Abstract: The relationships between the main strut rotating angle and the buffer displacement, and between the main strut rotating angle and the axle incline angle are established for a certain airplane tail landing gear. When the tail landing gear is exposed to weight loading, the axle incline angle is affected by the main strut rotating angle. The turning performance of this airplane is compared with that of the same type of airplane tail landing gear. The reason for difficulty in turning is found to be that the buffer displacement is too great when the tail landing gear is subjected to weight loading, so that the axle incline angle is very large even when the wheel fork is turning a small angle. While ensuring good shock absorption performance, the tail landing gear buffer is filled afresh with higher pressure and less hydraulic oil, which reduces the buffer displacement to zero when the tail landing gear is under weight loading. The axle incline angle is always zero degree after changing the buffer parameters, and the tail wheel remains perpendicular to the ground and the wheel fork is free to run in towing turning and taxing turning in the first flight test even with a small turning radius. Thus, the difficulty in turning is solved by changing buffer parameters.

Key words: tail landing gear, difficulty in turning, main strut rotating angle, axle incline angle, buffer parameters, struts