June 16, 2005
June Series 3
This isn't what I would call a good race from several stand points. First, the wind shifted such that it turned into four beam reaches. No tactics, no strategy, just working the boat speed.
Second, I made a bad choice on the first "downwind" leg by calling for a spinnaker set. As it was, the wind was too far forward to carry. I bore off at the mark to help get the kite up, but that only cost us distance and time. We took the spinnaker down and went from speeds in the 4kt range to a speed just above 5 kts. But, the damage was done, and we we unable to catch the faster boats.
Finally, we had a bad start. I was above a boat and would have been pinched over the line if he hadn't been a nice guy. We also had poor boat speed at the start as well.
For this race, we had a Flying Scot, a couple of Vanguard-15s and a homemade catamaran finish ahead of us. It seems we managed to correct over the latter Vanguard, but I don't know how that worked out. They seemed a long way ahead of us and I was assuming we would be 5th.
The interesting part was that Cacafuego, the other Day Sailer in our fleet took GPS data during the race so I've processed it here.
All speed and velocity numbers are in knots.
| Surprise | leg1 | leg2 | leg3 | leg4 |
| start time | 18:35:00 | 18:43:12 | 18:52:11 | 19:00:20 |
| finish time | 18:43:12 | 18:52:11 | 19:00:20 | 19:08:35 |
| elapsed | 0:08:12 | 0:08:59 | 0:08:09 | 0:08:15 |
| hours | 0.136666667 | 0.149722222 | 0.135833333 | 0.1375 |
| nm | 0.655 | 0.668 | 0.668 | 0.634 |
| mean vmg | 4.792682927 | 4.461595547 | 4.917791411 | 4.610909091 |
| mean speed | 4.831 | 4.626 | 4.977 | 4.77 |
| mean angle | 7.221089778 | 15.32097044 | 8.84662573 | 14.83937586 |
| Cacafuego | leg1 | leg2 | leg3 | leg4 |
| start time | 18:35:00 | 18:43:06 | 18:53:43 | 19:01:19 |
| finish time | 18:43:06 | 18:53:43 | 19:01:19 | 19:11:04 |
| elapsed | 0:08:06 | 0:10:37 | 0:07:36 | 0:09:45 |
| hours | 0.135 | 0.176944444 | 0.126666667 | 0.1625 |
| nm | 0.655 | 0.668 | 0.668 | 0.634 |
| mean vmg | 4.851851852 | 3.775196232 | 5.273684211 | 3.901538462 |
| mean speed | 5.066 | 3.967 | 5.274 | 4.165 |
| mean angle | 16.71875976 | 17.88960108 | 0.62700147 | 20.48825989 |
In this table, the boat's initial letter is used to indicate which had the advantage.
| delta | mark 1 | mark 2 | mark 3 | Finish |
| elapsed time | C 0:00:06 | S 0:01:32 | S 0:00:59 | S 0:02:29 |
| mean vmg | C 0.059168925 | S 0.686399315 | C 0.355892799 | S 0.709370629 |
Since there wasn't much in the way of tactics, I'll note what occurs to me regarding the relative boat speeds. Jim had a better start than we did. His speed was in about 4.3 kts, ours was 2.8. Jim had better average boat speed on legs 1 and 3 while mine was better on legs 2 and 4. I was able to pass Jim during the second leg only because he also tried to set the spinnaker and had troubles with getting it down. It appear that when our boat speed was better was better, it was better by a larger margin. Jim did a good job of sailing to the mark on the third leg. His mean VMG was nearly the same as his mean boat speed.
It will be interesting and fun to see comparisons of this data when we have a real race.
Posted by Bob at June 16, 2005 02:27 PM