Why Nearly Half of Asiana Passengers Were Chinese

Seoul has become an important transit gateway for many Chinese travelers connecting to cities in the U.S. and Canada. The reason? Passengers are lured by attractive prices and a dearth of transpacific nonstop flights from China.

This helps explain why nearly half, or 141, of the 291 passengers aboard an Asiana Airlines 020560.SE -0.58% flight from Seoul that crashed at the San Francisco airport were Chinese nationals. Both passengers killed on Saturday’s flight were female Chinese nationals, according to the South Korean Foreign Ministry.

For decades, the South Korean capital has played a key role for passenger travel between Asia and North America Korean Air Lines Co. 003490.SE -0.67%, the nation’s biggest carrier, has for years offered flights to more cities in North America than any other Asian airline, and that remains the case, while Northwest Airlines, which in 2010 merged with Delta Air Lines Inc. DAL +3.20%, operated a major hub out of Seoul until the early 1990s.

But competition for passengers has intensified as many of the region’s airlines expanded their own flights across the Pacific. In China, however, despite surging demand for flights to North America, the nation’s mainly state-owned airlines have been slow to add capacity, thus keeping fares higher. U.S.-China flights are also governed by a highly regulated bilateral treaty, making it less flexible for airlines to increase services as needed.

Transpacific nonstop flights from China mainly originate from Beijing or Shanghai. There is also limited service from the southern city of Guangzhou. This means passengers elsewhere must travel through one of these cities to get to North America.

Airlines in South Korea and Japan significantly boosted their Chinese services in the last few years, in part to cater to the rising demand of transit passenger traffic. Korean Air now flies to some 22 mainland Chinese cities from its Seoul hub, while Asiana operates to 21 Chinese cities, being two of the biggest foreign airlines operating in the country. Meanwhile Japan Airlines 9201.TO +0.94% flies to 15 mainland Chinese cities.

The territorial spat between Japan and China has helped divert more China-originating transpacific traffic through South Korea, according to analysts. Passengers are also attracted by cheap prices offered by many of these airlines.

To illustrate, roundtrip economy fares between Shanghai and San Francisco sell for as low as 4,800 yuan on Asiana Airlines’ website, while a nonstop flight on state-owned China Eastern Airlines Corp. 600115.SH -0.78% could cost around 7,600 yuan, according to the China Eastern website.