Delta Air Lines is unblocking its middle seats in May, marking the end of social distancing on all U.S. carriers and signaling a turning point in pandemic-era travel.

The Atlanta-based airline will begin selling every seat on its airplanes on May 1 and is reintegrating a number of pre-pandemic features of air travel.

For consumers, these changes signal a return to more of the in-flight experience they knew before the pandemic.

For Delta, they represent the potential of a sudden increase in revenue it seeks to end losses and reach a financial break-even point.

But said Delta CEO Ed Bastian, "Don't confuse these actions with a return to 'normal.' We're still operating in a pandemic, and many of the changes we've made over the past year, such as strengthening our cleanliness protocols and eliminating change fees, will be permanent."

With the seat change, Delta also said Wednesday it will reintroduce a scaled-back version of its in-flight food and beverage service, with mini-cans of Coca-Cola products and premixed cocktails.

The airline said it received advice on food from Minnesota's Mayo Clinic, which has advised it throughout the COVID-19 crisis.

Delta's airport lounges will gradually reopen and expand their food and drink options beginning in May through July.

Masks will continue to be required for passengers, and crews will continue to enforce that.

Delta, the dominant airline at Minneapolis-St. Paul International Airport, marketed itself early on in the pandemic as the health-and-safety airline in hopes of earning customers' loyalty. It blocked off middle seats longer than any other airline.

But with the COVID-19 vaccine distribution gaining momentum, public sentiment about air travel is shifting and bookings are rising.

For a typical domestic flight, selling middle seats could quickly increase Delta's revenue by nearly 50% without adding costs.

"It's the least expensive and least risky option because there's no one else out there keeping middle seats open," said Bob Mann, a Port Washington, N.Y.-based airline consultant.

This could help Delta eliminate its daily cash burn sooner. Two weeks ago, Delta executives told investors that the airline was making progress but would likely end its March quarter burning between $12 million and $14 million a day.

"As demand continues to return and as we release those [middle] seats into the future, that's going to be an incredibly strong lever for us with very minimal cost to open those seats up," Glen Hauenstein, president of Delta, told investors.

Delta expects its capacity — industry parlance for number of available seats sold — will be down about 15-20% this summer compared to the June-August time period in 2019.

At MSP, one of its three largest hubs, Delta is flying about 280 daily flights compared to the 500 it was operating before the pandemic.

The airline said it is adding about 10 daily flights in May and expects to add about 40-50 additional daily flights for summer. As demand accelerates, the airline said, it expects those numbers to rise.

Minneapolis-St. Paul has long been one of Delta's business travel strongholds, but business travel is expected to return more slowly than leisure — likely after most people are back working in offices.

"Business people at least have to go back to their offices before they start to travel [for work]," Mann said. "And then borders have to reopen."

Only about 20% of Delta's corporate travel has returned, Hauenstein said two weeks ago.

Executives hope business travel will rise in the fall with international travel returning in 2022.

Kristen Leigh Painter • 612-673-4767