Test: Blackdog Cat 5.5SS

By: Norman Holtzhausen, Photography by: Norman Holtzhausen

Blackdog Cat 5.5SS Blackdog Cat 5.5SS
Blackdog Cat 5.5SS Blackdog Cat 5.5SS
Blackdog Cat 5.5SS The transom is simple and clean and features raised battery storage and boarding platforms flanking the engine well. Blackdog Cat 5.5SS
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It's hard to believe just four years have passed since the first Blackdog Cat had us all a-flutter as we took on the surf in a tiller-steered four metre model.

More than 140 of these clever boats (in seven different models) are now in the hands of happy owners around the country. So owner, designer and chief engineer Luke Seuren can feel justifiably proud of the growth of his brand and the track record he has built up with these radical boats.

Each Blackdog Cat shares the same basic hull design – two pencil pontoons providing unrivaled stability and space. Each pontoon, constructed of 4mm marine-grade alloy, contains three independently sealed and pressure-tested air chambers to make these boats arguably among the most unsinkable vessels on the water today.


Space to spare

The 5.5SS is Seuren's biggest model yet, with a cuddy cabin for shelter and a T-top to provide shade. Boasting a hull length of 5.5m and an external beam of 2.45m, the cockpit space rivals that of a 6.5m monohull with room for four to six people. This is undeniably a day boat, with the cuddy providing sheltered storage space for gear and bags but no seating. The T-top is made in the same factory as the hull and folds down for storage.

The cuddy cabin features a walkthrough door, which provides access to the bow for anchoring or beach access. Each pontoon has a flat section, covered in non-slip mat, which could be used when fishing or swimming, but with no bow rails, you're in a pretty tenuous position unless it's absolutely calm. So it's more likely to be used for stepping on or off the boat at the dock.

IMG_1533The 5.5SS has just two seats, upholstered plastic numbers fitted to welded pods. These are non-adjustable but have a movable bolster that swings down from a back-support position to extend the lower part. The pods also provide storage space for small items underneath, while the angle of the pods maximizes cockpit floor space.

The skipper's position is comfortable, with a welded footrest, although I found the seat slightly too far from the steering wheel, but this could be customised to suit. The large flat dash is dominated by the Lowrance HDS-10 colour GPS/chartplotter, a fantastic unit with 3D maps. Electronic gauges for the Yamaha outboard fill the dash, alongside a Uniden VHF. I would have liked to see another grab-handle welded to the hull for the skipper, because apart from the steering wheel, the only thing worth holding onto was the edge of the windscreen.

The deck is aluminum checkerplate, with optional tube mat sitting on top. The pontoons have an additional section welded on top to raise the gunwale height while also providing a generous parcel shelf for loose items. This increased gunwale height provides thigh support when standing, but it's also just right for sitting on and the soft non-slip pads provide comfort.

The black aluminum framed T-top provides shelter from the sun for the skipper and passenger, as well as hosting six rod holders and a mounting point for the VHF aerial. This frame is one of the best designed I've seen and easily folds down by undoing a couple of bolts. This enables the Blackdog to be stored in a normal garage or under a carport.

IMG_1522The transom is dominated by a black bait station, containing a livebait tank accessed by lifting up the baitboard.The starboard side of the transom has the battery storage – lifted well clear of the deck – while the port side gets a storage compartment. A bilge pump tucked under the transom takes care of any water that gets in, although since the deck is just above water height, there shouldn't be much need for this.

The stern of the boat also holds a sturdy black ski-arch, which provides a pair of additional rod holders. There's no step-through to the transom, but it is easy to step over either side and a T-style boarding ladder provides access for divers, although there are no grab handles down low.

Last but not least, is the Yamaha F150 four-stroke siting on the back. This economical and reliable powerplant provides plenty of grunt, and a 120L underfloor fuel tank gives huge range for even the most adventurous day trip. The review boat was painted a startling red, with stunning vinyl graphics draped across the bow and down the flanks.

Not afraid to fly

Despite the morning's fair forecast the wind had built up to a fresh 15–20kt easterly by the time we launched from a private ramp among the ships of Port Whangarei. Our target was Bream Head, some 12nm from the inner harbor, and we could see that conditions were getting progressively worse as we got further out.

By the time we were clear of the harbour entrance and into Bream Bay we had a swell of nearly one metre running and whitecaps coming at us from the stern quarter. In many boats, this means trimming the motor in and slowing down to control the tendency to surf down the waves. In the Blackdog though, the correct response was the reverse – go faster!

So we whipped her up to 25kts and largely skimmed across the wave tops. The ride in this cat is something that needs to be experienced, as the twin hulls trapped air and provided soft landings. Think bouncy castle and you have the idea. There's no crash and bang of a conventional monohull and while the quartering swell did try to rock us, by keeping the speed up we nearly eliminated those effects. The hydraulic steering is very light and responsive and it was no sweat to actively steer from swell top to swell top.

TAB_NZ_238_026-030_Trailerboat _Test _Blackdog -Cat _ASG_BK_JS

After stopping at Frenchman Island for the necessary photos, we headed out to Bream Head. This boat is ideally suited to divers as well as many styles of fishing, and I'd come prepared. Parked in the lee of Mouitaha Island I geared up and the huge cockpit made this very easy. The broad flat gunwales also simplify single-handedly putting on a BCD and dive tank – a task that is a struggle on most boats.

After finding a couple of crayfish that wanted to come home with me, I surfaced to find Seuren and the photo boat had disappeared. Oh, well. Climbing back on board is simple enough, even single-handed, thanks to the low boarding platform and T-style ladder, which means it can be used even with fins still on your feet. I had just finished stripping off my gear and was drying off when an apologetic Seuren arrived back, explaining that he spotted a workup a few hundred meters away and just had to go and throw a stickbait at the massive school of Kahawai. And who wouldn't?

The wrap

Coming back into Whangarei the wind had dropped just fractionally, so once inside the sheltered inner water we were able to put the hammer down. The big Yamaha 150hp jumped forward well in excess of 35kts, with a bit more grunt still left in reserve. This was despite two adults, a nearly full fuel tank and dive gear on board. So I have no doubt the 5.5SS would perform extremely well with a 135hp motor or even the minimum recommended 115hp. But after experiencing the power of 150 horses one might ask, why not have the power in reserve?
Of course, cat hulls behave slightly differently to monohulls, both in terms of motor trim and also the way they lean into turns.

However the Blackdog Cat is the best I've seen, not exhibiting the disconcerting outward heel which some cats display. The hull's ability to handle big water was well proven in our test, and the stability is phenomenal.
Back at the ramp the boat was easily loaded single-handed onto the
custom trailer, thanks to wheels on the guide bars which run down the centre of the hull. It is impossible to go wrong, and after powering onto the trailer, the skipper can lean over the bow and hook the winch up without getting wet.

Even as a self-confessed fan of twin hull boats, this is one of the best I have tested. It is the first boat I have been able to rate a 10 both for handling and stability.

Of course, it is a bit unfair to compare it to a monohull, but hey, life isn't always fair!

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