Roll Tack

Back to the serious issue of dinghy boat racing!


I mentioned before that we seem to loose a lot of distance when tacking against the Lasers and I think I now know why. Many reasons.... but principally it is too much rudder. Sounds odd as you would anticipate wanting to turn as fast as you can to pick up the wind for the next leg.

This weekend when on board the Topper Xenon with the Bar Man, we did some reasonably quick tacks and it was noticeable to me at helm that the boat seriously digs in on the corners and slows down (Chine technology?). I had heard of a roll tack but couldn't remember quite what it was.

That was until now.....

Roll Tacking Basics (video at end!!)

Roll tacking is a method for getting the boat through a tack quickly, without losing much speed or ground. Listed below are three basic advantages to a roll tack, which is used primarily in light air when boatspeed out of a tack is important. However, keep in mind this is not the end-all, be- all of dinghy racing. The best roll tacks in the world do not guarantee a win, and sometimes they can blow your concentration if they are used before you have mastered them.

• Roll Tacking Basics Heel the boat to leeward about 10 degrees. This initial heel allows the boat to turn itself, cutting down on the rudder usage necessary to initiate the tack. Don't heel the boat too far. The object is to turn the boat slowly enough so you can control the tack. During this step, you should be able to let the tiller extension slip through your hand, with the hull of the boat doing all the work.

• As the boat starts to come down on you, rock it hard to windward. Timing is important in this step. The goal here is to help the boat do what it wants. The biggest mistake you can make is to try to roll the boat too soon, "squashing" the tack, finding yourself head to wind, or on the same tack on which you started. This mistake costs much more than a regular tack would (and it feels horrible). Wait until the jib luffs and the boat feels as though it wants to come down on top of you. Then rock it hard. Rocking the boat to windward may feel funny, as though you're going to capsize. However, it's important to rock it this way. Sometimes the boat will stop the rock on its own, if you don't help. In fact, it may be good to practice this maneuver until you capsize a few times. If you're afraid of capsizing, your tacks will be mediocre. You must get the feel for how far you can go.

• The purpose for this step is to get the sail through the tack as quickly as possible. Notice that, usually when you're tacking, there is a long period of time where the sail luffs through the tack. This step will alleviate that luffing, with a telltale "pop" of the sails.
  Once the boat is on the new tack, and still heeled up from the rock, flatten it quickly. This is the heart of the roll tack. The rock should have put the rail of the boat in the water. Now, when you flatten it, you are pulling the sails through the air, effectively increasing the wind speed over them. This gives you a nice push forward, accelerating you out of the tack. Note the position of the sails. They should be trimmed in during the flattening, but not all the way. When this "wind" is created, it acts as a lift, so the sails should be eased slightly. Then, when the boat is flat and up to speed, trim in the sails to pointing mode again.

• This flattening should be done after the sails fill, but as soon after the rock as possible. With the boat up on its ear at 45 , it will slip sideways very quickly. Just watch someone who doesn't flatten immediately. They will lose a lot of distance to leeward, much more quickly than you would think.

That can sound quite complicated if you are not used to nautical terms so here's a video demo.



Could the Bar Man confirm we're okay to do this next outing and I'll report back of progress against the Lasers.

Ipswich Dock

Sailing on the East Coast isn't all muddy banks, creeks and difficult-to-navigate rivers. Yesterday on a blazing summer's day I found myself at Ipswich Dock which is or has been one of the largest regeneration projects in the East of England....!

Mrs Hook and I boarded the Il Punto, which is "a renown French Brasserie alfloat and moored alongside Neptune Quay at Ipswich Marina".

The food was fantastic and so was the service. My only complaint was the weather was just too hot!! Anyway this made it impossible to tell that we were still on "Mud Island" and it was very easy to imagine being in Antibes again (which by the way has a very interesting looking Yacht Show).

Unfortunately this has rekindled my interest in getting a bigger boat to sail on.

Lunitidal Interval

Even Pirates have Birthdays; fortunately Mrs Hook has taken very seriously my woes about crossing the start-line last everytime. I now have a sailing watch to rectify this! [thank you Mrs Hook]

Now it is not only the countdown alarm which is going to be useful for telling when to cross the startline, but it has the very handy facility that shows you what the tide is where you sail. From my earlier blogs you'll know it is very important to get this right. All I had to do was input

1. GMT Differential +0.0


2. Longitude 1'0333'' E
   
3. Lunitidal Interval ??
   

If you are like me you'll have no idea what the Lunitidal Interval is and why should you because I don't think anyone does unless they buy a watch that displays what level the tide is at.

Still guessing? [so am I]

The Lunitidal Interval is the average time difference between when the
moon passes over a time meridian and the following high or low tide. If the time meridian referenced is the local time meridian, then the lunitidal intervals are called the "Local Intervals." If the time meridian referenced is the Greenwich meridian, the lunitidal intervals are called the "Greenwich Intervals."

