Performance Options. Performance Options

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1 Performance Options Performance Options ROUTING OPTION The Routing option is born of MaxSea s long association with short-handed racers. It combines the data contained in long-term weather (GRIB) files, and information which you input about the performance of your boat, and then selects the best route for you to sail based on this information. More than 80 percent of all short-handed racers, Volvo/ Whitbread racers, and other high-end racing programs use a form of this software to choose their fastest route. Often, they are using it when they are tired, and not thinking clearly conditions which demand that the powerful features of Routing be intuitive and easy to use. Of course, when we are cruising, the trade-offs are different. What we are after is the safest, most comfortable, and then fastest route. Sometimes these are the same, other times they are not, and routing helps you make the right choice for your needs. To get the most from this feature, SetSail-MaxSea helps you create a series of performance polars (as previously mentioned, polars indicate how fast the boat sails at different wind angles and in different wind strengths) for your boat or you can use one of the SetSail-MaxSea standard polars. You might include the use of your engine in certain conditions in one of the polars. In another, you might slow down the upwind performance significantly, so the routing algorithm looks for a course which is more off the wind and thus more comfortable. How does this work in the real world? Suppose you are sitting in Bermuda in mid-may trying to pick the right time to head back to the Eastern Seaboard. With continental cold fronts sweeping into the Atlantic every few days, and the Gulf Stream to cross, choosing the right time to leave is critical. With Routing you can download a new GRIB file each morning, and then let SetSail-MaxSea plot the fastest course to your destination. You can check the wind direction and speed, boat speed, and position for every two hours during the passage. You can also see how much better progress you would make if you motorsailed in light airs. After you ve checked departing on the first day, ask SetSail-MaxSea to start the passage on the following day, and compare the wind direction, speed, and other data (one of the things you will want to make sure is that you do not meet any cold fronts while you are in the Gulf Stream). While Routing cannot make all the decisions for you, and is only as good as the GRIB file on which it calculates, it allows you to see many more possibilities for a safer, more comfortable passage than might otherwise be the case. Avoiding Bad Weather When you look at the route list generated by the Routing option, you see true and apparent wind speeds and direction, as well as boat speed and position, at regular intervals. This is a much better way to get a feel for the conditions that are predicted than just perusing a weather fax chart. This is especially true with the read-out of apparent wind strengths and directions. Becoming a Better Cruising Tactician Short of accumulating thousands of sea miles of real-world experience, learning how to play the weather for best advantage is a very difficult process one in which most of the important lessons need to be learned the hard way. But now, with the SetSail-MaxSea Routing option you can gain valuable experience at home. We know this sounds too good to be true, but consider the previous example going from Bermuda to the East Coast. You 143

