America’s Cup Roots.
Before that final shootout takes place however, a two-year regatta series is underway using reduced-size AC-45 boats.
OK, I use the term “boat” here somewhat advisedly; I’m not talking about the dinghy your mom sails to church on Sunday. The AC-45 is different; it’s a super-speed-extreme, water-based, wind-powered platform. It’s more like something CERN would sail to near lightspeed in the Large Hadron Collider, and then smash to study the quarks emitted.
Take a look:
Ok, I admit that video uses edited clips to make a point. I also agree there is huge excitement, history, and spectacle associated with the Americas Cup series. This is the absolute ultimate contest of no-holds-barred sail power.
Here’s a full clip from San Francisco’s recent AC45 World Series; it’s a bit more nuanced, but just as much fun:
The global significance of the AC regatta and the mythic stature of the AC yacht designs raise a high challenge to virtual boat builders. Not many have the skill, street-cred, and frank audacity to bring this kind of boat to Second Life. Luckily, Corry Kamachi and Wildwind are at the top of the list that do!
In February 2011 Corry released an early prototype, called the ACJ-35 Wildcat. The boat was fun to sail and a good club racer, but it handled more like a Wildwind monohull and lacked the pizzazz a sailor would want from a Cup contender. Corry was aware of this, and described the ACJ-35 as a “simple, small” boat that was “race convenient.” Meanwhile, she worked on the more ambitious “45.”
Well sportsfans, that new Wildcat45 just hit the water, and its pretty fantastic. It’s the big catamaran many SL racers were wishing for this past year, and frankly it’s a good deal more. Let me fill you in on just a few of the details.
The physical design and dimensions of the Wildcat45 very closely match the real-life AC 45 Rule. Go look at the America’s Cup blueprints, then grab a tape measure and walk around the Wildcat45 in Second Life; it’s impressive. The craft work and care that went into this realistic build is evident, from the towering sail rig down to the tiny details.
What you get
When you open the Wildcat 45 v1.0 box, you’ll actually find two versions of the boat included. They superficially look the same, but one is mesh and the other is sculpted. Although there are major advantages to mesh construction in SL, most sailors know that Second Life is having difficulty updating the grid servers to support mesh vehicles. Wildcat45 acknowledges this problem, and gives you the best of both worlds.
The box also includes detailed notecards about the boat’s operation as well as instructions about adjusting settings and textures to fit a sailor’s personal preferences. The options are full-featured; you can set the com channel, the operation mode, the sheet-step size, and adjust the sit and cam positions.
If you want to change the boat’s textures, there are several subfolders that include templates for the hull, sails, and rigging. There are also specific UV maps and sculpti textures that should give experienced sailors everything they need to pimp their ride.
Physical and Phantom
Most of my comments apply to the mesh construction version; I’m guessing in a month or so that will be the version sailors prefer. A few days ago I commented about a new realism that’s emerging in SL sailcraft, partly due to mesh construction. SL vessels are evolving an ever-closer match to their real-life counterparts, and the Wildcat45 is a great example of this trend, in both appearance and performance.
The boat has two symmetrical hulls , with all the hardware and rigging you would expect from the real boat. Collision tests with Wildwind45 show that “the boat you see is the boat that bangs into things” (that’s good). However, the mast and sails are phantom while underway, as are both rudders.
This is a catamaran, so there’s no keel, but the boat has daggerboards in each hull that automatically deploy to offset heel effects. The boards are not phantom and will stop the boat if they hit something. However, since the board only deploys on an actively moving boat, when the underwater section of a daggerboard hits an object it will automatically raise. That feature lets a skipper make a quick recovery. 🙂
Wildcat45 does not have a mainsail; it has a hard wing instead that functions like an airplane wing. On the leach end of the wing (the trailing edge) there’s also a large adjustable panel that works to adjust lift (more on that below).
In addition, the boat comes with two headsails: a normal, working jib and a much larger gennaker that provides an extra boost sailing downwind.
Wildcat45 also comes with a redesigned Wildwind Control HUD with a dual column of buttons that control many standard sailing functions. However, a skipper can optionally do away with the HUD and sail the boat just with chat commands.
The boat comes with two additional “Info HUDs” that provide very detailed feedback about boat speed, sail status, and wind parameters. One of the Info HUDs is for a crew member, since the Wildcat45 crew can actively switch sides on this boat to adjust heel angle and maximize speed.
