China's ultra large unmanned submarine drones have reached the largest sizes worldwide and were developed for regional security and environmental monitoring missions. The HSU001 and AJX002 models, showcased at last year's military parade, are approximately 20 meters long, and a secret variant exceeding 40 meters revealed in satellite images also drew attention. These developments have raised new concerns especially regarding the defense of the US West Coast. However, Yan Zheping from Harbin Engineering University stated that the primary purpose of these ultra large drones is regional defense and civilian research. In Yan's article published in the China Ship Research Journal, it was emphasized that these drones are mainly designed to balance US operations against possible military situations in the Taiwan Strait or the South China Sea. Additionally, it was stated that China's new generation mega drones will be equipped with mini nuclear reactors, quantum and neutrino communication systems, and will use fully autonomous artificial intelligence and multi-sensing technologies. Yan noted that there are high technical challenges and financial risks in developing these technologies, but this reflects China's strategic determination and industrial capacity.