Racing start: how to set it right with simple mathematical calculations

In our last in-depth technical discussion we talked about how to reach the upwind layline as accurately as possible, but it all starts with a good start, which is the basis for setting a winning race. Once again to assess the position of the starting line with respect to the wind, and to choose at which point of it to start, we will be helped by trigonometry goniometry and simple mathematical calculations. There are now many software, applications and electronic tools that help us in evaluating the best area of the starting line in which to start, but knowing how to make decisions even without technological help is certainly the best choice.

The start in racing, how to evaluate the line

Two considerations are needed to understand how to evaluate the baseline. The first is to assess any fluctuations in the wind, and the second is to figure out if the line was placed correctly by the Race Committee or if instead there are small discrepancies that we can try to exploit. As with laylines, we will pretend for convenience that we have an upwind buoy placed for 300 degrees.

The starting line in theory should be positioned perfectly perpendicular to the imaginary line coming down from the windward mark. With a buoy at 300 degrees, if we run down the line pointing to the starting buoy this will detect it for about 210 degrees. Conversely the committee boat will be for 30 degrees. The straight line from the windward mark down to the start will form two imaginary 90-degree angles, in which case we will have a perfectly positioned starting line relative to the windward mark. If, on the other hand, for example, we survey the committee boat by 20 degrees, it means that the line is crooked, with a 10-degree advantage in Committee. It means that the Committee Boat is positioned higher than it should be, so it will be advantageous to start as close to it as possible because by doing so we will immediately gain meters over boats that start closer to the buoy.

We have only talked so far about the geometry of the starting line, that is, how to use any small discrepancies in positioning in our favor. There is then to evaluate the wind swings to complete the choice regarding our departure and figure out the best way to set it. Here is the calculation is very simple, given the buoy for 300 degrees, the wind direction must be noted: all numbers less than 300 will indicate wind swings to the left, all greater numbers to the right.

The choice on which start area to choose for the start of our regatta thus depends on two evaluations: the geometry of the line with respect to the windward mark and the average wind swings that we will detect before the start. Then there is also the parameter on the possible current, but we will address that in a further discussion.

Between line geometry and wind fluctuations, what weighs more in choosing the area of the line in which to start? It all depends on the magnitude of the two factors. If the wind shifts are constant and with significant oscillations greater than 5 degrees it may be worth investing all on this aspect, leaving out any asymmetries of the starting line. Conversely, a markedly asymmetrical line, again with differences greater than 5 degrees, is something that should always be considered.

It can sometimes happen that Race Committees, if they value a particularly favorable area of the course, for example the right, and anticipate that the whole fleet will be massing near the Committee boat for the start, deliberately place the line slightly asymmetrically. By lowering the position of the Committee boat relative to the start buoy when there are wind swings to the right, they will disadvantage the Committee boat start by making it somewhat less advantageous. Why? With a lower Committee position, and wind swings to the right, the risk for boat starters is to arrive too early on the line and incur an OCS, especially if there are many competitors to choose the right side of the start. By making such a choice, the Committee ensures that the fleet is spread more evenly across the line, avoiding excessive tussling at one spot on it and possible repeated uneven starts.

Mauro Giuffrè