I-36 Marina Village Cruise Rally - May 26, 2007

Your rally challenge, Matey, if you're seaman enough to accept it, is to predict your sailing time, in minutes, between the start at the Bay Bridge and your arrival abeam Estuary Mark 8 - waypoint #9 below.

Thus, if you went exactly 6.0 knots over the bottom, in a straight line, it would take you 83.0 minutes to cover the 8.3 nautical miles.

Each boat that registers (or just asks) will be emailed the Excel spreadsheet below. Then, before you leave home, or if you have a computer aboard, you can try different estimated speeds, and different speeds for different legs if you want. On the water, you can use a calculator to divide 8.3 by your chosen speed, then multiply by 60 minutes to get your prediction of the number of minutes you think your trip will take. This can be a challenge because, depending on the wind, you might have to beat on some legs, get wind shadows on another, and be on various points of sailing on different legs.

Here's a suggestion for those that want to play the game. Get to the starting area a little early. The wind at the starting area is typically (way) less than the first two legs of the course, then it's down wind a little, and reaching behind Treasure Island in smooth waters, blanketed behind Yurba Buena Island until you are going downwind in the Estuary. So, you've got the magnetic courses for each leg shown below. Sail for a few minutes on each angle shown in the table below and record your speed. Then put that speed into your copy of the Rally spreadsheet to get a time for each leg, and a total time.

Add your Secret Number to your predicted minutes and write it down - this is your Reporting Number.

Then, just before we start, the Rally Coordinator will conduct a radio roll call on Channel 72 to collect the Reporting Number from each boat. Since each boat has a different Secret Number, no one will be able to figure out what the competition is predicting.

After the Coordinator has recorded all times, she/he will announce and record the official start time which will allow for at least 5 minutes to prepare to start. The starting line will be between the Bay Bridge tower east of the center block and its northern-side red and green guard nun. Yachts shall cross the line in a westerly direction - probably on starboard tack - leaving the nun to starboard. (Waypoint # 1 below.)

You must observe each waypoint along the route, leaving each to the side indicated, then passing abeam of Estuary 8 within three boat lengths (waypoint # 9) leaving it to starboard.

As each boat passes waypoint # 9, they will broadcast their time on channel 72 and write it down. Other boats will check their watches (or better yet, their GPS time) and visually confirm that the boat is actually passing the mark.

When you get to the dock, turn in your finish time to Rick or Sandy. Prizes will be awarded at Saturday evening's dinner for the boats that get closest to their prediction.

All yachts shall try to sail the course. If the wind happens to be light and speed-over ground drops below 3.5 knots for 5 minutes, the Coordinator will authorize engines to be turned on for the current leg of the course only. If the wind has increased to permit sailing with an SOG above 3.5 knots, the Coordinator shall declare that engines must be turned off at the next waypoint, otherwise the Coordinator will authorize engines to be continued for the next leg of the course. This determination will be made for each leg individually.

Engine speed must be set wherever you like within 5 minutes, then not changed until you are told to turn engines off, or have passed waypoint # 9. If engines are turned off, then on again later, they shall be set at the same RPM as the first time the engine was used.

Rally spreadsheet example.