• With 200 horses obediently restraining themselves, we burble out of Salterns for a 6-knot potter towards our start line …
  • … even without any direct control over trim, the 520 runs unerringly flat and fast, lifting high on the straight, carving hard in the turn …
  • … it is plain that this boat is optimised for active family sports ahead of mere people-moving duties.
  • … at pace on open waters, its dynamic manners are every bit as impeccable as the reputation Williams have taken such great pains to build.

Alex Smith takes a tour of Poole Harbour on the flagship plaything from the new Williams Sportjet line.

What springs to mind when you think about Williams Jet Tenders? Maybe it’s the jovial British brothers, Matt and John Hornsby, who founded the company? Maybe it’s Theo Paphitis, the Dragon’s Den star and one of the brand’s most famous patrons? Or perhaps you imagine the glitzy superyachts that always seem to go hand in hand with these craft at international exhibitions? Whatever the name now inspires, it’s becoming all the more difficult to remember a time when Williams Jet Tenders weren’t at the forefront of the market – and for a company that only emerged in its current form around a decade ago, that’s a remarkable feat.

Today, the Oxford-based jet tender specialists offer three product lines. Two of them (the Dieseljet and Turbojet) have already achieved world renown as servants to larger craft; but with the third and most recent line, Williams are aiming to offer something a little different – namely, a dynamic stand-alone craft for those of us without a larger mother ship. Known as the Sportjet, it currently comprises just two boats, the 460 (a five-man 15-footer with 150hp) and the 520 (a six-man 17-footer with 200hp). And it’s the larger of these craft that now awaits us at Salterns Marina.

Five famous islands

The start-up procedure on the Sportjet 520 is a rare treat. You turn the key to the right, watch the dials and digital read-outs kick into life with lights, beeps and swishing needles, and only then do you hit the ‘START’ button. The engine ignites with a throaty snarl and the fact that you’re on the most aggressive performer in the Williams fleet is emotively affirmed. Of course, this crowd-pleasing ignition is no more effective than a simple key, but the theatre of the operation is no less welcome for that. In fact, if they could go a step further and replace the flaccid yellow button with a backlit crimson affair, the garish melodrama of the moment might prove even more memorable.

In any case, it’s time to wipe the juvenile smirk off my face and concentrate on what I’m doing. After all, this is £40,000 worth of jet boat with just 10 hours on the clock and these are not waters with which I am familiar. We do, however, have a plan and its simplicity is right up my street. We aim to start at the marked channel through South Deep and run clockwise from the harbour entrance on a tour of the region’s five primary islands: (1) Brownsea Island (owned and run by the National Trust and by far the largest in the harbour); (2) Furzey Island (property of BP and home to a neatly concealed oil pump); (3) Green Island (privately owned by Edward Iliffe since 2005); (4) Long Island (out of bounds since its purchase by a property developer in 2010); and (5) Round Island (privately owned but open to visitors through the rental of a holiday cottage). With 200 horses obediently restraining themselves, we burble out of Salterns for a 6-knot potter towards our start line …

Ship to shore?

Despite our best-laid plans, it quickly becomes apparent that getting ashore is not as easily achievable as I had hoped. Every beach we come across is lined with ‘NO LANDING’ signs, to such an extent that the whole affair rather whiffs of aggression and overinsistence. In any case, this area of Poole Harbour exhibits quite shallow gradients, which makes beaching (or indeed swimming) quite a muddy exercise. Long Island, for instance, apparently expands in size from less than 10 acres to more than 30 between high and low water – and that’s with a tidal range of well under 2 metres.

As for man-made landing sites, by far the most welcoming is Pottery Pier on the western edge of Brownsea Island. Trouble is, it’s currently falling to pieces and has been equipped with a sign warning punters to steer clear. Having spoken to the National Trust about this, I can confirm that there’s no immediate plan to fix it, so if you want to land on Brownsea Island, you need to head round to the south side and either anchor off and wade ashore or pick a sensible spot on a favourable tide and nudge up onto the shale. With beautiful views, good walking, attractive beaches, plenty of wildlife and a castle, it remains an enjoyable stop despite the effort involved.