2 could just as easily play the same what if games from your office in Des Moines, Iowa as you can anchored in St. Georges Harbor in Bermuda. Routing gives you the ability to learn the best way to use weather to your advantage without getting wet or bounced around. You can evaluate how changing course this way or that to avoid bad weather works out, and check where you would be relative to the weather at different times during test passages. And you can do this for any of the cruising areas in the world. Want to double Cape Horn, or sail from Hawaii to Kodiak, Alaska? How about making the trip across the Indian Ocean from Bali to Cocos Keeling Island? As the seasons change, pick the best time to test a passage anywhere around the world. Is This the Right Boat? Evaluating the right boat for a given cruising scenario is filled with misinformation and pitfalls. The bottom line is that until you ve made some passages, in a variety of weather, you will never know if the performance trade-offs are right for what you want to do. But with Routing you have a method of making what in essence are real-world comparisons between different boats. You can use different performance polars to see how fast one boat might make a passage in a given weather pattern and then compare it to another design you might be considering. The fact that you can do this in the weather conditions from anywhere in the world makes this Routing option all the more valuable. It is our feeling that a judicious use of Routing can go a long way towards helping you decide what is the best boat for your plans and budget. Stuck on land and still thinking about the right boat? You can choose from the performance polars for many production boats. And if you want a real buzz, take advantage of the database of performance polars for some incredible racing boats like the Maxi Cats from The Race, Open 60 monohulls, and the Open 60 trimarans and try your hand at weather routing, using these wonderful machines as your ride. Which Performance Data? Before you launch Routing you need to choose a polar file. You may have already done this when you first started the program. You can use any file which is in the.pol format. As we mentioned earlier, for real-world cruising and racing it is usually best to have two or three versions of your polar files, and choose the one (or run different ones) which best fits the conditions. Aboard Beowulf we have a pure sailing, smooth water polar. Then we have a second which is more realistic with sailing speeds reduced ten to 20 percent for waves and the fact we are not paying close attention to trim, with some motorsailing thrown in for lighter airs. Our third polar includes aggressive motorsailing allowances (if the speed drops below 10 knots when beating or running, on comes the diesel). Selecting a Weather File The next step is to select a weather file. If you ve downloaded a file from the Set- Sail.com web site it will open automatically. Or, if you are using historic data (SetSail s or your own), double-left-click on the file you want to open and it will appear on the SetSail- MaxSea desktop. If you already have loaded a weather file, and turned it off, left-click on the weather icon at the bottom of the page to bring up the weather data on the computer screen. Performance Options To run a Routing: Choose a polar file (if one is not already chosen). Open a weather file or turn on one which is already opened). Add a destination waypoint. Select Route Plan from the Racing menu. Routing automatically calculates fastest course. To stop a Routing which is underway: Left-click with the mouse. Select Stop or Continue from the window that appears. Note: Starting with SetSail-MaxSea edition 9.2 there is no longer a time limit on routings. You can make them as long as the course you have to sail and/or the weather file available. 144

3 Performance Options Add Destination Waypoint Next, you need to add a destination waypoint some distance away from your boat s position. If you want to check out a route starting from a point different than where the boat is presently located, turn on dead reckoning. (Go to Navigation, then Dead Reckoning and then give a position for the boat or center it in your chart area. Use the Moving tool to position the boat more precisely.) Here s a passage set up from Bermuda, where the boat is located, to the entrance of the Chesapeake Bay off Norfolk, Virginia. Starting Routing To start the routing process, go to Racing on the menu bar, and then select (leftclick) Route Plan. How Routing Works When you start the routing process, the computer looks at the boat s performance data, and then compares this to the wind information contained in the GRIB file. It computes the position the boat can reach in each time frame, based on the best speed which the boat is able to achieve. This information is represented by a series of lines called isochrones. Each isochrone shows you how far the boat would be able to travel by a given time. You can then decide which is the best route to take to get you where you want to go. All sorts of tactical information is available on this display. We ll discuss some of this later; right now, let s stick with the simple stuff. There are four types of basic information contained on this routing plan. The yellow and purple radiating bands represent the potential position which the boat can reach at two-hour and 24-hour intervals. The faster your speed, the further apart the bands, and vice-versa. Note that the time bands are numbered to make them easier to identify. The black lines are the isochrones, and where they cross the time bands (yellow or purple) is a potential position. The solid red line, more or less following the course between Bermuda and Norfolk, is the course which SetSail-MaxSea is suggesting you sail. 145

4 Performance Options Turning Isochrone Lines On and Off Once the basic routing has been done, we often turn off the isochrone lines. This is done in Racing on the menu bar. Select (left-click) on Display Isochrones to turn them off (do it again to turn them back on). This leaves you with just the suggested course, and the two-hourly plotted positions, as shown below. To turn isochrones on or off: Go to Racing on the menu bar. Select (left-click) Display Isochrones. If isochrones are on this will turn them off, and vice-versa. Projected Data Using the finger tool you can select (left-click) on any of the position markers to bring up the data which applied to that position (boat speed, wind conditions, lat and lon). Keep in mind that you can type any data needed into the open information box on the right side of this dialog box. For example, you might indicate expect wind shift around this point. Watch barometer Route List The route list contains the position, speed, and wind data for every position that Routing has established on the chart. We find this the best way to get a feel for the trip, the wind angles and wind speeds involved, the comfort factors, and risks which may be involved. To access the route list, go to Racing on the menu bar, then select (left-click) on Route List. The dialog box seen below appears. The route list contains all sorts of helpful data. In the upper right hand corner you will find your present position, ETA, and distance to go. In the data fields below you have date and time, position along the route, course and speed, true wind speed and direction, and then which tack the boat is on and the wind angle relative to the boat. Note that the data is presented at two-hour intervals. 146

