This part of GB/T38924 specifies the test conditions, test equipment and instruments, test process, and test interruption for the waterproof test of the civilian light and small UAV (takeoff weight between 0.25kg and 150kg) systems (including aircraft and ground stations) and recovery, test result evaluation and test reporting. This section applies to civilian light and small unmanned aerial vehicle systems that may be sprayed by rain during use to determine whether the civilian light and small unmanned aerial vehicle system can withstand the impact of rainwater sprayed or dripping onto its surface. .