The friction characteristics of the main runway at the Chennai airport is within the accepted level. This is the certificate issued after a test conducted on June 22. Friction test is conducted to check whether the aircraft landing is smooth. Airports Authority of India (AAI) officials said conducting friction test is essential during rain.

This will help pilots take critical decisions while landing, they said.

Friction test is done once in six months.

A specially designed vehicle is used for conducting the test, which would be operated at a particular speed.

The vehicle would be taken to different parts of the runway.

The test is done on the runway at three metres from both ends of the runway, say officials.

The test was conducted at both on the Pammal and St. Thomas Mount sides.