The current lateral ground loads requirement, FAR25.495, for an aircraft during a high-speed turn, was written in the middle of the last century, when relatively small aircraft with tricycle landing gear arrangements started to emerge. This requirement is known to be conservative when applied to large modern passenger aircraft. Nonlinearities (such as tyre forces) have a significant effect at the edge of operating envelopes, placing a renewed interest on analysis methods that can classify the dynamics in these regions. In this paper we use continuation methods to assess the loads that can be generated for different aircraft configurations during high-speed turns, and compare the results to the original requirement. A comparison is made between test results from an FAA study and continuation results, where all the significant test data points are located within an envelope constructed from continuation analysis. Continuation methods therefore provide a conservative estimate of the maximum lateral load factors. These values are however less than the value prescribed in the regulation.
|Publication status||In preparation - 1 Aug 2011|