5 Converting the Route to a Course (Series of Waypoints) Conversion of the route to a series of waypoints is as easy as picking the arrow tool from the tools palette, double-left-clicking on one of the route points to select the route, then using the waypoint tool from the tools palette to select one of the highlighted route points. The route then converts to a series of waypoints. Or, you may just want to follow the red course line. One thing to keep in mind on longer passages is that you will probably be modifying the optimum route with each weather update. Mining the Data There s a motherlode of tactical information hidden in these graphical routing presentations. The key is knowing how to make use of the data which is right in front of you on the computer screen. If you know the tricks of doing this, it can make a huge difference in your passage time, comfort and safety. Getting at this information takes practice. Following is one brief presentation of some of the details from the example we ve been using. If you check into SetSail.com periodically you will find other examples on display, covering interesting situations around the world. You are invited to practice this art, to learn along with us. We promise, it will be a great ride! Let s go back now and look at a couple of interesting features on this routing. The first is to be found at the top of the screen. Notice how close together the time lines (yellow and purple) have gotten. This is the position the boat would be reaching at two-hour intervals, so you can bet that all along this region of tightened lines the winds have become light and/or from an unfavorable direction. Message: Stay away from this area unless you want to use the engine. Performance Options Converting a route to a series of waypoints: Use finger tool to select a point along the route. Select waypoint tool and left-click on one of the highlighted route points. The red route line which is established during the routing calculations only goes away when you run a new routing, or when you close SetSail-Max- Sea. On longer passages and/or in light airs, it may not be possible to reach the waypoint you ve established before the weather forecast runs out of time. When this occurs, SetSail-MaxSea will get you as close to the waypoint as possible. You will then need to update your routing forecasts as new data becomes available. Note that at the end of the routing, the route list gives the time to the last isochrone. Your actual elapsed time may be less. To get an exact time, you need to do a simple interpolation, which is easily done by zooming in and approximating the distance between isochrones. 147

6 Now let s look at the bottom left hand corner. Notice the V shape lying on its side, with the time lines and isochrones all bunched up? This is another area of light winds. Given the normal weather patterns in this part of the world, you can assume that it is caused by a high-pressure system pushing in from the west. If you would like a break from the wind, head towards this area. But if you are sailing, the thing to do is to make sure you get past it before it traps you. It may even pay to deviate from the optimum course a hair to the north to buy some insurance. You will also want to be watching closely what the weather around you is doing as compared to the forecasts. If it appears the weather is a little ahead of schedule, you might want to detour sooner towards the north. On the other hand, if the conditions observed on the boat validate the forecast, or indicate the weather might be late, you can sail the plotted course with more confidence. Like we said on the previous page, if you know how, there s a huge amount of data to be teased out of what SetSail-MaxSea draws when you enable Routing. Movies! This entire routing process offers a lot of material to absorb. You can reach the 60- to 70-percent proficiency level pretty quickly. But to really fine-tune your understanding takes time. The ability to make movies of what we ve been discussing, however, will considerably shorten your learning curve. And on a passage it can be nothing short of wonderful in helping you, and your crew, understand the weather options. The process of making movies is simple, easy to execute, and quick to render, and we cover it in detail in the section on Making Movies/page 121. Right now we want to leave you with the concept of how this works. When you make a movie of the routing, SetSail-MaxSea creates an animation showing how the weather changes at each forecast interval, and how the boat is projected to react to these changes. You actually watch the boat moving across the screen, while the wind arrows change their angle and strength, with the boat changing its course as the routing suggests. Performance Options On occasion when you do a routing you may not like the results. There might be too much wind, or too little, or the destination has too much upwind work. This happens a lot when working with historic weather data and looking at long passages. Now let s come back to what the isochrones represent. Based on the forecast wind and your boat s performance data, you will end up anywhere along the isochrone line. So just find the isochrone which represents the end of time you want to be at sea, and then look for a suitable destination. Try it out it works really well! We find it very helpful to have a printed copy of the routing data to study during the day. Printing this data is easy: Go to Files on the menu bar. Select Print. Select Print from the three choices. You can also save the file as a computer image by selecting Save File. 148

