Executives in the aviation and tourism industries have called on the government and Airports of Thailand (AOT) to work together more closely to maintain Suvarnabhumi Airport's safety standards after two sinkholes were found on the west runway on Thursday night, causing delays.

Sisdivachr Cheewarattanaporn, president of the Association of Thai Travel Agents, said the problems at the airport would hurt foreign travellers' confidence if they were not solved.

"The government should have clear measures to take care of the airport and air traffic in cases where unexpected situations arise,' he said, adding that news of problems at the airport circulates around the world quickly, hurting the country's image.

AOT closed the west runway from 8.30-9.30p.m. on Thursday night for repairs after two sinkholes were found. One was 60cm wide, 60cm long and 5cm deep. Eleven flights were affected, seven of them Thai Airways International (THAI) flights, which were forced to delay their landings. Four other flights were diverted to U-tapao, Don Mueang and Chiang Mai airports during the closure.

Suvarnabhumi Airport general manager Somchai Sawasdeepon said the sinkholes on the west runway were caused by water leaks. Although they were not in an area that could cause rutting, the airport immediately closed the runway for repairs.

"The west runway was closed for repairs 209 times last year, and has been closed 55 times since the beginning of 2012. The east runway has been closed 66 times. Every shutdown is for a different length of time. Mostly, repairs were needed to existing cracks," Somchai said.

He conceded that the latest incident had delayed flights and damaged the airport's image. However, he pointed out that maintaining safety is more important than preserving the airport's image.

Meanwhile, the east runway is still closed for repairs, which are scheduled to be complete on Aug. 9.

On Jun. 22, the airport's control tower was hit by a power outage, affecting the takeoffs or landings of nearly 50 flights. Suvarnabhumi is also struggling with a passenger load of 51 million passengers a year, compared to its official capacity of 45 million.

Airlines have reported only a marginal impact, and that the problems are largely under control.

Yongyut Lujintanon, sales and marketing manager for Thailand and Myanmar of Cathay Pacific Airways, said only one Cathay flight was affected on Thursday night. The Hong Kong-Colombo flight was on a stopover in Bangkok. The aircraft was required to circle for half an hour before landing. Yongyut said the airline was able to speed up its ground procedures to delay its departure to Colombo by only 20 minutes.

"Fortunately, the problem was minor," he said. However, he urged the agencies involved to keep the airport's operations to a high standard.

AirAsia's public relations department confirmed that about four of its flights were hit between 8 and 9 p.m. They circled above the airport before landing. Cabin crew communicated with passengers regularly to ensure they understood the situation and the passengers had no problem with it, the firm said.

Woranate Laprabang, managing director of THAI Smile, a business unit of national carrier THAI, said the airport's runway problems are routine if fixed in time. Imagine 100- to 200-tonne aeroplanes taking off and landing continually every day; the runway is sure to sustain damage, Woranate said. At present, runways at international airports in Kuala Lumpur and Singapore are also closed for repairs, the THAI Smile executive said.

He confirmed that THAI Smile's maiden flight to Macau today would proceed. TG750 departs from Suvarnabhumi at 7.45a.m. and arrives in Macau at 11.30a.m.