BBS 2009 – Day2, Race 3

Day 2, Race 3:

Current at the IRC D start is suppose to be a waning ebb going into slack water around  12:21 PDT with max flood at  15:44 PDT @  1.88 knots.  Weather forecast: The forecast speeds in the wind table are again near the model consensus for conditions in the vicinity of Alcatraz. The model consensus is generally for maximum winds in the racing area between 15-20 kts from 1400-1700. There remain some divergent models with max wind speeds in the low 20s and others only in the mid teens but these have not performed well the past few days.

Today we start first at the City Front Starting area. (Tracks from GPS)  Given the starting line is rather short, I called for a traditional Committee Boat end start to keep it simple.  We had a good start, right on the line with good speed on a starboard tack.  Given it’s a waning ebb, our intent was to stay in the deeper waters of the South Bay taking advantage of any flow from the South Bay flowing towards the North Bay and then try to go north-west side of Alcatraz to catch the remaining part of the ebb current from the North Bay.  The main thing is to avoid close to SF shoreline in case there’s early flood eddies developing.  Most of the fleet followed suit with this type of plan with the exception of Bodacious who tried to go north first near Alcatraz.  Tupelo had started at the pin end with clear air and in looking at their tracks, it seems they had good consistent speed as well – in the crossing from Treasure Island to SF shore, Tupelo had gained over 100 meters over us and we had gained over 100 meters over the third place boat(s).  As a result, Tupelo Honey captured the lead early on the first beat and we are in second place.  As we approach the City Front, we watched Tupelo sailing closer to shore while we were further upwind and behind.  To encourage Tupelo to sail further into shore, we stayed on starboard until they tacked over and we did the same. We then sailed on port towards Alcatraz with Tupelo, but Tupelo tacked back to SF shore about half way across the channel, we decided to continue towards the north side of Alcatraz as there may still be some residual ebb current from the North Bay while it’s unlikely  there’s much ebb current at the City Front.

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This is beginning to look like a match race series rather than fleet racing as Tupelo Honey and Inspired Environments kept trading places with each other on the race course as I scoped them out via the hockey puck as we sometimes gain in bearings then lose it.  But the use of the hockey puck compass bearings is a great way of ascertaining whether my tactics works or not.  As I had hoped, by sailing out north of Alcatraz, we caught some ebb current and was able to reduce Topelo Honey’s lead from 110 meters to leading the fleet on occasions.  By the time we tack back towards City Front we were just ahead by half a boat length, Tupelo tack over to leeward to cover us tack for tack.  Approaching Chrissy Fields, we sailed close to shore to see if we can find some favorable windshifts but with Tupelo in close cover all the way to the weather mark, it would have been a huge header that would benefit us.  By the time we rounded the weather mark, we were right on their stern as we gybe out towards central bay for more pressure.  Tupelo gybed out to the north to get more pressure, we followed suit to cover, but trying to stay inside so we can sail a shorter distance while still give them some dirty air as they gybe back to the Fort Mason Mark.  In the mean time, Kuai and Bodacious and the rest of the fleet sailed a rhumb line towards Fort Mason, in looking at the tracks, they did not gain much by sailing a shorter course in lighter air.  By theory, they should have experience some early flood at this point, but either they didn’t sail close to shore enough or the wind pressure is too light compared to mid channel.  The positions of the fleet did not change much during this down wind leg and at this point, we are in second place and we have only to try to dislodge Tupelo in their first place as we are always within 1-5 boat-length away, while the third place boat is about 400 meters from us.   So as we approach the weather mark for the second time at around 1:15PM which is about three hours prior to Max Flood, I decided it’s time to split from Tupelo and see if we can find the early flood current inside close to shore.  So we did not gybe and let Tupelo head out to the central bay, while we aimed for Anita Rock to see if the early flood can help us.  As in all tactical decisions, there is no one answer:  On the inside course, we had lighter winds but perhaps a little early flood to help us along, sailing on the outside course, Tupelo had more pressure, but sailed a longer course and perhaps encountering some residual currents.  As the track archives showed, Tupelo sailed all the way to Alcatraz before they gybed to starboard, while we sailed a rhumb line to St. Francis Yacht Club then gybed to port for a nice broad reach for the finish near Treasure Island.  As Tupelo and IE converged near Blossom Rock, Tupelo was about 100 yards ahead and they gybed in front of us to keep between us and the finish line.  We were able to close in on Tupelo, but were not able to beat them across the finish line:  Tupelo finished 14 seconds ahead of us and corrected out to 1:41 ahead on handicap.  So another second place under the belt as we approach the mid point of the racing.

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