On John DiScala's recent flight from Fort Lauderdale to Los Angeles, he noticed something unusual going on at the American Airlines gate next to him.
The passengers, headed to Chicago, were asked to board the aircraft based on whether they had carry-on luggage or not.
"First they boarded the elites and then they offered people who did not have carry-ons except for personal items to board next," DiScala said.
Personal items, in airline speak, typically include laptop bags, handbags and anything else that can fit under the seat in front of you.
DiScala, world traveler, elite frequent flier and the man behind the popular travel web site JohnnyJet.com knows something unusual when he sees it. So he tweeted the airline: "I wonder if @AmericanAir is testing out a new boarding procedure. They just invited those without carry-on's to board 2nd."
The American Airlines twitter handle responded, "We know that the WAS airports were trying a new boarding system, John, but we hadn't heard that FLL was too."
WAS is not an airport code, but likely refers to the three Washington, D.C.-area airports. FLL is the Fort Lauderdale-Hollywood International Airport in Florida.
When asked for comment by ABC News, American Airlines said, "We test many different concepts in an effort to continually improve the customer experience. With this in mind, we're conducting a test for a boarding process whereby customers who do not have any baggage to stow in the overhead compartment will be boarded in a separate group. This is a limited test and results are still being analyzed.
Given that it's a limited test, the airports and flights chosen may change at any time."
The airline would not respond to repeated requests to confirm testing airports.
Asking people without carry-ons to board first, said DiScala, makes sense for the airline in two ways.
First, the boarding process would theoretically be faster and smoother if people aren't waiting in the aisles for those with carry-ons to load their belongings into the overhead bins.
Second, passengers who like to board earlier rather than later may be incentivized to check their bags, a source of revenue for the airline.