Stability and Style Aplenty

Supercat Sliver 29

By Erwin Bursik

SUPERCAT Marine’s Dennis Schultz, who I have known since the earliest days of SKIBOAT magazine, first introduced me to his range of ski-boats when I tested his Supercat 620 off Port Alfred on the banks of the Kowie River.

His innovative ideas captured my attention then, but it really boggled my mind when he asked me to do a review on the Supercat 38 Sport, an 11.6m displacement bitech hull that I was told could do 20 knots powered by twin 50hp motors. He also asked me to test the Sliver 29 that followed.

My introduction to the craft in the marina was great, but as I took the helm and pointed her hull into the big waves rounding the western breakwater of the Kowie River, my faith in Dennis and the two 50hp outboards powering Stiletto took a huge nose dive. All I remember to this day is Dennis standing next to me at the helm and reiterating that I must keep her straight bow-on to the sea, and saying, “Don’t touch the throttles!” We exited perfectly with oncoming waves seeming to rush through the craft’s tunnel without any major upward lifting of the bow.

Now it’s 20 years later, and during the intervening years I saw a sportfishing model of the 38 Sport, Castle Lager, very effectively fishing the waters off the north Kenya coast from Watamu.

The first 29ft Supercat, Sliver 29, was bought into production in early 2007, and I reviewed her in the November/December 2007 issue of SKIBOAT. That craft was powered by twin 40hp 4-stroke outboards that maxed out at 21 knots at sea.

With Dennis’s two sons, Neil and Clinton, having taken over the helm of Supercat Marine under the advisory eye of the old seadog, Dennis, a number of changes and innovations have been implemented. One of these was the redesign of the Supercat Sliver 29’s deck layout.

The original Sliver 29 had a raised deck in the large helm station area, thus providing more headroom in the below-deck accommodation and storage areas. Whilst this boat was popular in areas such as the Moçambique islands, the Seychelles and even the Bahamas, the South African sportfishing market tended to look for more fishing-orientated craft with less emphasis on the accommodation requirements. With this in mind, the Sliver 29 was re-designed.

Supercat Marine’s Neil Schultz

Having the fishdeck and wheelhouse on one level the way it is now makes it,in my opinion,much more user friendly and gives her a much more streamlined appearance.This craft will be based at Port Alfred and her owner is looking forward to fishing in the waters off this Eastern Cape harbour.

Once I was behind the wheel of the Sliver 29 and enjoying her performance on the waters of the Kowie River,I very quickly began to appreciate the new design of the helm station itself and also the easier access to the aft fishing deck.This is a great benefit when,for example,and as so often happens when fishing a craft of this size,the skipper has to leave his helm station and quickly move aft to either sort out a tackle problem,gaff a fish or even take a bending rod.It’s all so much easier on this new Sliver 29.

As I stated in my review of the Supercat 590 Multisport (November/ December 2021 issue of SKI-BOAT),I was very disappointed that the mouth of the Kowie River was virtually barricaded with a sand bar that,during the then low spring tide,made it impossible to attempt an exit to sea in a craft of this size.One also has to accept that as the Sliver 29 has a displacement hull,it doesn’t jump up into the plane like many of the planing hull ski-boats we are used to.Any ability to plane across the sandbank and through a break in the waves that may have become possible with other boats would have been impossible with the Sliver 29 as the below water design of her twin hulls is designed to cleave water and not bounce over a sand bar.

I was thus precluded from taking the redesigned Sliver 29 through the surf and experiencing once again the incredible feeling I had last time of seeing a rolling surf building up in front of this craft’s bow and hearing Dennis’s voice in my ear.On that occasion,with great apprehension to put it mildly,I saw how the bows sliced into the cresting wave and watched the wave build up in the tunnel and slip aft,with almost no upward thrust of the craft’s bow.With very little of this “bow up”or jumping of the craft,its forward trajectory is not slowed down.After the first wave I took,and thereafter a second, we were out to sea with our speed over ground hardly retarded.

Whilst I missed the “kyk weer”of my previous Sliver 29 launch,this time I was able to place the bow of the craft I was skippering into the big broken water that was smashing over the sand banks and colliding with the strong outgoing tide of the Kowie River.During the exercise it was incredible to note just how little this turbulent water affected the lateral and fore-aft stability of the Sliver 29.

