All planes leaving and landing at the Beijing Capital International Airport (BCIA) must use English in wireless communication with ground controllers from May 5 in 2010, aviation watchdog said on Tuesday.

At least 30 percent of the flights must switch from Chinese to English from May 5 this year and no less than 60 percent must do that a year later, the Civil Aviation Administration of China (CAAC) said in a statement on its website.

"Many foreign airlines have complained they couldn't precisely judge their planes' position in the air because of failing to understand the talk between Chinese pilots and air traffic controllers in their mother tongue, which led to hidden safety problems," the statement quoted CAAC deputy director Li Jian as saying at a conference.

He said the problems might worsen as airlines were expected to add flights to Beijing after Terminal 3 was opened in the run-up to the Olympic Games.

The move was also an answer to requirements by the International Civil Aviation Organization for English competence of pilots and air traffic controllers to be upgraded, said Li.

The measure would be promoted to other international airports in the country, according to the statement.

From May 5 this year, crew members on new air routes or new flights to Beijing must be qualified in English, it said.

The BCIA's Terminal 3 went into full operation on March 26, expanding the airport's capacity to 1,700 flights per day, up from 1,000.

The airport handled 53.47 million passengers last year, putting it among the world's 10 busiest. It was expected to receive 5.56 million people during the Games in August.

(Xinhua News Agency April 16, 2008)