BOAT REVIEW Southern Pacific Cormorant 600 RIB

The Cormorant range of mid-sized rigid inflatables combines the best features of two of the most popular boatbuilding technologies in this country – a rugged aluminium rigid hull for strength and performance, and an inflatable collar for comfort, stability and safety.

This is the third, and biggest, of the Cormorant range and follows the successful 500 and 550 models. The brief for the design was for durability, weight reduction and a dry, stable ride with stability at rest.
Although Cormorants have proved popular as yacht club chase boats, the design is intended for all-round use, including fishing, diving and water skiing. With the alloy hull, it is capable of being launched straight off the beach or from a boat ramp – no concerns about scratching a fibreglass gel coat.
The new boat is beautifully finished, to a higher standard than a typical club work boat. The light grey and charcoal tubes are offset by a black powder-coated T-top, with black canvas sun shade, complemented by the matching black Suzuki DF100B four-stroke outboard on the back.
Decks all have the fantastic Marinedeck teak-look finish – it looks very smart and provides a comfortable, non-slip and hard-wearing surface, suitable for bare feet or shoes. Parts of the exposed aluminum hull inside are painted, although the exterior hull and transom are uncoated.

The PVC tubes use Southern Pacific thermo-welds rather than glue for the seams. This process produces a structural joint that’s close to the strength of the original material, and which the company claims will never separate regardless of temperature or UV exposure.
Welds have a further benefit of being smooth with no raised edge to snag on fishhooks or similar. They also allow the designer to incorporate textured panels in suitable locations, such as along the tops of the tubes. The life expectancy of a welded PVC boat in New Zealand conditions is now claimed to be similar to that of a Hypalon vessel, at considerably lower cost.
Southern Pacific’s manufacturing system also allows for the seamless integration of modules into the tubes themselves, rather than looking like they were stuck on afterwards. So, there are a number of Railblaza StarPort fittings positioned around the hull – rod holders, cleats, drink holders and all manner of other accessories. All securely fastened, and easy to move around as required.
This boat’s bow has the bowsprit beautifully melded into the hull under the bow tube, tucking the anchor securely but safely away from the occupants. There is now no risk of damage to the boat or passengers when operating the anchor winch, and there is also little risk of damaging the wharf or trailer when bringing the boat in to shore.

A stainless-steel Viper S series drum winch – tucked into the bow locker – is fitted with 60m of premium, double-braid rope and 6m of short-link chain. A reinforced strip over the bow also allows the deployment of a mooring rope or an auxiliary anchor over the bow tube, with one of those handy Railblaza cleats close by for securing it.
The large centre-console’s windscreen provides shelter for a double bench seat – based on a IceyTek chilly bin. In front of the console unit is a second bench seat, and it doesn’t have any form of wind protection. Other seating options are also available. The powder-coated T-top provides a good amount of shade, although only limited shelter from rain or the elements, and again, other options are possible.
Everything is flush-mounted and fully waterproof at the clean, simple helm station. A 9-inch Garmin Echomap SV provides chartplotter and fish-finder functions, and the Suzuki digital gauge is a dedicated display for the outboard. With NMEA-2000 connectivity, all the engine functions can also be displayed on the Garmin.
A very elegant panel of stainless soft-touch illuminated switches from Bell Marine provide a visual display of the state of all the circuits, and these are easy to operate even with wet fingers.
A Fusion stereo, Icom VHF and the MOB+ man-overboard safety cutout system, are also installed. The large, sealed storage locker under the helm keeps gear dry.
Four rod holders are welded to a curved ski-arch protecting the engine, and a bait board fits over the unit when fishing. The new model DF100B Suzuki four-stroke outboard is right in the middle of the recommended range for this hull and it proved more than adequate for three or more adults and a range of gear on board.

As we have noted with the smaller models in the Cormorant range, it is interesting to see that the tubes fit outside the rigid hull, not on top of them as with many RIBs. This gives the boat extra internal beam, especially in the forward area, and there is plenty of space to step around either side of the centre-console.
After launching the boat at Auckland’s Westhaven Marina we headed for the upper harbour. Rather than welded strakes which create drag, this hull features pressed strakes to lift the boat clear at speed, and the pontoons are clear of the water when running in a straight line.

What they do provide is a wide downturned chine to direct spray well out and away from the boat, while in a very tight turn those pontoons provide the unrivaled stability for which inflatable boats are known.
The Suzuki pushed the 6m hull to over 30 knots, although we did not test maximum speed or fuel economy. Open boats tend to be driven according to the conditions, rather than to maximum capability, so top speed is less important than the ability to get off the mark quickly and stay dry in rougher conditions. Both of which this hull does very well. And the 120-litre underfloor fuel tank provides more range than could reasonably be required of a day boat.
Back at the wharf the boat slipped easily onto its un-braked, galvanised trailer. Dry hull weight is a mere 220kg excluding engine – so the estimated towing weight (including fuel, trailer and engine) is under 750kg – an easy towing proposition for even a modest family car. The T-top can be unbolted at around the height of the console and lowered to fit under a carport or garage.
Overall this is a well-presented, family-sized RIB suitable for a variety of roles. The aluminium hull will withstand plenty of abuse, while the safety of the inflatable tubes is a reassurance in rough conditions.
PVC OR HYPALON?
Inflatable tubes are generally made from one of two materials: Hypalon (the commercial name for CSPE synthetic rubber, also called CSM) or PVC. Hypalon is generally touted for greater durability versus PVC’s lower cost but shorter life. But this is no longer necessarily the case.

Hypalon was invented by DuPont, and features resistance to chemicals, temperature extremes and ultraviolet light. For the past decade Hypalon has been the material of choice for high-end inflatables due to its durability; but its greater weight and higher cost (both the material and labour costs, since the gluing process is more involved) makes a boat made of Hypalon more expensive than a PVC boat.
PVC is cheaper and easier to glue, but has been associated with poor UV-resistance – and the tendency for the glue to weaken over time. Early materials were also prone to puncture.
But the quality of PVC material has increased steadily, and Southern Pacific uses a high-quality product from Germany’s Mehler. The Valmex fabric has a high abrasion and puncture resistance and is temperature- and UV-resistant.
With the thermal welding technique used by Southern Pacific, the PVC tubes should last as long as those made with glued Hypalon.