Evaluation of directional ground stability and control characteristics in crosswind landing for civil airplane based on digital virtual flight

Based on airworthiness requirements of civil airplane, a method for evaluating ground stability and control of crosswind landing based on digital virtual flight is established. With maximum bank angle of airframe and maximum lateral deviation during the landing roll-out as key parameters, and in accordance with the results of pilot-in-loop digital flight simulation, ground stability and control as well as airworthiness compliance of crosswind landing task of a certain large amphibious aircraft were evaluated. Simulation result shows that, for a 20 kts crosswind component, the aircraft conducted a safe and well-behaving landing roll with a 3.44° maximum bank angle and 2.51 m maximum lateral deviation on dry runway, which was of airworthiness compliance. Further research indicates that crosswind component value and the extent of runway contamination significantly affect the safety of crosswind landing roll-out. A 30 kts crosswind component might result in uncontrollable ground-looping tendency on dry runway, while contaminated runway increases landing roll-out distance and brings difficulty to direction control of taxiing. The method delivered in this paper can be applied to the preliminary design phase of civil airplane and offer theoretical references for subsequent flight tests.