Investigation of longitudinal dynamics of a small WIG craft in flight over sea Waves

Abstract

The flight dynamics of Wing in Ground Effect (WIG) crafts over sea waves in the layer of Strong Ground Effects (SGE) are complex phenomena. In this article, the longitudinal flight dynamics of a small WIG are investigated, thereby showing a nonlinear dynamic behaviour due to variable aerodynamic coefficients that could be affected by the vehicle flight altitude and other environmental parameters such as flying over short, moderate, and long regular sea waves. Instability regions are analysed and compared to traditional simplified equations of motion for different geometries of waves. Simulations are arranged for variations in both manoeuvre requirements and flying vehicle parameters (e.g. cruise speed and mass moment of inertia). A sensitivity analysis is carried out to evaluate the magnitude of a vehicle's lift coefficient as a function of sea wave length and amplitude in terms of some real-world uncertainty sources. The efficacy of the proposed method is demonstrated through the application of simulations. In particular, it is verified that this method is able to produce more reliable results in satisfying constraints and requirements of the underlying problem.Dynamics of a WIG craft in SGE layer.