Elsewhere, the landing stage on the north-eastern edge of Green Island (and indeed those of the other three islands) are all private, so in order to make use of them, you need to get in touch with the owners to obtain permission – and prepare yourself for the fact that the response may well be ‘No’. However, don’t despair, because while direct land access can be problematic, mooring and anchoring is a much more accessible pursuit …

There are particularly good anchorages in parts of South Deep and also in Blood Alley Lake beneath Brownsea Island. But for me, the best spot is in the channel behind Round Island, on the short run south from Shipstal Point. Here, the navigable channel comes to an end at the Round Island jetty, so there’s little or no disturbance from passing boats. When the weather’s good, it’s a lovely suntrap, surrounded by salt marshes and rich with wildlife. We spent a good couple of hours at anchor here, enjoying lunch on the aft platform while a couple of seals played around us. True, access through the Upper Wych Channel can be shallow, but in a place with so many boats, the relative remoteness is part of what makes this spot so attractive.

Out to sea

The Rotax-powered Sportjet 520 is almost as easy to manoeuvre at low speed as the Sea-Doo personal watercraft that share this engine. In particular, the ability to retain active steerage in neutral is a welcome asset on a jet boat – and yet after a day or so in the short, wind-driven chop of the harbour, we’re keen to see what this high-performance model can do out at sea. And when we get the chance to hit the throttle, the behaviour of the obedient but restrained 520 is immediately transformed …

The hull gets up and flattens off, the ride dries out entirely and the comfort is of a different order altogether. Those aft fins also make their presence felt in a handling profile that errs more on the side of grip and heel than in the traditional jet boat traits of slide and spin. Of course, there is still enough slip on offer to remind you that this is a jet craft, but it’s not like the ‘soap-dish-on-ice’ machines of old, where you could simply pull a 180 at top speed with an armful of lock. Instead, when you put this boat over, the slick, dry, high-running efficiency of a fast plane settles into a very secure heel. The fat tube arrests the dip of the inside edge and you power round with a lovely blend of tenacity and composure. In fact, even without any direct control over trim, the 520 runs unerringly flat and fast, lifting high on the straight, carving hard in the turn and never threatening to allow the naked aggression of its pace or pickup to undermine your helming confidence. Despite being the lightest (580kg) and most powerful (200hp) Williams at this length, it flatters the helmsman, whether you’re cruising at ease or subjecting it to a fistful of frothy heroics at 45 knots.

However, there’s really only room for one man behind that screen – and when you jam your lower back against the backrest, you also have to crane forward to reach the wheel and throttle. After a time, you find yourself abandoning the backrest altogether and shunting forward to perch on the edge of the seat instead – and the same goes for your co-pilot. Certainly, the foot braces, the stability and the surprising softness of ride keep things comfortable, but it would be preferable if the best position didn’t come at the expense of your back support.

In terms of its dynamics, however, this boat cannot be faulted. It is fast, stable, responsive, controlled, aggressive and dry. The fact that Williams only builds jet boats probably has a lot to do with that, but it’s the testimony of my girlfriend that really rubber-stamps my thoughts. After all, despite being five months pregnant, a relative novice in powerboats and habitually nervous of speed at sea, she has more faith and confidence in this craft than any other fast planing boat I have yet shown her. Even in the middle of a 45-knot turn, the Sportjet’s slick efficiency leaves her remarkably unruffled – so, content with that, I change course for the shelter of South Deep to inspect some of the 520’s finer details.

Back at anchor

The 520 uses the same layout as the smaller 460, with a spacious swim platform, a convertible aft sun pad, a starboard helm console and a forward seating section. But the key difference (other than hull length and power) is at the front of the console, where the 520 uses a comfy two-man seat with dry storage underneath. If you fit a mini table in the bow, this then generates a four-man dining space, and that’s an asset the 460 simply doesn’t have the length to replicate.

