Singapore's ambitious project to double its air passenger handling capacity by the mid-2020s is set to extend its lead over neighbors like Kuala Lumpur, Bangkok and Jakarta, whose airports are struggling with congestion and construction delays.
Changi, Southeast Asia's biggest and most popular international airport, is keen to seize a greater share of a boom in regional traffic, mindful of competitors' plans to grow into international hubs.
The increased capacity also plays into the hands of budget carriers such as Malaysia's AirAsia, Singapore Airlines affiliate Tiger Airways, Qantas Airways affiliate Jetstar Asia, which is based in Singapore, and Indonesia's Lion Air.
Low-cost carriers such as these account for a third of Changi's traffic, up from virtually zero just eight years ago, and are hungry to expand routes and flight frequencies.
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The expansion plans, which include a third runway and a fifth terminal by the mid-2020s on top of a fourth already under construction, will double current capacity to around 130 million passengers annually and cement Singapore's leading role as a hub of Southeast Asian business.
Regional traffic predictions point to the need for bold construction plans as airports will have to double their passenger capacity every 12 years just to keep up, said Andrew Herdman, director-general of the Association of Asia Pacific Airlines.
"It's no good thinking in terms of incremental capacity enhancements of terminals or airports or runways," he said.
Driven by growing economies and rising middle-class incomes, passenger traffic in Southeast Asia is expected to rise 7.6 percent a year in the 20 years to 2031, outpacing a global average of 5 percent, according to research firm Strategic Airport Planning Ltd.
Travel between Southeast Asia and South Asia, for example, is expected to grow even faster, at 9.5 percent a year.
"Changi has big growth markets such as Vietnam and Indonesia in its region that it can serve. That can drive demand," said Shukor Yusof, aviation analyst at Standard & Poor's.
Narrow bodies, many flights
The rapid rise of Asian low cost carriers caught much of the airport industry unprepared and led to Changi's decision last year to shut a budget terminal and build a larger one, the T4.