7 Performance Options Here s an example with the boat starting off from northeast of Bermuda. The magenta trail indicates where the boat has been so far on its journey. The series of small images are close-ups of different points during the above movie. Note how the wind data and boat s position relative to the wind changes in each frame. These three images were taken in the middle of the chart shown above, where the wind is swinging around a frontal boundary. There is no better way to learn what Routing has in store for you than to make one of these movies, and then play it half a dozen times, stopping it at positions you wish to study closely. 149

8 Super-Long Routings Starting with SetSail-MaxSea edition 9.2, the time limit on routings has been removed. This means you can run a routing as long as your weather file. Used with the Next Generation Pilot Charts, you can now check very long passages. By now, you are well familiar with how to use routing to compare boats. For this example, we ll dispense with the preliminaries and get right to a passage from Bermuda to the Azores. We ll use two boats from the same period a Columbia 50 and a Peterson 44. These boats have similar interiors in terms of volume. The Columbia 50 can usually be bought for less than the Peterson 44. Which will get you across the pond the quickest? Let s see what happens. Performance Options Super-long routings require a lot of computer power. A routing like the one shown below will take 30 seconds to a minute on a 400MHz machine and a few seconds on a 1 Ghz computer. Longer routings take geometrically longer time frames. If you are practicing at home, turn on dead reckoning (under Navigation on the menu bar). Then select the divider tool in the DR palette, and type in the Lat/Lon of the starting point (or accept the center-of-chart option, and then drag the boat to Bermuda). Next, select the waypoint tool and place a waypoint near Flores, the westernmost of the Azorean islands. We now have to choose a year and month from the Next Generation Pilot Charts. We re using June 1998 here. Double-click on this to open it, and then re-scale the chart to something easy to view (we use 25 million-to-one). Now, go into your Performance File folder and choose a boat in our example, we start with the Columbia 50. Double-left-click on the file you want, and it will be imported into Set- Sail-MaxSea. Finally, go to Performance and select Route Plan to run the routing. You can get a quick idea of the time involved by counting the purple isochrones, which occur every 24- hours (nine days here). 150

9 Performance Options To turn off the isochrones and view the projected course, go back to Performance on the menu bar and click on Display Isochrones. This will turn them off (click on this item again to turn them back on). Now a trade-off in software design: When you are zoomed out, as in the above example, the daily tags often cover up some of the suggested course. The tags are very handy when you are zoomed in, but a pain like this. We had to make a decision one of those trade-offs. So, you get a better look at the data zoomed in closer. The other approach which gets you all the details at each two-hour interval is to go to Performance and then select Route List. Okay let s check out the Peterson 44. Go back to the Polar folder, and double-click on the Peterson 44, and then run the routing again. You will find that the Peterson is about a quarter of a day faster. Not much in the context of an eight-day passage, unless there is a storm bearing down on you from the northwest (not that unusual at this time of year). In the situation shown above, the solid red line represents the course for the Peterson 44. The black squares are the positions on the isochrones (which you can turn into a series of waypoints a route by highlighting with the arrow tool, and then going to Navigation on the menu bar and selecting Convert to Route ). Notice that the Peterson has a straight shot at the end into port. The Columbia, being six hours behind, has to tack. Beating at the end of a long passage? Yuck! 151