However, Williams describes both the 460 and 520 as ‘pocket ski boats’, and when you go aft of the console, you can see what they mean. With space for just six people, this Sportjet model might have less seating than comparable craft from the Turbojet and Dieseljet lines, but it also has the ability to hit the plane flatter and faster than its siblings. In addition to extra deck space, it also has some useful aft-facing positions for spotting a skier, plus a very secure and well-appointed swim platform with multiple grab handles. Factor in the ladder and ski pole as part of the standard package and it is plain that this boat is optimised for active family sports ahead of mere people-moving duties.

Of course, given the fact that it’s nearly 300kg lighter than the smaller Dieseljet 505, it could certainly still be used as a tender, but with 90hp more power, 10 knots extra at the top end and greater room to move about on board, it offers a more versatile palate than that of a simple taxi. These qualities also make it easy to store and tow – and if you do decide to run it up a beach, it should prove just that bit easier to manhandle.

In terms of features, both the provision and quality are commensurate with the work of a builder accustomed to high-end demands. For instance, the platform and cockpit sole are lined with tight, spongy SeaDek matting, which is a genuine pleasure to walk on, particularly when barefoot. There are also lots of grab handles, not just in the form of rigid steel rails and tube-top D-rings, but also in the shape of flexible straps fixed to the seat bases ahead of the helm. These allow you to sit up front at pace and feel properly anchored to your seat. Of course, exposure to the wind and the impacts makes the bow seat on any open boat feel a touch dicey at 40 knots, but it’s an excellent idea and one all too rarely seen on compact RIBs.

Elsewhere, I like the fact that the cushions are hinged and relatively low-profile, enabling them to swing up in tandem with the lids whenever you want to access the storage boxes. I also like the fact that the impressively dry storage spaces come equipped with practical and attractive net liners. However, some of the spaces could do with gas rams to free up both hands when shifting gear around. They could also do with drainage holes to avoid the need to sponge them out after a trip. And back at the transom, the absence of an A-frame or any elevated mouldings means you have to tie off on the tube-top rail. It certainly looks well enough built to handle it but I would always prefer a proper cleat. 


Poole Harbour is by no means an unqualified Utopia. Despite some attractive anchorages and mooring spots, plus sufficient variety in land mass to offer shelter pretty much irrespective of conditions, a culture of private ownership means getting your boat ashore can be a trial. That’s fine if you want to retain your solitude by staying afloat, but if you fancy a walk or a beach picnic on any of the islands, you generally have to get a ferry, rent a cottage, wade ashore or trespass. Of course, there are very few harbours in the world better equipped for tourists, but if you’re on your own boat and you want to enjoy the beach, you might be better off heading out to Studland Bay.

Our craft for this brief cruise, however, is everything I had hoped. As the fastest and most entertaining driver’s boat in the fleet, it does of course feel criminally hamstrung by the dictates of Poole’s speed-restricted shallows – but at pace on open waters, its dynamic manners are every bit as impeccable as the reputation Williams have taken such great pains to build. For its water sports potential, helming acumen and unadulterated grunt, this stand-alone boat has to be considered a very effective tangent indeed.

Poole Harbour charts

  • Admiralty: 2611
  • Imray: Y23

Further information

Sportjet 520 specifications

  • LOA: 5.2m
  • Beam: 2.02m
  • Dry weight: 595kg
  • Tube fabric: Hypalon
  • Seating: 6
  • Fuel: 100 litres
  • Engine: Rotax 4-TEC 200 jet propulsion system
  • Max speed: 45 knots

Notable standard features

  • Ski pole
  • Bathing ladder
  • Swim platform
  • SeaDek lining
  • Steel handrails
  • Four lifting points
  • Convertible sun pad
  • Three-year warranty

Notable extras

  • Garmin 451 chartplotter
  • Fusion music system
  • Bimini

Price: £39,995

Contact: www.williamsjettenders.com

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