Low temperature characteristic analysis and enhancement of hydraulic system on high-altitude and long-endurance unmanned vehicle

Compared with other aircraft types, the operating ambient temperature of high-altitude and long-endurance unmanned vehicle is much lower. This paper addresses the low temperature characteristic of hydraulic system on a high-altitude and long-endurance unmanned vehicle. Some enhancement methodologies are discussed and a self-cycle heating method is recommended to improve the low temperature performance of hydraulic system. The experiments show that the analysis and enhancement methodology is reasonable and effective.