Breeze Airways on Tuesday said it plans nearly double its network to 77 routes this spring and summer, a massive expansion for the U.S. startup that began flights last May.

The Salt Lake City, Utah-based airline is JetBlue Airways‘ founder David Neeleman’s fifth carrier, one he created to capture travel demand between cities that large carriers weren’t serving. Avelo Airlines, another upstart launched by Andrew Levy, until 2018 United Airlines‘ CFO, also launched last year, targeting underserved U.S. markets.

Breeze and other airlines have been preparing for a strong peak spring and summer travel season after two difficult pandemic years. Now, a surge in jet fuel to a 13-year high after Russia’s invasion of Ukraine is testing them on how much they can expand while costs are climbing.

“It’s not been the easiest,” Breeze’s chief commercial officer, Lukas Johnson, said in an interview.

He said the list of new flights was “slightly smaller” than expected a few months ago and that the airline made last-minute tweaks over the weekend. Executives want to avoid changing the schedule on customers later on, Johnson said.

Still, domestic leisure travel, where Breeze and Avelo have been focused, has been relatively robust compared with international and corporate travel’s sluggish recovery from the pandemic.

Breeze has an order for 80 Airbus A220-300 jets, a model whose fuel-efficiency and range are attractive to airlines including JetBlue and Delta.

Breeze expects to receive about a plane a month from Airbus, Johnson said. It has two in its fleet so far and they’ll start flying in May. The first deliveries have a 36-seat first class, 10 extra legroom seats and eight in standard coach. Later, they will have 12 first-class seats, 45 in extra legroom and 80 in coach.

Breeze started out flying Embraer E190 and 195 jets.

The airline will use the new Airbus planes to fly longer distances: transcontinental flights like Savannah to Los Angeles and Providence, Rhode Island to Los Angeles.

Fares will start at $99 for some of the longest routes such as Las Vegas to Jacksonville, Fla., which Breeze plans to launch in August. Johnson expects those fares will be snatched up quickly.

He said Breeze and other airlines are in a balancing act as costs rise.

“You don’t want to raise [fares] too much because you’re still recovering from the pandemic,” he said.