DALLAS -- On the afternoon of Sept. 25, Hurricane Helene was spinning in the Gulf of Mexico ahead of an expected landfall in Florida. But despite the impact the storm would inevitably have on flights, all was relatively quiet in the American Airlines Integrated Operations Center (IOC) here.
Mark Groat, the IOC's system customer service manager, looked over the ops center, where many of the approximately 375 on-duty staffers sat at desks crowded with computer monitors, some showing forecast tracks for the giant storm. "For there being a major hurricane moving into the Gulf, as you can see, there's not a lot of chaos," he observed.
American Airlines and its regional airline subsidiaries would eventually have to cancel 258 flights for the following day and another 492 on Sept. 27, FlightAware data shows, as Helene made its deadly journey from Florida's Big Bend through Georgia, South Carolina, North Carolina and Tennessee. (Those figures don't include American Eagle flights operated by contracted American partners, such as Republic Airways.)
But at this early stage, the airline had only canceled 44 flights for Sept. 26, the majority of them in Tampa, where the airport had already announced it would close.
Still, the ops center's calm before the storm belied the preparations American was undertaking in an effort to ease the magnitude of disruptions that a major storm like Helene -- or Milton, which arrived two weeks later -- would cause.
The morning of Sept. 25, IOC staff had been in touch with American general managers at Florida airports, gaining a clearer picture of operating constraints and to develop a storm plan.
The previous day, American had issued flight waivers in Florida for Helene, offering flexibility for ticketed travelers. But with forecast tracks showing that the monster storm would maintain hurricane-force winds well after landfall, the IOC had turned its attention to inland airports, including its hub in Charlotte, where decisions on flight waivers would also need to be made.
Meanwhile, Cancun, where American had 12 flights scheduled for that day, was already experiencing impacts from the storm. A late jog to the west by the hurricane had eased conditions there; so with the help of the ops center's in-house weather team, American was able to merely postpone its Cancun operations until a 1 p.m. start time rather than cancel flights.
Groat said that ahead of hurricanes as well as lesser adverse weather events, American's operations team always looks for remedies that can keep cancellations to a minimum. One way the airline does that is through its in-house Hub Efficiency Analytics Tool, known as HEAT, which shifts arrivals and departures after analyzing data about weather, gate availability, air traffic control constraints and more.
Ahead of Helene, American flight dispatchers also planned to be plugged in closely with FAA air traffic control centers. A key anticipated concern was weather over north Florida that was expected to impact routing on flights to and from the airline's hub in Miami.
Charlotte was another focus. American typically flies to its hubs in waves. A busy hour in Charlotte, Groat said, might see 70 arrivals, while a quiet one might have 30. But if air traffic control constraints are expected to limit arrivals there to 40 per hour, the carrier can strategically delay flights to level the hourly schedule and avoid or reduce cancellations.
Ultimately, American would delay 38% of its Charlotte arrivals between Sept. 25 and 28, according to FlightAware, and cancel 11.7%.
On that afternoon of Sept. 25, with Tampa Airport already having announced its next-day closure, American was also making other adjustments. The airline had begun selling additional flights out of the city that night, a move that served three purposes: It provided extra airlift to people needing to evacuate; it got aircraft out of the storm's way, where they could possibly be damaged; and it enabled American to generate revenue as it relocated planes out of what would be a closed station.
Looking at a screen displaying one of the numerous systems used by IOC staffers, Groat noted a last-minute flight the carrier had just begun selling from Tampa to Dallas.
"We've already picked up 45 passengers, and it has only been active an hour," he remarked.
During the most extreme weather events, of course, airlines can't always be strategic about which flights they cancel. But when they do have leeway, American attempts to cancel or delay flights in a manner that will have the least impact on travelers and on its operations.
Ultimately, a lead dispatcher decides which flights are canceled. But those decisions are made after taking input from various divisions within the airline, Groat explained. A maintenance router alerts the dispatcher about which aircraft need to be where for scheduled maintenance checks. A crew coordinator keeps on top of scheduling constraints that could result from crew reassignments. And a customer service advocate, like Groat, is responsible for determining which schedule changes will impact the least number of people and to the lowest degree.
For example, he said, if a flight to a hub contains a large group that is scheduled to transfer to a once-daily international flight, keeping that flight on schedule would be a priority.
"It's a very big jigsaw puzzle," Groat said.