UPDATE 3-Norwegian Air eyes strong summer, but Danish airport a worry

(Adds detail on Copenhagen airport delays)

By Victoria Klesty

OSLO, May 12 (Reuters) - Norwegian Air is expecting one of its strongest summer seasons ever, but is concerned a shortage of Danish air traffic controllers could lead to problems, the budget airline said on Friday.

The comments, which came as the company reported a loss for its seasonally weaker first quarter, chime with those of rivals as airlines see a surge in demand in the wake of the pandemic but fret about a repeat of last year's disruption at airports.

"Norwegian prepares for what is expected to be one of the company's strongest summers ever," the airline said in a statement, adding that average fares booked so far for the June-August period were up 25% compared to last year.

However, CEO Geir Karlsen highlighted the risks from a shortage of Danish air traffic controllers that has triggered delays and cancellations at Copenhagen Airport.

"We are concerned that there won't be enough staff over the summer," Karlsen said in an interview on the sidelines of an earnings presentation.

Naviair, the company controlling air traffic in Danish airspace, shed 46 air traffic controllers in voluntary layoffs during the COVID-19 pandemic, leaving remaining staff to take additional paid shifts as travel later recovered.

But Naviair controllers in late April began turning down the extra work in a conflict over work hours, leading to delays and cancellations.

"We are following it very closely... Copenhagen is very, very important to us," Karlsen said, adding Norwegian Air and Nordic rival SAS had jointly written to Denmark's government pushing for a solution to the delays.

Karlsen said his company was looking for alternatives for its customers, including moving flights to the nearby Malmoe Airport in southern Sweden.

"For the full-year of 2023, the company is forecasting a significant increase in unit revenue from last year," Norwegian said.

Its January-March net loss decreased to 993 million Norwegian crowns ($94.7 million) from a loss of 1.03 billion a year earlier.

During the first quarter, normally a slow period for holiday travel, the company curtailed capacity by up to 30% to reduce costs.

($1 = 10.4882 Norwegian crowns) (Reporting by Victoria Klesty, additional reporting by Louise Rasmussen Editing by Gerry Doyle and Mark Potter)