing when there's probably a lot more stuff going on that I don't know about."

With airline companies trying to economize on every second of flight time, the order that passengers board a plane can lead to millions in savings a year.

Southwest Airlines has made Hartsfield-Jackson Atlanta International Airport into an "innovation zone" where it is trialling eleven new concepts — including upbeat music and flashing lights — to try and slash boarding times.