BEIJING - China's Air Force, the country's airspace regulator, will introduce measures to ease flight delays of civil planes, an airspace regulation expert has said.

The Air Force will shift flights in rush hours to less busy hours, and extend the daily open time of the airspace, said an unnamed official in charge of a national lab on airspace technology on Monday.

The average delayed time of domestic flights was one hour in 2010 and air traffic control, a result of air traffic congestion, was among the major causes of flight delays, according to an official survey conducted last year.

The survey found that air traffic control was responsible for 26.1 percent of all flight delays, which was second to carrier operation and management, which accounted for 42.3 percent of delays.

Military activities led to 7 percent of flight delays, according to the survey.

As part of its efforts to tackle flights delays, the Air Force would make changes to military flights to improve the timely flow of civilian flights, the airspace regulation expert said.

The Air Force would also work with local authorities to shorten the interval time between flights.

The Air Force has announced it will open six military airports for civilian use over the next five years.

According to the expert, the available airspace in China is 9.99 million square kilometers, with 32 percent for civilian use and 23.51 for military use.