At one point I had both Suzuki 60hp 4-stroke motors in strong reverse,holding the craft against the outgoing river water whilst facing the very “angry” oncoming waves.It was impressive. Then,using forward reverse on the two Suzukis I was able to turn the 29ft craft 180 degrees on her axis to escape the washing machine of turbulent water, and power upstream in the protection of the wide Kowie River.

Again I must reiterate the incredible performance of these two low horsepower motors and that of the twin 40hp motors on the previous Sliver 29 I tested.It’s really unbelievable when one thinks that on a conventional 30ft skiboat — monohull or cat — a minimum of 2 x 200hp outboards would be required for surf operations.

Whilst doing speed trials on the river it immediately became apparent that there is no “jumping out of the hole and onto the plane”as one expects on any craft with a planing hull.A displaced hull cuts through the water, maintaining its stationary profile and flotation waterline,just incrementally increasing SOG with increased throttle application.

Exact speed/RPM comparison undertaken naturally varied as the Kowie River was running fairly strongly on the outgoing spring tide.With little or no wind on the river,the approximate data I was able to ascertain was 8 knots at 3000rpm,and 13 knots at 3800.She topped out at 21 knots at 4500rpm.Any increase in rpm over that didn’t result in any greater SOG.

Much of the internal layout of the Sliver 29 is as a result of Dennis’s experience taking the original 38ft Sport on a month-long excursion from Port Alfred up to Moçambique’s Bazaruto archipelago.The original Sliver 29 incorporated many of the niceties and/or necessities he determined were required at that stage.Some of those features have now been sacrificed to make the latest version of the Sliver 29 more practical as a sportfishing craft that will be used for day trips off our South African coast.

As I mentioned earlier,the craft I reviewed will be used primarly for angling,thus changing the overall emphasis from cruising to fishing.This, to be honest,aligns with my thinking as — for a fisherman at least — the fishability of the craft is more important than the cruising live aboard aspect.

Having put the Sliver 29 into the rough stuff that was boiling in the mouth of the Kowie River where it passes between the east and west piers,I was totally confident and very impressed with the way this craft could be manoeuvred while having the turbulent undercut waves bashing into her at all angles.It’s not easy to describe, but whether those waves were taken head on,on her forward bow,or side on,she seemed untroubled,and with her lateral stability inherent I had no qualms when playing with her in this rough and confined waterway.

When I positioned her to take the broken wave on her transom,I noticed that the aft lift was negligible and didn’t force the bow region to dig into the water.Instead,the craft seemed to use its inherent flotation to lift the bows to enable her to glide forward rather than digging in as one would expect with a conventional planing hull of the same size.

Throughout my review of the new Sliver 29 I really appreciated the changes to the saloon area and having the wide,flat deck area right to the transom.This open deck configuration not only improves the craft’s fishability, but also encourages the crew to be more centrally situated and closer to the skipper.With the older model they tended to say right aft next to the rods so they had quick access while fishing. Now a crew member can stand next to the skipper and be at the rods in seconds without having to climb around and down from the raised helm station of the previous model.

I personally enjoyed the helm station’s accessibility,visibility and comfort,with all the necessary instrumentation,throttles and steering positioned for maximum skipper comfort.

Whilst the entire helm station is designed to accept the installation of clears,at the time of the review they had not yet been fitted.From a personal preference point of view,I enjoy clears because they offer protection from adverse weather and also improve the ride and stability of most craft.

For those unfamiliar with this craft, the below deck configuration of the new Sliver 29 still has the single sleeper accommodation in the forward section of each sponson.With its three ton load capacity,there are a number of variations that can be incorporated in line with an owner’s requirements.The craft I reviewed certainly had everything I would want for a day’s fishing off any port on the South African coast, all stylishly finished.

I took a long and close look at this craft’s finishes because for many years I have only observed Supercat Marine’s presentations from a distance.I was extremely pleased to see that Neil and Clinton are continuing in Dennis’s footsteps,not only regarding the superb finishes,but also the extra ideas and hardware incorporated to make this craft an extremely well finished and well presented craft.