During the period from December 30, 2002 to January 5, 2003, the fourth unmanned flight test under the China Manned Space Program was implemented successfully. the backup astronauts also entered into the spaceship for obtaining the actual experience. When the spaceship was flying in the orbit, various instruments and equipment on the spaceship worked normally, and a lot of valuable flight test data and scientific materials were obtained.
As the third formal unmanned spaceship under the China Manned Space Program, the Shenzhou IV spaceship is developed on the basis of the successful implementation of Shenzhou I, Shenzhou II and Shenzhou III flight tasks. Its equipment, function and technical conditions are almost the same as those of manned spaceship. As for this spaceship, the total length is about 7.4m, the maximum diameter is 2.8m, and the total mass reaches 7,794kg. A solar cell wing is installed on the quadrant II and quadrant IV of propelling module and orbital module respectively. The total area of two solar cell wings on propelling module reaches 24.48m2, and the width of the unfolded wing reaches about 17m. The total area of two solar cell wings on orbital module reaches 12.24 m2, and the width of the unfolded wing reaches about 10.4m.
At 0:40 on December 30, 2002, the Shenzhou IV spaceship was launched by the LongMarch 2F carrier rocket from Jiuquan Launch Center. As planned, the spaceship flew in the space for 6 days and 18 hours and flew around the Earth for 108 circles. When the spaceship was flying in the orbit, four Yuanwang space tracking ships distributed in three oceans and relevant ground tracking & control stations carried out continuous tracking, measuring and control for the spaceship. In the space, the spaceship successfully completed several hundred actions, including the unfolding of solar cell arrays, the operation in orbit, the determination of posture, the change of orbit and the orbit maintenance (for two times). At 19:16 on January 5, 2003 (Beijing Time), the Shenzhou IV spaceship accurately landed at the landing site in the middle of Inner Mongolia after completing the pre-set space-related tests. Thus, the fourth flight test under the China Manned Space Program was completed successfully.