Now classifying its Shenzhou spacecraft as operational equipment, not experimental, China launched its fifth manned space mission on June 11.

The objectives of the 15-day Shenzhou 10 mission are to further develop China’s technologies for docking and supporting human life in space, laying the groundwork for the space station that is supposed to be operational around 2020. With Shenzhou 10, the phase aimed at perfecting docking and spacewalking techniques should be complete.

The space station is likely to be launched before 2016, state news agency Xinhua says, presumably referring to the lofting of the first module. The likely masses of the space station modules suggest that the entire effort is awaiting the introduction into service of the Long March 5 heavy launcher, which was most recently due to make its first flight in 2015.

As in previous missions, the docking target of Shenzhou 10 will be the Tiangong 1 orbital laboratory, which is nearing the end of its two-year design life. The Shenzhou crew of two men and one woman are charged with docking with Tiangong, once automatically and once manually.

A Long March 2F, identical to that used for Shenzhou 9 last year, launched the latest mission at 9:38 GMT from the Jiuquan base in the Gobi Desert. The Long March 2F is China’s human-rated rocket, though it also was used to launch the unmanned Tiangong 1.

The Shenzhou craft is no longer considered to be experimental equipment, Zhou Jianping, chief engineer of China’s manned space program, tells Xinhua. Shenzhou 3 carried China’s first astronaut to orbit in 2003.

China conducted its first spacewalk in 2008 with Shenzhou 7 and its first docking in 2011 with the unmanned Shenzhou 8 and Tiangong 1. The Shenzhou 8 docking was automatic; Shenzhou 9 followed with a manual procedure in 2012.

Chinese media emphasize the difficulty that China faces in these missions, because it is limited by the throw weight to low orbit of the Long March 2F, which is less than 9 metric tons.