Delaware is now the only U.S. state lacking regularly scheduled passenger airline service in the wake of Frontier Airlines' sudden pullout from New Castle Airport this summer.

According to Scott Goss of the News Journal of Wilmington, the Denver-based carrier was the only one serving New Castle, but hadn't offered service from the airport since April. 

"Frontier has pulled out of [New Castle Airport] because it wasn't a profitable operation," said company spokesman Jim Faulkner in an email via the News Journal. "If market conditions change, we may look at it again in the future."

Director of Airports Stephen Williams said the Delaware River & Bay Authority is "disappointed with Frontier's apparent decision not to return to [New Castle] Airport."

"We want to thank our customers for choosing [New Castle] Airport and we appreciate Frontier's willingness to initiate service at our airport in 2013," he added.

Despite the disappointment, the move hardly comes as a surprise to Delaware Economic Development Director Alan Levin. "Truthfully, they did not make a firm commitment to the service," Levin told the News Journal. "When you continue to change your offerings, people will lose faith in what is being provided. When I book a ticket, I want to know I'm going to be getting on a plane without the flight being canceled."

Williams told the News Journal that he remains confident that regularly scheduled service at New Castle is "both viable and attractive," citing U.S. Department of Transportation figures revealing promising passenger counts. 

"We continue to explore other opportunities to attract and retain scheduled commercial air service to ILG, and we will be ready to accommodate those airlines when they come," added Williams in an email via the News Journal. 

Frontier's exit from New Castle has coincided with its expansion at nearby Philadelphia International Airport, which is located roughly 30 miles to the northeast along Interstate 95. Recently added destinations from Philadelphia include Minneapolis/St. Paul and Charlotte, among others.

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