Dense smoke from massive forest fires in Borneo and Sumatra is severely disrupting air transport across much of South-East Asia, forcing the closure of some smaller airports and the cancellation or delay of many domestic and regional flights.

A thick haze generated by the fires has blanketed Brunei, parts of Indonesia, Malaysia and Singapore since early September, badly restricting visibility. The smoke, which has been exacerbated by a drought and a lack of strong winds, has begun to spread to the Philippines and southern Thailand.

Pilots have reported that the haze typically extends to an altitude of 8,500ft (2,600m) and in some cases 11,000ft, while visibility on the ground has been reduced to as little as 200-300m. The east Malaysian states of Sarawak and Sabah have been among the worst-affected areas, suffering an extended closure of main airports at Bintulu, Kinabalu, Kuching, Miri and Sibu.

Malaysia Airlines (MAS) and Royal Brunei Airlines (RBA) have curtailed services as a result. MAS has been cancelling up to 30 flights a day from Sabah and Sarawak to the Malaysian peninsula and other regional destinations, including Hong Kong, Manila, Singapore and Taipei. RBA flights to Malaysia have also been cancelled.

Elsewhere in South-East Asia, flights out of Singapore have been disrupted, particularly those of Singapore Airlines and MAS to Kuala Lumpur, and SilkAir's services to Padang and Pekanbaru in Sumatra. Singapore's Civil Aviation Authority says that about 70 flights were cancelled and a further ten delayed at the country's Changi International Airport between 20 and 24 September.

As the smog spreads north, services in southern Thailand and the Philippines have begun to be affected. Thai Airways International has been forced to divert or delay domestic flights to Renong and Surat Thani, while Philippine Airlines has cancelled services from Manila to Puerto Pincesa and General Santos in Mindanao.

Source: Flight International