STABILISATION TECHNOLOGY IS ADVANCING AT A RAPID PACE. THE DESIGN AND TECHNOLOGY BEHIND SUCH DEVICES MEANS THE SIZE AND WEIGHT OF THE UNITS IS REDUCING WHICH ENABLES EASIER RETRO FITTING AND INSTALLATION ON SMALLER YACHTS
It’s unusual these days to come across a newly built yacht of, say, 60ft plus, that does not have some form of stabilisation installed. The more interesting fact is that an increasing
number of smaller yachts and boats, even in the 20ft to 30ft plus size range, are enjoying the benefits of a stabiliser solution. For professionally crewed superyachts, today’s scenario is that not only can the mother ship have stability under control, but her tenders, chase boats and shadow boats can enjoy the same kind of calming measures too.
Whether displacement, semi-displacement or full-planing motor yachts, it’s those tall superstructures and high centre of gravity that makes motor yachts more susceptible to the uncomfortable effects of waves, either at anchor, moored in a marina, or when cruising in the open sea. For the industry to continue to prosper, owners and their guests need a level of assurance that their sea-going experience is going to be as comfortable and, ultimately, as enjoyable, safe and successful as possible. Once mainly the preserve of gyros and fins, a number of new and alternative stabiliser solutions have since emerged.
Primarily designed to counter the age-old problem of nausea, leading to full-on motion sickness, stabiliser systems often claim a number of secondary benefits, such as, for example, improved fuel consumption and increased boat speed – the level and scale of which is something for the customer, ultimately, to decide.
Whereupon stabilisation had previously only been available for yachts down to a length of about 60ft / 18metres, today’s wider choice, and the burgeoning retrofit market, has meant that owners of new and used boats, even in the 20ft to 30ft size range, are enjoying the same or similar roll reduction benefit, as for larger boats.
Seasickness and how waves affect a hull
Sea and waves impart six different forces on a hull, namely, heave, surge, sway, pitch, yaw and roll. Of these effects, roll is one of the most influential causes in the case of passenger discomfort. Tiredness often ensues, leading to nausea and, in many cases, full on seasickness.
Roll is exacerbated by the boat’s own inertia energy, the effect of which makes a boat roll even more than the angle of the wave itself. The result is large movements of the head in the form of sudden accelerations from side to side. The boat’s own momentum takes over and increases the sickness-inducing effect even more. The vertical, up and down pitch of a hull has also been highlighted as one of the main causes of seasickness. The logical reality is that it’s more likely a combination of all six effects, with each contributing to a greater or lesser extent.
And, although it’s true that, for many people, the body does eventually regain itself over time and becomes more accustomed to the uneven motions and nausea, getting to this point is without doubt one of the most miserable times for anyone on a boat, when all you simply want to do is get yourself back on dry-land as quickly as possible!
Based upon the simple premise that an upright and properly trimmed hull is working more like its naval architect intended it to do, the other major reason for investing in an appropriate stabiliser system for your hull type, is additional savings on fuel for the kind of typical boating you prefer to do.