Advantage Virtual Racing 2011

Advantage is a full-featured professional-level program developed and improved over the past 15 years for local and open ocean yacht racing. The Advantage Virtual Racing Edition has been modified to intepret wind data and apply it to calculate and predict boat position in exactly the same way as it is done in the most popular online virtual race games, including the Virtual Regatta (VR) races, the Virtual Loup-de-Mer (VLM) races and the new Volvo 2011 race. Advantage is the only weather-routing software to provide a virtual race mode for accurate virtual race calculations. There is simply no comparison between Advantage and the various "free tools" developed to assist virtual race competitors. Some of the more important Advantage features are discussed and illustrated below.

Weather routing uses wind predictions and boat polar performance files to predict where a boat will be at given time for a possible course. Routing programs consider all possible routes to determine the quickest, something no one, not even the best real-world navigators, can do in their head. Because wind is held fixed for 12 hours in both the new Volvo 2011 and Virtual Regatta games, a routing program can determine the quickest route in a given 12-hour wind period with little to no uncertainty. This is because the program uses the same wind data as the game and the only source of error is the boat's polar file, something that can either be downloaded for Virtual Regatta games or developed, over a matter of days, from observing values in the Volvo game. The program therefore takes all guesswork out of short-range tactical decisions.

Over longer periods, a routing program can look a week or more ahead (as much as 16 days with the MRF forecast) and help you develop a strategic plan that maximizes speed overall. Often a route that moves the boat optimally forward in the first couple of days is not the best choice when you consider the conditions the boat will experience a week later. Again, this is very difficult to do in your head, which is why all of the professional real-race navigators use Advantage or a competitor routing program. While each navigator has his preference, none of the other routing programs is useful in virtual race routing because the games artificially hold wind fixed for 12 hours, unlike the real world. In contrast, Advantage offers the option of virtual racing modes which exactly reproduce the way the games compute wind from freely available GFS forecasts. In addition, Advantage’s routing method and related functions are unique in the industry.

ROUTING EXAMPLE: the image below is a routing solution during the first leg of the Volvo 2011 Race, now underway. The router identifies an optimal red route, and 5 comparison routes to the next Volvo Gate. The times for each are shown in the Best Course Comparisons box, along with the distance to the mark. The optimal red route is some 20 hours faster than the green route, and about 5 hours faster than the magenta route. The black dots show the predicted position of the boat on each of the routes at 13:35 on 11/14. You can change the display time to an intermediate time of your choice, or use the arrow keys to step along at equal time intervals.

Advantage's unique weather routing method identifies not only the “optimal” (quickest) route, but 5 alternative comparison routes, each with time to transit and the minimum and maximum wind speed predicted on the route. Sometimes the optimal route is only slightly faster, and there may be other reasons to prefer a different route. For example, a marginally quicker route may pass close to a shoreline or obstacle, requiring more hands-on time to avoid running aground. Or, you may prefer to stay closer to certain competitors, rather than risking a wide separation that may not pay off. You can simultaneously "step" along the optimal and alternative routes to compare positions and distances to the destination at any time. Knowing the minimum wind on a route is an important clue as to its likely accuracy. Light winds are very difficult to predict reliably even a day in advance, so it is often safer to choose a route that is predicted to take somewhat longer but which avoids "holes" in the wind.

With Advantage you can route either from present boat position or from a defined mark, and you can define a mark with a variety of methods: visually, by clicking on the chart, or dragging a mark to a new location, by typing in coordinates, or defining by range and bearing from boat position or another mark. Once the optimal route is computed and displayed onscreen, you can follow it visually, adjusting boat heading in the game as required, or (better) choose to save it as an Advantage “Course.” As with any Course, you can then "Solve” the Course (compute time to complete each leg, including ETA, time to sail, heading, boat speed, wind speed, TWA and other data for the leg; as well as overall time and ETA), starting either from the first mark or (if you later load the Course), from boat position to the next unsailed leg, and continuing with the remainder of the Course. Course Solutions are automatically saved to a daily file, and can be printed at your option.

In addition to routing solutions, you can define a Course by a variety of methods, such as a “Quick Course” by point and click, or a Great Circle course. With most virtual races, you can use the results of the Course “Solution” to program a series of changes in heading or TWA at specified times or waypoints that will reproduce the Course without the need for constant hands-on online attention (in other words, you get to sleep).

OPTIMAL COURSE EXAMPLE: the result of Course Solve is shown below, breaking down the Course into a series of legs and showing the wind speed (TWA or TRG) and true wind angle (TWA) on that leg, boat speed (SPD) and heading, the time to complete the leg and the ETA at the next waypoint. The notation TRG signals you that this leg is either upwind or downwind, meaning that you cannot sail the indicated heading directly, but must tack back and forth along the indicated heading. For these legs the TWA shown is the optimal tacking angle for that wind speed, whereas for reaching legs (TWS shown), the TWA shown is the TWA achieved on the indicated heading. Advantage has special tools for breaking down upwind and downwind legs into specific tack sequences. This Course has many legs, and you need to scroll down with the slider to see the rest. At the bottom, the display gives the overall time, distance and ETA for the Course to arrive at the destination. What you see in the summary is automatically written to a daily file, and you can use the other buttons to see the coordinates of the intermediate points (List Marks) or print this Solution directly to a named file of your choice.

Advantage has unique functions for upwind and downwind sailing. In addition to calculating and displaying static laylines (based on instantaneous wind values at a point), Advantage computes and displays dynamic laylines, which take into account the variations in wind speed and direction that occur while the boat is sailing to the mark. This provides a much more accurate portrayal of upwind and downwind legs over a period of hours. The quickest way to reach an upwind or downwind mark is to sail at the boat’s optimal tacking angle (optimum TWA), included in the boat’s polar file. Advantage’s unique “Super-If” function computes an optimal series of tacks to a mark assuming the boat is always sailed at its optimal tacking angle. You can compare a two-tack solution (on port tack to the starboard layline vs. starboard tack to the port layline), or a more complex series of any number of short tacks. With this function you look forward to tacking situations where you can always gain on your competitors.

DOWNWIND SAILING "SUPER-IF: EXAMPLE: the image below shows a downwind approach to a temporary mark labelled "99." The static laylines at the mark (instantaneous wind) are shown as the solid blue lines, whereas the magenta dots show the dynamic laylines taking into account wind changes during the tacks (these are curved lines, in general). If sailed at its optimal tacking angle (something to be adjusted along the tack if wind strength varies significantly), the boat will follow the curved lines shown (the red line if on port tack, or the green line if on starboard tack). When the boat reaches the corresponding layline, it tacks to follow the path shown by the magenta dots to the mark. In this case the Super-If calculation shows that the port tack sequence is some 39 minutes faster. This calculation compares 2-tack solutions, but you can increase the number of tacks to see if the time can be reduced further.

This display utilizes the alternative "Bare Chart" display, which is useful for short distance tactical computations in open water (it does not show shorelines or obstacles), but you can do the calculation over any chart. The dashed lines in the Bare Chart display break it down into squares 1 degree on a side, centered at an integral lat-lon point. This is useful for VR games, where the wind is held constant within such squares and changes abruptly at the borders.