A foiling Bladerunner catamaran is latest tool in Kiwi weather forecasting PredictWind’s impressive toolbox.
When foiling Waszp sailor Jon Bilger needed a fast, stable vessel for his internationally-renowned weather forecasting service, PredictWind, it was probably no surprise that he opted for a high-tech foiling catamaran from Auckland’s Bladerunner Boats.
PredictWind (the boat) is an 8.5m aluminium hardtop catamaran, widened to 3.1m and fitted with a solid foil, positioned in the middle of its tunnel. Designed to vastly improve efficiency, the foil effectively “carries” about 90% of the boat’s weight and has been shown to reduce fuel consumption by around 40%. When you have a 4200-kgs boat able to travel at speeds of up to 50 knots — and with fuel consumption as low as 1.8L/NM — that is savings on an extremely worthwhile scale.
Powering Predict Wind is a pair of Evinrude E-Tec 250hp outboards. These have been fitted with air intake hoses, colloquially known as “snorkels”, designed to funnel fresh, dry and clean air, hopefully almost entirely salt free, from low down in the cockpit, under the transom.
According to the company’s business development manager, Nick Olson, the very technical nature of both the catamaran’s foiling design and the E-Tec outboards are an appropriate fit for PredictWind, which is, after all, primarily a tech company.
PredictWind are mainly using their new Bladerunner to collect and verify weather data, service their observation points around the Hauraki Gulf and for promotional activities. This latter includes transporting, launching and retrieving the two foiling Waszps that Jon and Nick race competitively — which explains the large blue crane that graces the starboard side of the cockpit.
To assist in the data collection and the transmission of that data, the boat is fitted with B&G MFD running its version of the PredictWind program, a Raymarine Axiom MFD on which a beta Android version is being tested, an iPad connected to the PredictWind website, a 4G LTE antenna on the hardtop roof and a satellite connection.
On the foil
Although most people think of foiling boats in terms of zippy sailing dinghies (like the Waszps and Moths) or the new generation of America’s Cup yachts, Bladerunner’s Greg Shine has been designing and building foiling catamarans for the best part of 30 years. The PredictWind 8.5m version is the 96th Bladerunner catamaran to hit the water since the late 1980s and several more are in the design or construction stages.
An early adopter of the CADCAM system, Greg has long modelled his vessels in 3D before putting them through hydrostatic and other similar programs. Every part of the vessel is then sent to be computer cut meaning even quite intricate custom designs can be assembled relatively quickly, efficiently and cost-effectively.
The designs feature twin deep vee hulls with a fixed foil positioned in the tunnel at the centre of lift (on PredictWind it is about 3.5m forward of the transom). The foil is constructed from aluminium, just like the boat, is supported by a central strut and is an integral part of the structure.
Greg explains that, although the positioning of the foil is vital (and takes a lot of very detailed calculations), once that’s done the boat is almost completely unaffected, in terms of speed or fuel efficiency, by the addition or even placement of more load.
As the foil’s angle of attack is dependant upon the trim of the boat, the foil is automatically positioned to present its best and most comfortable profile, regardless of whether one is belting into a hard on-the-nose sea (when it keeps the bow down) or sweeping quickly down a following one (when the boat is almost out of the water, with the twin keels providing track-like control).
Greg says the way the foil works, the boat can go through the entire speed range (including traversing the hump) without any adjustment to the engines’ trim.
This allows the trim to be used to counter the sea state as normal, but with much greater efficiency.
“Because the foil is the trim pivot point, there is a wide range of trim available for different sea conditions,” explains Greg.
“In a choppy head sea you put the bow down and the hulls carve through the water with great speed and comfort; the long, deep vee hulls bridging the chop and the foil slicing straight through the waves to give an extremely soft ride.
“In a large following sea, it is possible to lift the bow high, creating huge reserve buoyancy; at the same time, the symmetrical hulls track the boat with no tendency to broach, even in extreme seas.”
The design also allows the boat to retain a very low on the plane speed.
Sadly, with Auckland’s spring weather reverting to depth-of-winter grisliness, the only suitable day to get on board and get some photos was also a low wind one. Nevertheless, it was pretty obvious that the Bladerunner was performing as desired, giving a very soft ride in all directions and turning tightly with no outward lean or discernable vices.
