February 28th in spring and September in summer 1. Northwestern Polytechnical University, referred to as "Xigong University" for short, is directly under the Ministry of Industry and Information Technology of the People's Republic of China. It is the only national key university in China that features the simultaneous development of aviation, aerospace and navigation engineering education and scientific research. According to the query of official website of Xigong University, under no special circumstances, sophomores in this school start school on February 28th every year, and after the summer vacation, they start school on September 1. However, if it is necessary to postpone the start of school due to special circumstances such as epidemic situation, the specific start time shall be subject to the announcement of the start of school issued by official website.