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post #3 of Old 11-16-2012
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Re: StartLine Sailing Racing Android App

Originally Posted by allene222 View Post
Press Release
StartLine Sailing Racing Application for Android.

Arrive at the Starting Line on time at speed then continue around the race course with the Waypoint display.

StartLine by was created out of the desire for a better race start and my frustration with the solutions that were available. StartLine uses the concept of Target Speed (measured and entered during the prestart) to translate distance to the starting line to time, which is what everyone really wants to see. By using target speed the readings are still valid even if you do a loop to kill time and are heading away from the line.

StartLine was developed on the race course with an emphasis placed on low probability of error through simple easy to see and understand menus. Each display has a function and is not cluttered with other tasks.

Large high contrast displays make the StartLine easy to read under adverse lighting conditions.

Enter the starting time and if the race committee uses GPS time (which most do), there is no need to synchronize to any 5 minute gun, although the time is easily synchronized to any start sequence if required.

Ping the ends of the line then look at the distance and direction feedback to make sure it was done right.

Location readings are made more accurate by interpolation between GPS events and velocity correction of location. These combine to give extremely accurate readings of time to the line.

In addition there are eight starting strategies with a readout of the time to the selected start layline. This allows you to get in position minutes before the start so you do not have to kill time and speed at the last minute if you are early. This also gives you plenty of time to make corrections if you are late.

After the start, the waypoint display gives direction and time to the mark as well as boat speed and heading. Times take into account the course and compensate for the tacking or gybing required to get to the mark. The program allows multiple waypoints organized in multiple files in a very flexible format. Selection and editing or waypoint files are included in latest version.

For more information visit and click on the StartLine tab

StartLine is available on Google Play. Search for “StartLine” (one word)

Contact: startline (at)

Android™ is a registered trademark of Google Inc.
If it is not already incorporated, the most useful function I can see would be adding a Tacking Ratio/Start Sequence to establish ones start, a function my Timex Victory watch used to perform before it died.

One sets the "start time" and then near the start establishes a "tacking ratio" by tripping a timer as one crosses the starting line at the reciprocal of the preferred heading at the start, sailing along the reciprocal of the first course line for a time, tacking back toward the start line and tripping the timer again and then sailing ones preferred heading/course at one's best speed for the start and tripping the timer a third time as one reaches the starting line. With this, one has a total time elapsed, time heading away and time heading for the start which are used to establish the taking ratio (e.g. one might sail "away" from the starting line for five minutes and back for seven minutes, hence ones starting run is 5/12ths or 41.67% of the total elapsed time).

With this, near the starting time, when one begins ones final "Starting Sequence", one trips the "Tacking timer" as one crosses the starting line sailing away from the course for the last time before the actual start. Based upon the actual time remaining to the start, the timer sounds a warning a minute or so before the final tack back to the start and then a "tacking signal" when one should make ones tack. With that, one tacks and makes ones best speed back to the starting line and should hit the line at the exact moment of the start assuming the winds remain fairly steady.

For example, if one establishes the 5/12 tacking ratio, above, and one begins ones "Starting Sequence" 8 minutes before the start, as one crosses the stating line one punches the "Start" and sails away from the starting line for 8 x .4167 = 3 min, 20 sec. The "Start Timer" sounds the tacking warning at 2 min 20 secs and then again at 3 min 20 sec. One tacks and sails back to the start at ones best speed and should arrive at the line in 4 min 40 sec or right at the "Start" at ones best speed.

One can do the timing described above with a stopwatch but in a race, it almost requires a dedicated tactician/navigator with that job only and not preoccupied with "driving", trimming, or crew management.

Adding that to your App would be a very worth while effort.

"It is not so much for its beauty that the sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."
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