New Delhi, July 28 - The Indira Gandhi International Airport (IGIA) in the national capital boasts of three well-equipped runways, but flights, including those on international routes, continue to be delayed, especially at night.

Most international flights that operate during peak hours at night are generally delayed ever since the Delhi High Court restricted the use of the third runway (No.29) after 10 p.m.

'Of the three runways at the IGI airport, we can use only one from late night hours till early morning. This is one reason why flights are getting delayed at night,' complained an air traffic controller.

Currently, only one runway (No.28) is used from 10 p.m. till early morning. The old runway (No.27) is undergoing repairs, which will take a few more months.

The Delhi High Court had directed the government in May to take steps to reduce sound pollution after a non-government organisation filed a public interest litigation contending that the noise level was much in excess of limits permissible for residential areas.

The third runway was closed for operations after 10 p.m. after the court's directive.

Nearly 700 flights land and take-off at the airport every day.

Civil Aviation Minister Praful Patel told parliament last week that the air traffic congestion at the airport would end once the new terminal, T3, becomes operational by April 2010.