Norwegian Air's first passengers disembark the plane arriving flight from Edinburgh, Scotland, UK, at Stewart International Airport on Thursday, June 15, 2017. KELLY MARSH/For the Times Herald-Record ▲

STEWART AIRPORT – Norwegian Air will discontinue operations at New York Stewart International Airport in September, two years after it almost single-handedly reversed the faltering airport's fortunes with low-cost flights to Europe.

The over-extended carrier, which over the past year has slowly whittled its Stewart schedule to seven flights a week from 27, will fly to Dublin, Ireland, its sole remaining destination, for the last time on Sept. 15.

"As the airline moves from growth to profitability, we have conducted a comprehensive review of our transatlantic operations between North America and Ireland and concluded that these routes are no longer commercially viable ...,'' said Matthew Wood, Norwegian's senior vice president for commercial long-haul and new markets, in a statement.

"Compounded by the global grounding of the Boeing 737 Max aircraft and the continued uncertainty of its return to service," Wood continued, "this has led us to make the difficult decision to discontinue all six routes from the U.S. and Canada to Dublin, Cork and Shannon."

The other routes originate at T. F. Green in Providence, R.I., and John C. Munro Hamilton in Hamilton, Ontario.

"It is disappointing that Norwegian has decided to discontinue service ...,'' the Port Authority, which operates Stewart, said in a statement. "Norwegian's experience (at Stewart) has demonstrated that with the right equipment, market positioning and route map, Stewart has strong appeal."

The Port Authority added that is in "on-going discussions with nearly a dozen airlines, both new entrants and those looking to expand service in the region" but offered no other details.

Norwegian's announcement comes as the Port Authority is building a $37 million addition to Stewart's terminal to create a permanent federal inspection station for U.S. Customs and Border Protection's use in processing international passengers. Norwegian provides the only international flights from the airport.

The Port Authority has always cast the decision to build the addition as part of its ongoing investment in Stewart rather than a Norwegian-centric one. It repeated its commitment to the addition, and its potential role in growing the airport, on Tuesday.

Sean Hughes, a spokesman for Coach USA, said the company had been "privileged" to partner with Norwegian through the Stewart Airport Express and planned to "explore all options as far as moving forward" with the airport.

The bus service between Stewart and the Port Authority Bus Terminal in Manhattan was linked to Norwegian's schedule and viewed as an element of the airline's success. As many as 40 percent of Norwegian's passengers used the service.

Norwegian got a hero's welcome from the time it announced its intent to add European destinations to Stewart's domestic ones in 2016 through its first flight on June 15, 2017 and beyond. By the end of 2018, Stewart's passenger volume had soared to 690,411, a 10-year high, largely on the strength of Norwegian's operations.

The carrier, however, had already begun scaling back its schedule at Stewart and elsewhere amid speculation that its breakneck expansion would push it into bankruptcy before 2018 was out.

The airline got an infusion of capital in a complicated stock transaction in early 2019 and then committed to an aggressive cost-cutting program that further trimmed schedules and closed pilot and crew bases – including those at Stewart. Losses through the first quarter still topped $700 million.

Then, in March, international aviation oversight agencies grounded Boeing's newest aircraft, the 737 Max, after 346 people were killed in two crashes that appeared to involve similar mechanical issues.

The grounding deprived Norwegian of the very planes that it had purchased specifically to serve Stewart and other secondary East Coast airports.

The 180-seat planes had just enough capacity, fuel efficiency and range to allow Norwegian to become a low-cost alternative to the legacy carriers that dominate the transatlantic market.