The most distinctive feature of alumarine’s new monohull RHIB range is the “Z” bow. 

This has been a feature on alumarine catamarans for over a decade and is now being incorporated into our monohulls. 

The “Z” bow is a common feature on European pilot boats and in more recent times has started appearing on Australian boats.  The theory behind the Z bow is simple,  it allows the hull to be made longer and finer at the all-important waterline without increasing vessel weight or length. 

The result is a vessel that cuts through waves rather than crashing over them and a smoother ride with less tendency to dive in a following sea.

Along with the Z-bow, these vessels also utilise CTMD’s proven stepped hulls with large vents. 

Stepped hulls are not uncommon in this market place, however, they are often over simplified and as a result can cause in increase in drag at slow to moderate cruising speeds.  Stepped hulls work by distributing the lift required to get a boat on the plan away from just the transom but to an area in front of each step as well.  In order to do this air has to be able to get behind each of the steps or a vacuum will form effectively sucking the boat down onto the water and increasing it’s drag.  On race boats or other high-speed vessel’s this is not a problem as the vessel is often close to airborne and as a result air can get behind the steps.  On a passenger boat that spends much of its time at reduced “cruising speeds” this is not the case.  By incorporating oversize vents in the side of the vessel at each step the CTMD stepped hulls are able to get air behind the steps even when operating in displacement mode.  Thus resulting in more efficient across a range of speeds.