Research on the analysis method of dynamic characteristics in icebreaking for the typical landing gear structure of amphibious aircraft

This study presents a methodology for analyzing the dynamic ice-breaking characteristics of the typical landing gear structure of an amphibious aircraft. It addresses the research challenge of potential icing on landing gear surfaces when amphibious aircraft operate in low-temperature freshwater and seawater environments or encounter atmospheric supercooled water. The study measured the adhesion strength of ice on landing gear structures under various temperatures and salinities. It analyzed the dynamic ice-breaking characteristics during the aircraft’s landing gear lowering process, integrating the ice release criterion. The model’s accuracy was confirmed through kinetic simulations and experimental comparisons between ice-covered and ice-free landing gear during lowering. The study reveals significant variations in ice adhesion strength with respect to temperature, salinity, and substrate material within the range of −10 °C to −50 °C. Specifically, the highest adhesion strength of freshwater ice to lacquered surface structures was observed at −20 °C. The adhesion strength increased with decreasing temperature for freshwater ice on unlacquered surfaces, while the trend remained consistent for seawater ice on both lacquered and unlacquered surfaces. The adhesion strength trends for ice on both lacquered and unlacquered structures exhibited a negative correlation with water salinity levels. Additionally, lower locks of the landing gear jammed when covered with 12 mm of freshwater ice. Freshwater ice also significantly interfered with the landing gear lowering process compared to seawater ice. The maximum equivalent force exerted on the upper and lower stop surfaces by freshwater ice during the locking process was less than 50 MPa, which could potentially cause stalling. In contrast, seawater ice could withstand forces up to 11.02 MPa before breaking. The study provides a significant basis and reference for designing landing gear for amphibious aircraft operating in icy conditions.