To many skippers the pre-start and start are the most enjoyable part of racing. The combination of congestion, wind shifts and judging time to cover a distance makes the pre-start a time to maintain focus and not to engage in idle chat. Your wind shift information gathering process begins with the pre-start.
- Outline bullets
- Assess the favored starting tack
- Assess the entire course and especially any local tides
- Using the concentric ring radar overlay to time your start
- Preparing for a port tack start in a predominantly starboard fleet
- Planning your close-hauled starboard course to the start line
- When the stream (current) is strong
- Take your penalty early
- Start noting the timing and range of TWD variability early
- The P flag and why a rule 30.1 penalty is benign
- Spinnaker before start - check the SI
- Why we like to see TITS
- Making the most of restarts
Favored starting tack Edit
Even when the first leg is directly upwind of the start line small variations in wind direction will usually result in one tack being favored over the other tack at the start. Starboard tack is traditionally the favored tack (because of Rule 11) and for this reason either or both the wind direction and/or the distance to the first mark from the left-hand end of the start line had better be extremely favorable before you choose to start on port tack.
Perhaps the best reason for choosing to start on the port start is when the left-hand end of the start line is closer to the first mark than the right-hand (committee boat) end. When you consider the number of boat lengths that you lose as you slow down during a tack this can be an easy decision to make. The longer the start line is the longer you can remain on port tack before needing to give way to the majority of the fleet on starboard. If you've been timing the wind changes then this might turn out to be a tactical advantage.
When a start line is long relative to the distance to the first mark the most favorable start may be from a point midway along the start line. Usually this situation calls for a starboard tack start simply because you'll have less time on port before needing to give way to the boats that started on starboard tack.
The final consideration has to do with tidal stream. If you used the pre-start times (plus any restarts) wisely then you'll have an idea of where the the current is strongest. If one side of the course is assisted by a tidal stream then the extra couple of knots may be a significant advantage. If one side is disadvantaged by tidal stream then this might motivate you to start at the opposite end of the start line to avoid that handicap.
Assess the course Edit
Perhaps when you first start racing you'll be following the rest of the fleet and you may be content to play the classic "follow the leader" game. However, as you improve, you will find yourself out in front and if you haven't developed a habit of planning your preferred course ahead of time then you may lose that hard-won lead due to a bad course decision.
Some people might enjoy researching the course within the track editor while others might enjoy sailing the course and learning through repeated experiences on the same track. Whichever method you choose the idea is to prepare yourself with mental or written notes about which parts of the course will expose your boat to strong current. Then you plan your path around the track to take advantage of known local tidal stream as well as anticipated wind shifts. Usually tide will flow the strongest in the deeper channels and flow the weakest in shallow areas such as close to shore. At least this is how it is in real life but in VSK the courses/tracks are made by other players and so you may come across some truly bizarre situations. Don't be phased by those counter-intuitive cases and trust your instincts.
- If there is a narrow passage between two islands then the odds are the tidal stream will be strong in that passage so find out which direction it is flowing and use that information when you choose your path around the island.
- If there is a sandbar extending offshore from a beach then you can safely assume the stream will be strong in a channel along one side of the bar and near end of the bar.
- Any outlet from an inland lake to the open sea is sure to have stream in the canal or river but that stream can extend out to see for a short distance as well.
The above discussion has focused on tidal current but a similar set of questions and observations can also be made for the prevailing wind as it moves around land masses. Unfortunately VSK does not do a very good job of simulating the wind shadow effect even around the steepest terrains. If the track designer does a decent job then you can expect wind to be stronger as it funnels or crowds between two land masses and weakest on the downwind side (lee) of a land mass.
You can be assessing the most favorable path around a course while waiting for the pre-start to begin and then focus on the local conditions affecting just the first leg once you find your boat on the water during the pre-start. If the host announces early on their intent to restart at -1:00 on the clock then you really should take advantage of the present pre-start to explore the tidal streams en-route to the first mark.
