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Prevailing visibility is an important parameter of normal civil aviation activities. It has obvious practical significance along with the increasing constructions of general aviation airport. In consideration of the existing visibility meters in a single aerodrome, we use three methods to calculate the airport prevailing visibility: median method, graph proportion method and averaging method. We use the existing multiset visibility sensors at the airport to conduct automatic observation of prevailing visibility and use the three methods to study and analyze the multivisibility sensor measurements at daytime and nighttime in Tianjin, Dalian, Hailar, Chengdu and Chongqing for 100 consecutive days. After qualitative and quantitative analysis and comparison, the averaging method is proved to have less measuring error than that of the median method and graph proportion method. The differences in observation principles and observation methods, the number of visibility meters, regional climate, and observation locations are the main factors affecting the data quality of prevailing visibility.