Question: how does the area under the GZ curve decide how hard a wave slap must hit? The experiment moves the centre of gravity up and down in five steps, measures the roll rate that just capsizes the boat in calm water (with and without damping) and compares it with the energy balance 1/2 I w^2 = W x area. It also searches for the smallest regular beam-sea slope that capsizes the boat, up to the non-breaking limit, and times the recovery from nearly upside down.
Press the button. The current displacement, wheelhouse switch, off-centre load, damping and gyradius are used; only KG is varied.