10 USING MULTIPLE WAYPOINT ROUTINGS One of the helpful features added in SetSail-MaxSea edition 9.2 is the ability to specify multiple waypoints for a routing. This can be used when there are navigational concerns, and you want to force the routing to avoid a specific area. Or perhaps it is weather, and you want to orient the course towards or away from an area of expected (light or heavy) winds different than what the GRIB file shows. Since routings are easy (and fast) to run, in many cases it is going to be best to allow the computer to choose what it thinks is the best course, with just a single waypoint. And then, after you ve evaluated this route, add waypoints and do another routing. For racing, there are a different set of issues these typically being course markers that must be rounded in a certain order. How Multiple Waypoint Routings Work SetSail-MaxSea uses the same basic algorithm to calculate optimum course, given the weather and performance of the boat. The difference is that it starts and stops the routing at each waypoint. It does this to the nearest whole isochrone line closest to the waypoint. So, the actual course is usually going to be a little longer or shorter than what you will need to sail. In most situations, this is not an issue, as you will be updating the routing with new waypoints or weather data on a periodic basis. By the time you are close to the next waypoint, the algorithm will be zeroed in much tighter. Bermuda to U.S. East Coast One example of using multiple waypoints is the trip from Bermuda to the East Coast of the U.S. In this situation, you have to deal with crossing the Gulf Stream, along with being on the correct side of warm and cold eddies. In the following example we re using the Next Generation Pilot Charts for June 1998, leaving at the end of May. If you were in Bermuda, you could go to the Harbor Master s office and pick up copies of the latest Gulf Stream data. But since we re doing this as a practice run, we ll use the Gulf Stream as shown on the planning charts. Waypoint W001 is on the south side of the stream, while W002 is on the north edge. We ve picked the narrowest part, as shown here, to cross. 152

11 The routing for the first leg is shown in the upper right image. Below are the isochrones for the second and third legs. Now, let s take a look at the route itself. With such a long passage, and at this scale, the best way to view the projected course is by turning off the isochrone lines. To turn these off, go to Performance on the menu bar, and then click on Display Isochrones. Evaluating the Routing One of the cool things you can do with SetSail-MaxSea routings is use them to decide when and how to go. In this routing, we re using the performance parameters of a Peterson 44, and assuming that no engine will be used. Winds are light, with a lot of varied work. A few years ago, you would have just left when the winds were reasonable in velocity, but with Routing, you have a better shot at choosing when to go. And this is not a good time, unless you want to spend a lot of days at sea working hard to gain ground towards your objective (we chose this particular scenario to show you how Routing works when you are faced with varied winds). 153

12 The first thing to note in the course (right) is there is essentially one long tack to the NNW in light running, before cutting back to the waypoint for crossing the Gulf Stream. Crossing the Steam itself is a series of short tacks going to weather. Then, at the end, we have some nice reaching conditions. I cannot think of a worse situation in terms of comfort than beating your way across the Gulf Stream. But if you have to do this, it is nice to know you have some good tools to help choose which tack to take and when. On the other hand, it would he one hell of a lot better in terms of comfort, load on the boat, and work for the crew to hang out in Bermuda, enjoying the sights, until a nice SW weather system established itself! Multiple Waypoints for Races The other side of using multiple waypoints is for racing. This is a natural for planning, and for use during the race itself. The only caveat is that the course legs have to be long enough to make the routing effective. (Note: the Professional Racer version of SetSail- MaxSea allows control of the time frame between isochrones which in turn makes tighter course practical. You can have isochrones spaced as close as a few minutes apart if required). Here s an example of a rectangular course such as you might find in an ocean race, We ll set the first leg dead to windward, and then a reach, ostensibly a run, and then another reaching leg to the finish. Normally the last three legs would be a parade, but in this case, the legs are long enough to allow for some change in wind direction and strength, creating a series of questions about which way to jibe and what the fastest angle 154

13 is allowing for the wind shifts to come. In the second image on this page (below) you can see both the isochrones and the projected course (in red). The first beat is shown as three long legs not a lot of wind shifts here. The first reaching leg has us sailing slightly high from mid-point, and then sagging back to the wayoint. The run is quite interestung. There s a jibe shown right away, then a second jibe pressing out to the west, before heading back to the mark. On the final leg, which was a run when we started, the wind has shifted behind us and so we ll be sailing a low course, then coming up on the mark (looking for best VMC). Route Lists In both of these examples, the details of the legs, every two hours, will be found by going to Performance on the menu bar, and then selecting Route Lists. 155