Calibrate radar grid units Edit
If you aren't using a radar screen with concentric circles and a square grid then either visit Northspace.co.uk to download one or try File:Customize-najevi.zip which the author uses. It contains a customized version of
The square grid and the concentric rings share the same unit dimension and so you can use that fact to time how many seconds it takes at the present SOG to cover that unit of distance. Armed with that number you can judge your time to the start mark by counting rings as you sail directly towards it. Note that SOG is more useful than BS because SOG combines the effects of tidal stream and boat speed.
- Assuming your planned approach to the start line is the starboard layline to the RC (race committee) boat then ideally, that would be the course you sail when calibrating your current radar zoom. (Later on we'll discuss what to do when that is not practical.) We'll sail away from the RC boat at 150 TWA so when we turn back we are on a 30 TWA layline to the RC boat.
- As you approach the RC boat watch the radar view for that moment when the blip for the RC touches one of the concentric rings. Note the current time and SOG. (You might note this with pencil and paper at first but before long you'll be doing all of this in your head.)
- Monitoring the SOG you are watching for that point of your approach when your SOG has peaked and leveled off.
- In this illustrated case the SOG keeps increasing right up until the RC is 2 grid units away from the center of the radar display.
- Since the SOG kept increasing we'll take the second last SOG and the last and third last clock readings to calculate the number of seconds it takes to traverse one grid at that boat speed. This is a crude averaging process. If the pre-start is 5min or longer then you have more time to calibrate and so can commence your approach from further out to give your boat time to reach peak speed and level off. (You can also save time by skipping the first step and sailing directly from your spawn point to the starboard layline.
In this case we see that one unit of radar grid was traversed in 13sec at 10.3Kts SOG. Knowing this we can monitor the time remaining before a start signal and count off the number of concentric rings as 13, 26, 39, 52 seconds away from the RC boat. Of course you need to be careful to allow time to accelerate after a turn. It is better to have boat speed that you can bleed off by luffing your sails (using sail trim not rudder) because there is no way to magically add boat speed if you find yourself too far from the mark.
- A better way
- Even when you have enough time to do the above you can well imagine that if all 20 or 25 boats in a fleet are trying to do the same thing during pre-start then you'll be sailing the most congested water. So a better solution is called for.
If you don't already have a good idea of your boat's peak speed for the current wind speed on close-hauled point of sail then review the polar diagrams for your boat model. A ball-park figure is 10-11Kts. (Note we chose 10.3Kts in the previous example.) If you can sail 10-11Kts SOG on any point of sail then you can use the square grid overlay to count the number of seconds at that SOG it takes for any mark visible on the radar to traverse one grid unit. So as you sail from your spawn point to the starboard layline you can be calibrating your "seconds per grid unit" at a nominal 10 knots SOG.
This works very well so long as you don't go changing the radar zoom! It turns out that each click of the zoom in/out changes the scale by a factor of 1.5. If you have a course mark touching the 2nd concentric ring then zoom in with the (+) button then that mark snaps to the 3rd concentric ring - a scale of 1.5x.
An enhanced radar zoom AutoHotkey script can help you keep track of which radar zoom you are at but this works only if you exclusively use some keyboard key to zoom in/out and never click the GUI buttons with your mouse cursor. Basically the script asks you to input the time to traverse one grid unit (in seconds) and the average SOG (in knots) for that traversal and it stores the product as an integer knot-seconds / grid which is then displayed briefly as a tooltip each time you change the radar zoom. For any given SOG you divide the knot-seconds product by the current SOG to calculate the seconds per grid unit. So if the tooltip displays 225 knot-seconds and your present SOG is 15.0 knots then you know that one grid unit is traversed in 15 seconds and 4 grid units in 60 seconds or 1 minute. The AHK script takes care of modifying the displayed knot-seconds product by the 1.5 factor each time you press the hot-key to zoom in or zoom out. For the script see the AutoHotkey article.