A rise in Spanish and U.S. passengers has helped Norwegian Air Shuttle post its best ever quarterly set of results.

The carrier reported a net profit of $122 million – an increase of 19 percent on the prior year with revenue up 15 percent to $1 billion.

Several key airline metrics also saw improvements. Load factor rose by 0.6 percentage points to 91.3 percent while production growth (ASK) and traffic growth (RPK) both improved by 17 percent.

Norwegian is one of the world’s fastest growing airlines and its rapid expansion coupled with tight cost controls is fuelling its impressive performance. So far this year it has taken delivery of three new Boeing 787 Dreamliners and 14 new Boeing 737-800s.

During the quarter it opened services between Paris and several U.S. cities and it also received a boost from its Spanish domestic routes. In total, the airline saw passenger numbers rise by 12 percent to 8.6 million.

“I am very pleased to report Norwegian’s best quarterly result ever and grateful that our loyal customers worldwide continue to fly with us. The overall development is good in all markets, and the biggest growth is in Spain, particularly on domestic routes. The routes between London and Paris and the U.S. are in high demand,” said Norwegian’s CEO Bjørn Kjos.

It hasn’t all been plain sailing for the airline. It has faced criticism for its labor practices but recently said it will start employing U.S. pilots.

Many people in the aviation industry were skeptical when it launched its first low-cost long-haul services in 2013, a model that had previously failed. However, it’s success has forced legacy airlines on both sides of the Atlantic to sit up and take notice.

Next year Norwegian is set to take delivery of its first Boeing 737-MAX, which will enable it to fly between Europe and the U.S. using a single-aisle aircraft, opening up the possibility of offering direct routes between smaller airports.

Photo Credit: A Norwegian aircraft. The carrier reported record results in its third quarter. Norwegian Air