Scenarios
- Mixed fleet, medium airs
- Early or late or on time in fleet 1
- OD
- Light airs-early or heavier airs on time in OD
However I can just flow this into this section anyway, further to this, now we can presume we are at least sailing in a steady force 3 at design wind for the boat.' Presume it's an OD race (identical One Design boats that is) unless I refer to mixed handicap racing.
POST START- The First Shift
Okay, now we have galloped off the start line things seem to settle down. This is the perfect race for my level so we have at least clean air but we have probably not positioned for THE perfect start at what seemed to be a slight com'boat end bias.
Now I come back to what I had missed out on in part I: The gusts. In force 3 we can expect peak gusts of around about 12 knts and it will be clear if the breeze is building because we will start to experience force 4 gusts more of the time. These gusts are very visible and in this case are coming with wavelets NEARER the bow angle. So in fact these are likely to be significantly HEADED. But the unwary or un-whiley, enjoys the buzz of waiting for the gust, feathering into it and getting the big apparent lift. Wrong, they have lifted but not as much as any boat in the vacinity on in this case port tack. They have enjoyed BOTH a relative wind lift and pinching ability and the actual directional lift. In OD this can mean several boat legnths.
Why are the gusts backed instead of headed on starboard, given this is the Northern Hemisphere?? Theory states that the stronger, true wind is brought down from above where the coreolis effect means it is more spun clockwise. However there are so many mitigating factors- it can indeed be the true-er wind direction but the local bend effects are potent enough to funnel a breeze into more clockwise (dextral) direction of flow rather than the usual friction effect allowing for a backed-low level btreeze. For examplee....that is.
So the gusts on the day need to be assessed and this is also a job for the practice beat and the navigator. In OD it is a big pluss point or scoring card to tack and be properly set just in front of the first major gust if it is a header on starboard.
However we are in a fleet controlling position- we can cover all the late and pin end starters
In a little less wind, of around force 2 which may be an early sea breeze for example, then the gusts may be less evident, either long and slow or not of any real benefit. Here and in an overall weahter situation of frontal weather there may be in addition to gusts an underlying pattern, to which gusts are mere underdogs. That as in the case above the gusts are backed (sinestral, anti clockwise angle from the prevailing wind) can be a sign that
1: if the wind increases under a cloud pattern, then it will back and port will be favoured in that block of wind
2. conversely, if it slackens down a bit, the wind will go clockwise and the RHS and starboard will get you to the weather mark first.
3. There may be a new weather front or prevailing wind fighting it's way in at higher altitude which also suggests the backing and tactics in 1 but this will last maybe the whole race if the committee don't see fit to reset the windward mark.
True Shifts
Now what most often happens in frontal, anticylone hemisphere weather is that there is a pattern of shifts over any given 20 mins , about a first beats worth on most courses. So if you get fast off the line it becomes clear if the wind goes right that you need to get over there and the aruthmentic of boats ducked versus gain on the lift pays IF you are at the head of the fleet.
BUT it also pays if you are at the back of the fleet. In fact it pays anywhere as long as you can shake off any really bad offenders "farting" on you as they say in Norwegian. Tacking on shifts and before a known gust header pays if you can keep free air.
no shifts??
All else being equal though, and given no apparent gusts at the time, we know the bearing from the line to the mark. We can presume we sail at worst 45' and with any tide effects we maybe only do say 48' with leeway taken into account. We do however POINT at say 38' best and tack through about 82' on average. So we can choose to play it safe given our superior boat speed, courtesay Miss Free Wind!
All else equal? Go for the Cone!
What I preach here takes some deiscipline and on water arithmetic to do, but is worth it. Given no real tactical advantage in tacking I will in this race use a 60' cone to tack up.
