The following 4 stability curves - 2 shallow draft, 2 optional fin keel - give examples of the variations in righting arms and points of vanishing stability (PVS) which can occur with different vertical centres of gravity (VCG). The vertical centre of gravity for any given yacht varies with the selection and position of equipment and the final loadings of the yacht. An accurate stability curve is only possible when an inclination experiment has been conducted at a known displacement, and the real centre of gravity is then established.
Attention to detail regarding weight, and positioning of weight, during building and fitting out will help optimise the vertical centre of gravity.
1.5m Shallow draft keel - VCG 200mm above DWL - PVS 129.8deg |
1.5m Shallow draft keel - VCG 150mm above DWL - PVS 134deg |
1.75m optional fin keel - VCG 140mm above DWL - PVS 135deg |
1.75m optional fin keel - VCG 75mm above DWL - PVS 140.4deg |