Charting a course counter to rival carriers that have jacked up ticket prices for the summer travel season, Spring Airlines, the nation's only budget airline, is planning on offering steep online discounts this Sunday.

A total of 1,000 discount domestic tickets will be sold starting at a mere 9 yuan ($1.33) each and staggered upward from 99 yuan, 199 yuan and 399 yuan. The cheap seats apply to some 28 domestic flights operated by Spring Airlines and will go on sale at midnight on Sunday. These tickets are for travel between Nov 25 and Dec 25 - not including Friday and Sunday flights, the carrier said.

Seven direct flights out of Shanghai are available for 9 yuan each, pretax, and fly to destinations including Shijiazhuang, Hebei province and Wenzhou, Zhejiang province.

Flights from Shanghai to 12 other cities, including Tianjin and Chongqing, will cost 99 yuan each.

Flights between Shanghai and another seven cities will be priced at 199 yuan. Two more flights between Shanghai and Urumqi in Xinjiang Uygur autonomous region and Shanghai and Kunming, Yunnan province, are going for 399 yuan.

"The 1,000 tickets will offer discounts totaling over 300,000 yuan," said Zhang Wuan, spokesman from Spring Airlines. "This is a present to our costumers to celebrate our fifth anniversary," Zhang said.

Michael Peng, sales manager of Shanghai Business International Travel Service, called the idea a great sales gimmick.

"Almost all the domestic tickets are going at full price, and Spring Air is going super cheap," he said.

The ongoing Shanghai Expo has given a boost to domestic air travel, which has also helped Shanghai-based Spring Airlines recover sooner than expected from an industry-wide recession in the past two years.

In the first half of 2010, the carrier doubled its profits to 160 million yuan. Meanwhile, its sales hit 1.47 billion yuan, up 60 percent year-on-year, according to Zhang.

As the nation's only budget private carrier, Spring Airlines' development has received less government support in comparison with its State-owned counterparts, said Li Lei, an industry analyst from Citic China Securities. "But up to now the carrier has performed even better than the top three carriers," he said.

"The success of Spring Airlines is also attributed to its parent company Spring Traveling Agency, which guarantees large passenger flow to the carrier," said Li.

By operating the whole industry chain, Spring Airlines' model sets an example for the future development of private carriers, he added.

The budget airline is scheduled to launch its first international flight to Ibaraki Prefecture, on Honshu island in Japan, on July 28.