Landing Gear/Soil Interaction Development of Criteria for Aircraft Operation on Soil During Turning and Multipass Operations.

摘要

The continuing design and operational requirements for military aircraft to operate on unimproved runways has led to the need to investigate those landing gear/soil runway parameters which most significantly influence performance. This report summarized those activities accomplished during the second year of a two-year research effort concerned with the development of criteria for turning,operation at high speed,and multipass operation. The work reported was conducted in several areas. The turned tire test data was completely analyzed and predictive equations incorporated into the turning program. A limited parametric study was conducted for three classes of vehicles to calculate wheel force ratios as functions of runway width required. A multipass test program was conducted at the Army Engineers Waterways Experiment Station to measure the response of rolling and braked tires in alternating paths. The data was reduced and predictive equations evolved from rut depths as a function of first pass response and subsequent path and braking. Limited start-up force data were examined to determine a preliminary estimate of start-up drag ratios. A soft tire/soil computer program was developed to study roughness effects.