An exhibition to display the achievements of unmanned planes was held in Yinchuan City, Ningxia Hui Autonomous Region, on October 23. A number of 19 unmanned planes, including fixed-wing, helicopter, multi-rotors and other types, were on display at the aviation show, and they are mainly used for remote sensing mapping. The activity was jointly sponsored by the Exploration and Development Bureau of Geology and Mineral Resources of Ningxia and Ningxia Remote Sensing Mapping Institute. [Photo: Xinhua]