Ditching is an aircraft emergency condition that ends with the planned impact of the aircraft against water. Four main phases may be considered in a ditching event: Approach, Impact, Landing and Floatation
This paper addresses some aspects of the second phase, an extreme case of fluid-structure coupling were high pressures may be developed during the impact of the sliding aircraft with water, which in turn may cause rupture of the structure, jeopardizing the required safe evacuation of crew and passengers.
For completeness, the paper recalls a description of the ditching tests performed within the European funded research project SMAES. These tests were first used to derive a synthetic expression of the ditching loads based on rigid plates measurements.
For flexible plates, these synthetic pressures are in turn corrected using local deformation (in terms of local delta-pitch and local delta-z deformation) in an iterative process. When comparing the deformations obtained using Finite Element Method simulation and the corrected synthetic pressures versus deformation measurements, the results show very good comparison of deformation shape time histories, good comparison of time of occurrence of peak deformation in each pick-up and only fair comparison in terms of deformation levels
