Hainan Airlines Co., the biggest private airline in China, posted a 16 percent jump in full-year profit as oil prices tumbled, though the gain was limited by foreign-exchange losses.

Billionaire Chen Feng's airline had net income of 3 billion yuan (US$460.6 million) last year, compared with 2.6 billion yuan in 2014, the Haikou, Hainan-based company reported Thursday. The company recorded a foreign-exchange loss of 1.87 billion yuan, 250 times bigger than a year earlier, following a surprise devaluation of the Chinese yuan in August.

China unexpectedly devalued its currency in August, triggering volatility in foreign-exchange markets that has proved problematic for its airlines since aircraft purchases are denominated in dollars. China operators ordered more than US$100 billion worth of aircraft from Boeing Co. and Airbus Group SE last year. The yuan ended last year down 4.4 percent against the greenback, its biggest annual loss since 1994.

Hainan's larger rivals, the three big state-owned airlines, are set to report bigger earnings increases next week, according to analysts' estimates. Mainland carriers have been aggressively expanding their international offerings, and Hainan Air increased its long-haul capacity by 51 percent last year, according to Bloomberg Intelligence analyst John Mathai.

Going Global

Fuel costs decreased almost 32 percent last year, while passenger traffic increased 8.4 percent as the cheapest oil in more than a decade and a no-hedging policy helped carriers in China.

Nationwide passenger traffic rose 11 percent to 440 million trips, according to the Chinese aviation administration, which has projected 485 million passenger trips this year. Chinese airlines now fly direct to 114 long-distance destinations, up 150 percent in the past five years, according to Boeing.

Hainan Air's revenue declined 2.3 percent to 35.2 billion yuan last year as the overall passenger load factor reached 88.2 percent. The carrier has started flights to Chicago and Seattle from Beijing, the hub of Air China Ltd. The airline also expanded its routes from Shanghai, the home of China Eastern Airlines Corp.

To meet the expansion and surge in travel demand, Hainan Air placed an order with Boeing last year for 30 787-9 Dreamliner planes valued at US$7.7 billion. The carrier will take delivery of the first jet under this deal in 2021, adding to Hainan Air's current Dreamliner fleet of 10. It operated a mostly Boeing fleet of 202 at the end of last year.

Buying Binge

Hainan Air's parent HNA Group is on an acquisition spree, having added a 24 percent stake in Brazil's third-largest carrier by market share, Azul SA, last year and wrapping up its US$7.6 billion takeover of jet lessor Avolon in January.

The group was founded in 1993 and its fortunes climbed after the resort island of Hainan --known as "China's Hawaii" -- was designated a province and a Special Economic Zone in 1988. Chen controls Hainan's two main airports, as well as hotels and travel agencies in the province. His company is also the biggest property developer in the provincial capital of Haikou.