Motivated by the dynamics of a trimaran, an investigation of the dynamic behaviour of a double forcing parametrically excited system is carried out.Initially, 30" Warming Drawer we provide an outline of the stability regions, both numerically and analytically, for the undamped linear, extended version of the Mathieu equation.This paper then examines the anticipated form of response Gamma Amino Butyric Acid (GABA) of our proposed nonlinear damped double forcing system, where periodic and quasiperiodic routes to chaos are graphically demonstrated and compared with the case of the single vertically-driven pendulum.