American Airlines CEO Robert Isom told CNBC is working to make up a margin gap it has with rivals United and Delta.

The carrier is working on improving reliability, investing in more upscale cabins and lounges, and preparing a wide-body plane order from Boeing or Airbus to attract higher-spending travelers as early as this year.

The airline is forecast to increase earnings this year, on an adjusted basis, by close to 80% from 2025, according to analyst estimates.

Isom and American's roughly 139,000 employees have to make the changes clear to customers.

FORT WORTH, Texas — American Airlines CEO Robert Isom has a math problem.

The carrier is flying about 6,500 flights per day this year — nearly an entire Alaska Airlines more worth of travel more than its closest competitor, according to Cirium — yet American's profit gap has grown. United Airlines brought in about $3 billion more than American last year, and U.S. profit leader Delta Air Lines made nearly $5 billion more.

In an exclusive interview with CNBC late last month, Isom said American and its nearly 140,000 employees want "to be best at everything that we do." He said that carrier's "long-range plan is certainly making up the margin gap," but he didn't put a timeline on that goal.

American's top executives at the carrier's headquarters late last month outlined new initiatives to CNBC: bigger, more luxe airport lounges, a new wide-body aircraft order, and fresh interiors for even more of its long-haul fleet to attract big spenders.

Isom described the carrier's identity as "a premium global airline with the largest footprint in North America."

American has more decisions it needs to make — and soon — to close the gap. Perhaps its biggest challenge is getting customers to shell out more to fly, something Delta and United zeroed in on years ago.

American has mastered running an efficient business but "what we will measure over time is: Are we closing this revenue gap and closing the unit revenue gap?" American CFO Devon May said.

The carrier's executives reiterated that American's plan rests on growing its ever-more important loyalty program, improving customers' experience, expanding its network and increasing higher-end revenue.

The airline is forecast to earn 64 cents a share this year, on an adjusted basis, which would be up almost 80% from last year, according to analyst estimates. It will give an updated forecast when it reports second-quarter results on Thursday.