The influence of aerodynamic interactions between components on landing gear noise

The design of aircraft landing gears requires careful optimisation for each specific design of new aircraft, to include factors such as the overall size, strength and weight of the gear, the number of wheels, the method of transferring loads to the wing, the drag and, last but not least, the noise of the gear. The aim of the study described here was to generate an experimental database to assist in the design of future low noise landing gears by investigating the influence of a number of design parameters on the noise of the gear. Firstly, factors affecting the noise of the main landing gear bogie are considered, including the number of wheels, the bogie angle, etc. Secondly, the effect of a double sidestay design on the overall noise of a main landing gear has been investigated. Finally, a number of other landing gear design parameters are considered: the effect of a small bogie fairing, an optimised routing for dressings, the effect of yaw angle in the flow. The paper focuses particularly on the effect of various aerodynamic interactions between components which in some cases were found to have a strong influence on the overall noise of the landing gear.