The boat also has a detailed numerical HUD readout typical of earlier Wildwind boats, so in high lag situations the sailing team can actually do without any of the new HUDs I just mentioned. As I said earlier, this boat has lots of options. 🙂
If you’re familiar with sailing Wildwind boats, and particularly if you know the ACJ-35 or ACJ-90, you’re in for a big surprise. A lot has changed in the Wildwind design to make the engine and features of the boat more realistic and sheer fun to sail.
First of all, Wildwind has switched to use map compass headings instead of the old draftboard compass system that was a Tako legacy. That makes life a lot more convenient!
Wildcat45 has built-in boat wind, and a skipper can set the numerical wind direction and speed using chat commands. The boat has a separate racing mode that picks up cruise wind settings from a race line WWC. You can easily tell which boats are sailing in race mode since they automatically display the user-set race numbers at the top of the wing.
The biggest and best change in the Wildwind engine is the use of full-strength apparent wind effects! Nearly all earlier Wildwind boats used a ‘weighted’ headwind adjustment that was about one-third the real life Apparent Wind correction. Although there were good arguments in favor of this adjustment, the use of a proprietary wind algorithm made it difficult to race the boats in a mixed fleet, and it made the boats less realistic.
Well sports fans, that’s all history. 🙂 The Wildwind engine now uses the standard real-life calculations to turn real wind parameters into the apparent wind forces that drive the boat. That’s a very nice thing!
Sailing the Wildwind45
Let’s talk sailing! When a skipper raises sail on a catamaran, one of the first and most important goals is to get the windward hull out of the water. Riding on one hull cuts the drag effects in half, and the boat starts to fly.
Both the Info HUD and the simple numerical HUD report heel angle, and Wildwind45 is designed to generate a maximum boat speed with a heel angle of 35°. Be careful, though; if you’re caught by a gust, the boat capsizes at 45°, and you’ll be left hanging on for dear life (see below). 🙂
You might think this is only a problem sailing upwind or on a reach, when heel effects are maximum. Well, you’d be wrong. 🙂 Ask Russell Coutts!
Wildcat45 has the same propensity to pitchpole as the AC-45. If you’re flying with the wind behind you and the Genn up, the pitch effects increase. If your nose catches a wave and you suddenly pitch forward over 15°, there’s no looking back. You’ll go flying over the handlebars! 🙂
Since heel is so important to boat speed, the Wildcat45 has a few ways for a sail team to adjust the angle. Both the skipper and crew can hike to either windward or lee positions to get the boat flying at optimal heel, and under high wind conditions it may be necessary to spill wind to keep from flipping over.
Wildcat45 has another tool, however; it’s a wing extension that’s adjustable and acts just like the flap on an airplane wing. Take a look at the images below, and you’ll see what I mean. The picture on the left shows the boat sailing with heel= 29° using a minimal flap effect (Flap 1 setting). On the right, you can see that the flap has now visibly turned up (Flap 3 setting). That change increases the aerodynamic lift, and the heel angle goes to an optimal 35°, with a corresponding 10% speed boost. 🙂
I’d suggest getting some practice with those flaps before hitting the racecourse, though; they can be pretty treacherous. (Ask Coutts about it. 🙂 )
The chart to the right should give you a rough idea of what to expect sailing this boat. It shows boat speed plotted against real wind angle with a constant breeze of 9.7 kn. Sailing with the jib at an upwind heading of RWA 50, the boat already exceeds real wind speed. As the boat falls away from the wind, it quickly maxes out at roughly 120-125% RWS, until the boat falls gets to a heading of RWA 110.
Beyond that point the jib becomes progressively less efficient, so it’s a good time to raise the gennaker. From RWA 120°-140° the gennaker will give an extra speed boost to a maximum of 125-130% RWS. By RWA 150°, the sails are no longer providing significant lift and the boat is primarily driven by drag effects.
This boat wants to fly, not be pushed, so drag effects are pretty inefficient. There is a realistic, rapid decline in performance over RWA 150° to a boat speed that’s roughly 60% RWS.
The second chart above shows the same data, with a new curve added in green to show the boat’s performance with twice the wind strength (RWS 19.4 kn). At these wind intensities, the boat speed seems directly related to RWS; if you double the wind speed, the boat goes twice as fast. 🙂
The combination of beautiful design, accuracy of detail, and blistering speed are all trademarks of Wildwind boats. It’s frankly a thrill to sail a new one again. I can say that with even more excitement, given the wealth of features offered by Wildcat45 and the dedication it took to bring this version of the AC-45 into Second Life. I think this is easily the best sailing vessel ever released by Wildwind, and given the large number of very popular boats skillfully crafted by Corry over the years, that’s saying a lot. 🙂