Stratified Sampling Historical Regression Method for Aircraft Precipitation Enhancement Effect Test

To strengthen the objectivity of aircraft precipitation enhancement operation decision-making and effect testing, the operation target area can be determined by the ice saturation, accumulated water vapor layer below 0℃ thicker than 9 mm, and vertical water vapor transport; the operation effect area can be determined by the zone where the AgI particle concentration is greater than or equal to 10 L?1, and the comparison area can be chosen using the operation target area, total precipitation isoline, and related-coefficient test. When the regression equation is established, the weather system types and the same operation period determine the regression samples. An aircraft precipitation enhancement effect test system was established in which one operation uses stratified sample and historical regression in the variable comparison area and influence area. The system has been used in business. The method has clear physical meaning and is important in operation decision-making and effect testing.