To simplify this- you know about laylines and these can be set arbitarily as a 90' cone or sector from the weather mark. If you go way out, Scott Chalmers Style, to a layline quite early in the first third of the sector then you risk all by being hit by even a small wind change putting you on a header all the way. So to give a 'no brainer' or automaton type tacking theory in even wind direction, you tack up a 60' cone instead.
even wind would be wind shifts of less than 5' which last less than say 45 seconds- a random, repeatdely osciallting wind. At really anyones level. less than these levels makes it meaningless to tack on shifts derived from the compass. For my level , More than this to say, 6' with a one minute duration would be worth tacking on in a boat which holds speed out of tacks and in a one design fleet - or of course when BOTH tacking on a header AND doing some nasty tactic or avoiding another boat or shadow is desrirable.
Tacking up the 60'cone means that you are meeting a bearing about 27-33 degreesm off the bearing to the weather mark(90' fromt he start line most likely) , at your midships to the mark. At your first line out from the start a 60' cone gives you quite a wide sector to sail in before you hit this 'time to tack ' bell ringer! So you capitalise on your boat speed by sailing as long as you dare in this even wind direction.
As you come back across the fleet on port now you still have superior boat speed until you meet the first, short shadow from opposite tack boats crossing in front of you, or cheeky chappies trying to lee bow you if you are just ahead of everyone!
Now you can feed tactical information into those brains down the rail and up to you on the stick.
In OD, it is usually undesirable to duck another boat unless this avoids conflicts ahead of you ( given this lovely even breeze and no real benefit in going right for you at the head of the fleet). Especially in dinghies, the boat which crosses you has the option to blanket you or at least cover your direction. What you want to do is tack to avoid their wind shadow.
Now given you have just tacked and they tack away to cover the rest of the fleet you can sail on to your 60' line to the left or once you have separation for any conflicts to the right, go back over that side. By now most of the fleet will have gone right on the starbord rounding course, just because it is safe and they are sheep. No one wants to be on the left side, looking like a spare dick at the dance. So it can pay, now you have tacked away from your first threat to go the hell over right and cover much of the fleet and play with any top guns who came off the blocks RHS and kept there.
Your second tack up a 60' cone is by virtue of a shorer than full cone start line (most hell often) meaning that the first tack is shorter. So to keep free air you can afford to tack. Otherwise you can once again capitalise on your free wind boat speed advantage by sitting on this long leg all the way an above most of the fleet. Many of the starboard tackers who are top guns will now see you as taking a long, long stitch to go right and worry if 1. you will get ahead of them 2. you are going desperately right because you know it pays. This second tack then can send a whole pile off them off towards the layline and into firstly the danger zone for unwanted shifts and also force them into too many tacks.
The 60' cone is by the way, the shortest and quickest way to the mark in a constant mean wind direction, given that you start at least a third of the way down the line on a starbord dictated start.
So say the bearing 90' from the mid line to the mark is ooo' that is 360, due north, then you sailed into that exact wind direction. So starboard has been 310-320 say while your first port tack has been 40-50' E. If you sat on the lay line then this would be the angle from the bow to the mark. Sitting on your midships, the angle for a 60' cone is therefore calculated as about 330 degrees. You would need to sail a close 15 degrees to be ablt ot tack and make the mark ie. stand on the layline.
After this long second, port tack comes to the inevitable 30 sighting on that side of the cone, you will now have most boats behind you, or ahead but below you, with maybe some guys ahead and above you. Work out what the likely wind shadow would be if everyone tacked over and work out how far it is until the cone alarm goes off again. You can then make a call on average how many boats are threats on starboard versus how many may cover you if they tack ahead. Simple arithmetic means that if you can get over right to the cone you will tack less often. Pychology states people will have seen your long second tack and want some of what you are heading for. And tactics dictate that the top end of the fleet wil try and cover you and blanket you if they can. Starboard boats are more threatening because they have rights and can tack on top of you. As port boats draw nearer to your clean air, fast line then they can well tack to get you on rights or double tack to cover you, but that looses them time and in most boats some windward VMG.
