BEIJING, June 7 -- China's independently-developed AC311A civil helicopter has successfully completed a major plateau sling-load flight test in Lhasa, in the southwestern Xizang Autonomous Region, according to the Aviation Industry Corporation of China (AVIC).

The light helicopter recently underwent this sling-load operation flight test by slinging freight weighing 325 kilograms at a general airport at an altitude of 3,680 meters in Lhasa, said the AVIC, the country's leading aircraft manufacturer.

Lifting and slinging the freight, the AC311A smoothly conducted a series of flight test activities, such as climbing, turning, level flight, and gliding, before landing safely.

During the whole process, the AC311A helicopter showed good flight controllability and stability in plateau conditions, said the AVIC.

The six-seat AC311A is a two-tonne light single-engine civil helicopter.

It has a maximum take-off weight of 2,250 kilograms, a maximum cruise speed of 240 kilometers per hour, a maximum range of 630 kilometers, and a service ceiling of up to 6,000 meters, according to the developer.