Generally, the manufacturers of such items use the Local Intervals for their calculations. Our office does not track or maintain the
Local Intervals; we calculate and track the Greenwich Intervals for various locations. This information can be found in the Datums
section of our website.

The Greenwich Intervals we provide can be converted to the Local Interval using the following formula: Local Interval = GI - (0.069 * L)
Where L is the longitude for the location in degrees. West longitudes are positive; East longitudes are negative.Example: 122 degrees 23.7 minutes West would be
122.395 degrees. (23.7 / 60 = 0.395)
Longitude for a station is available from the Accepted Datums page by using the link provided for further station information. Where GI is the Greenwich Interval. To calculate the High Tide Local Interval, use the Greenwich Mean High Water Interval in Hours from the Accepted Datums page. To calculate the Low Tide Local Interval, use the
Greenwich Mean Low Water Interval in Hours.

Some products will require the Local Interval to be a positive number. You can convert a negative interval to a positive by adding 12.42 to the result.For example, if your interval calculated to be -4.11; you could also use 8.31 (-4.11 + 12.42 = 8.31)

The Highest Tide normally refers to the highest tide for a particular year. For practical purposes, there is no single "highest tide" for a year. Depending on the location, there will be between 2 and 8 days during the year when the high tide is at it highest predicted height for that year (with a precision of 0.1 foot). We do not attempt to track which day(s) this will occur on as the date and time may be different for each location. You may determine the date of the "highest tide" for your uses from the High/Low Tide Predictions section of our wesbite. After selecting the station you are interested in, you will be provied the times and heights of the high and low tides for that location through the entire year. In general, the highest high tides and lowest low tides occur around the dates of the New Moon and Full Moon; these are known
as the "spring tides". Dates of the New Moon and Full Moon can be found in the Astronomical Data section of our website.

Insurance

Insurance one of those things you wish you didn't have to bother about. Well actually you don't but taking that decision means that you accept the risks, that's how it works.

Now I read this last week about a chap who was stopping at every port in the UK as he circum-navigated Britain. Unfortunately he came a cropper when he ran aground in Dorset and the yacht was a right-off. Apparently he had no insurance and had a load of cash onboard to sustain him on his trip.

Click here to see...

Video - Colne Estuary

I found some more clips on YouTube and think they are great. They show where I sail, all thanks to Dylan Winter (dylan.winter@virgin.net) - no I don't know him, but just giving credit where it's due!

Video - Wivenhoe to Colchester

Blimey - the water where I sail is famous and appears on YouTube!!

I found this video on YouTube which pretty much follows last Sunday's race. I reckon it was taken one of those weeks where I was unable to race - some of the boats are in the pictures Mrs Hook took on Sunday.

I am now blessed with a wealth of new facts about where I live; Mrs Hook's parents will not be pleased that Britain's largest recorded earth quake took place where they live and I also know why I described the turning at the buoy 'the arse of Colchester' - you'll have to watch the video to see why. Finally looks like I might need to move to Rowhedge!!

Handicap System

I have discovered that it is not just enough to have the most pointy-fastest boat in the club. There is another thing called the handicap system which I must over-come.

Today's race took us up to the Ancient Roman Port of Hythe, yes up to King Edwards Quay in Colchester (who would have thought that Colchester has a port). In short, lovely sail through green fields to finally turn at the dirty arse Colchester bit. If someone dredged that bit at the top where we turned, there is a fortune to be made out of the marina that could be there. Instead Colchester has opted for the VAF further into town - read the link, I know which one I'd prefer.

Anyway, all was going well until we reached the inevitable turn. Another nautical lesson learned here about which object you refer to in sentences when going around port side - to me it is ambiguous as it could be either the boat or the buoy. As race rules stipulate, having gone round the wrong side, I had to perform a 360 spin - time lost but not too bad. We were still doing well and were vying for the lead. Unfortunately another disaster struck when we hit the mud, became becalmed and drifted into low hanging branches. We crossed the finish line 2nd, but the handicap system meant the Mirror that came last actually won.

So the handicap system is something I will learn to deal with in the next few races; for me and my crew (here on known as The Barman), we both agreed that we would prefer to cross the finish line 2nd than last.

BTW - going round port side means port side of the boat (I think my mind is set to look at everything from a different perspective).

Wivenhoe Regatta 2009

Last week it was hot, hotter than the Med....er probably.

Unfortunately I couldn't get out on the boat because tides, crew and my flight to Edinburgh check-in time could not be co-ordinated. However I did manage to have a meander round the Wivenhoe Regatta and take some snaps. It was a great day for sailing and I found myself quite jealous of the boats going by - there was a good breeze and was a gorgeous day.

The Wivenhoe One design is a boat and feature of the day. I always find it strange even though a small number were built, (about 20) they attract such enthusiasm from their owners and they have been kept going for so long. FYI they are the smaller looking boats with the red and white flag (burgee) on the sail. The others are 100 year old smacks that are sailed in the Essex, Thames area.