Now you have reached the next 60' line you are in the thick of the top end of the fleet. Two boats are a good two tacks ahead of me...damn, maybe they were early anyway. I have one starboard boat who was ahead and has tacked and now bears down on me trying to get close by footing off. I then have a stramash of port boats tacking over to follow the leaders. I foot off a little and get max speed before using a little gust to come really high up on the boat on my windward quarter and establish clear ahead and force him to my line and then below me in my dirty wind. Inow am on the 30' and tack immediately, forcing him out towards the layline and those other starboard boats above us now.
Keep to your Strategy until Tactics Take Over
Now I once again choose. It looks like four or maybe just three tacks until i can sail onto the layline. Most often an average sailor will want to avoid the 'death slot' that is coming in on port to the layline in an OD fleet rounding the windward mark to starboard. But hey, we are at the head of the fleet. ALl the sheep are heading right and we have virtually clean air left. So we stay on starboard and go the whole way over the cone. NOW boats behind see our gain and REALLY start to have an inferiority complex and come over again to starboard. We hit our cone a lot quicker on the LHS now. Also we are coming out of tacks even better now and I am feeling the boat much better so have optimum VMG in this tideless, skew-less race!
The Windward Mark
In fact now we can see the windward mark and since we are talking big OD fleet in this fantasy now, the trip or off set mark. We hit our 30' signal and come way back over on port, past a few boats who were threats. Suddenly we can see that there are only three tacks again and we could go out now and sit on the layline. The wind has died about 2 knots so we carry on to the layline and suddenly there is only clear water ahead of our bow. A few more boats are on starboard but have sailed too far. Others have not changed gear for the lighter wind and have more sea on starboard so we can sail over them. Now we can make for a safe lay line call by tacking with the bouy over my back shoulder when I turn quite hard around to see it, rahter than my front shoulder.
We tack, we are fourth boat. The one starboard boat we ducked earlier did a lone tack to the other side of the cone and kept ahead of us. The two lead boats are slowing each other down, by taking an extra tack to try and guess the layline and then by trying to get an overlap call on the go. The inside boat fails here but gets a better grip to go low and then high and establish overlap on the off set mark, forcing the other guy to abandon hoist, which the challenger also must do. Boat three just sails on making a big gain as do we, with a string og boats high, low and just about right for the lay line behind us. Nice feeling, beign at the top eh`?
GybeSet Stratetegy- Modified by Tactical Considerations
Now the wind has built again and it is a lift on the layline. This gives us confident speed around and down to the trip but means it is likely a gybeset. We see much more wind coming right, and feel a 12 knt gust rustle through so to keep some clean air, get a good acceleration under kite with a clean hoist and fool much of the fleet into going left ( stage left now!) we bear away hoist. Everyone sets for this. The clump of ten boats behind us nearly all do this bar a couple who get stick in the bad air on their nice tight gybes and have trouble hoisting then go off in pursuit of each other. We see the chance while the kites settle and go back to the RHS of the course in a better angle and in air only disturbed by far off OD boats beating in.
The Leeward Mark
This pays all the way to near the gate when it swings back. So we now gybe and reckon with Left being favoured. We can make a nice straight line in on starboard to round on the LHS bouy on the leeward two bouy set up. In doing so we force our two clever rivals to come high and go right or follow us up the beat in our dirt. At three boat lenghts we drop kite and close the hole then bearing off to make a final, smooth rounding. The guy behind us has dropped later and comes in at speed on our stern, so I tuck the boat up into a luff once... twice and he is in our dirt. I bear away for speed and to further frustrate him and he tacks off, back into a fleet of starboard spinnakers!
The Second and Last Beat and down on our own!
We go right and play both the gusts and the shifts to end up about three boat legnths ahead of the other boat back us and five from our leeward mark challenger. The wind heads like a sod, and we have to tack to make the mark. This means clearly a bear away hoist and this takes us out into a really fast track in completely free wind. A pile of reasonable boats are on top of #2 and # 3 making their wind a bit dirty, with the national champion on their heels!
The wind dies a lot and we gybe in the last little gust we have to make best VMG. Then we ghost in gybing on the lifts to avoid the gate and come in to a nice finish, gybing to take a midline away from the canon fire!
BANG we WIN!!
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