Practical layout
PredictWind was founded by 1992 Barcelona 470 Olympian, current world foiling Waszps Masters Champion and renowned America’s Cup weatherman, Jon Bilger.
Having had access to what was, at the time, some of the best weather modelling available, he thought how wonderful it would be if that same technology and level of detail was able to be accessed by the world’s sailors, power boaters, ocean-crosses and fishers.
Obtaining an exclusive right to some of the most advanced weather modelling technology then available, Jon and his development team also secured the necessary topographical information to offer incredibly specific and detailed weather forecasting at some 20,000 locations around the world.
“The technology is the culmination of 30 years of experience by a team of research scientists,” says Jon. “It is cutting edge technology that had not previously been available to the public prior to the release of PredictWind.”
Although headquartered in the unassuming Auckland, New Zealand suburb of Te Atatu, PredictWind’s biggest market is in the United States, followed by New Zealand, Australia and Europe. The company also has offices in the US, the UK and Australia.
Like many tech companies, PredictWind offers both a free service and a more detailed, paid subscription one. Perhaps unusually for such companies, however, around 50% of their users subscribe to one of their three paid services. All can accessed anywhere in the world through their website or their iOS and Android apps and offer detailed local weather information.
The free service offers a daily weather briefing, a variety of different modelling tables and graphs and, perhaps most importantly, accurate local wind maps.
The subscription services start with the $US29pa Basic. It has everything in the free service as well as Wave, CAPE (Convective Available Potential Energy), Gust, Rain, Cloud and Isobar maps, along with more detailed wind mapping.
The $US249 Standard service, often the option of choice among offshore sailors and cruisers, also features detailed Route Mapping and Departure Planning, Sea Temperature maps and both satellite and SSB email delivery.
The top-of-the-line Professional service, $US499pa, offers even better resolution, sea and ocean current charts, showing where the stronger currents are, and a number of other advantages for those who spend their professional lives crossing the planet’s oceans.
Both the Standard and Professional services are also available over a satellite connection.
At the time of going to print, the company was currently spending quite a lot of its development time on a new PredictFish service, although details of exactly what this will contain and when it will be launched are understandably commercially sensitive.
Like much modern technology, PredictWind might be incredibly complicated and hard to understand at a “how it works” level but is exactly the opposite at the far more important “how it is used” one.
To illustrate this, Nick demonstrates how to pull up the “shadowing” program on the bulkhead-mounted iPad. Picking a nearby headland, the program shows the headland’s effect on the wind, clearly illustrating (by the use of different shades of colour) exactly where it is casting its wind shadow. While all of us who have sailed, boated or fished close in know about “the lee of the land”, many might be surprised by just how far from the shore this can actually stretch.
As someone who prefers fishing close to the land and preferably with no wind or at least the wind and the current going in the same direction, such a feature would be invaluable, especially when combined with a tide or current map.
With his racing and business background, Jon is obviously excited about the upcoming America’s Cup in Auckland and the opportunities it presents. Although nothing has been finalised as yet, he is hopeful that, through Emirates Team New Zealand, the event authority and possibly the host broadcaster, PredictWind will end up front and centre of weather forecasting and modelling for the pinnacle event.
Specifications
- Model & Model: Bladerunner 8500 HT
- Designer: Greg Shine
- Price as tested: $NZ385,000
- Priced from: $NZ300,000
- Type: Hydrofoil Supported Power Cat
- Construction: Aluminium
- LOA: 9.9m
- Beam: 3.1m
Weight: 4200kg
Test Power: 2 x 250 Evinrude ETEC G2
Propeller: Rebel 18”
Power options: Outboard or Sterndrive
HP Range: 2 x 135hp-250 hp
Fuel Capacity: 800 Litres
Manufacturer: Bladerunner Boats Ltd | Ph 09 412 8096 | bladerunner@xtra.co.nz | www.bladerunnerboats.co.nz
| RPM | Knots | L/h | L/NM | Range (NM) |
| 3100 | 20 | 41.8 | 2.1 | 340 |
| 3500 | 27 | 53 | 2 | 360 |
| 4100 | 32.7 | 73 | 2.3 | 310 |
| 4500 | 36 | 88 | 2.5 | 280 |
| 5000 | 40.5 | 108 | 2.7 | 260 |
| 5300 | 42.8 | 124 | 2.9 | 240 |
