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Following up on the webpage of the suppliers, there is no mention of the Sabre class allowing these devices. It is quiet an expense thing to have onboard. Compasses have always been used in the class. What are the rules on this technology?
Hello Richard,
I have been looking at both the Velocitek and Tacktick setups. In my mind the tacktic compass is nothing more than an expensive tactical compass – being an electronic version of the glass ball compass. There is no GPS component. It merely shows your heading as a 2 comparative numbers to indicate headers and lifts.
http://www.tacktick.com/2007Tacktick/products/dinghies.aspThe Velocitek does contain a GPS component to measure upwind and downwind VMG. I do have a fundamental problem with this technology in the class.
http://www.velocitekspeed.com/The tacktick merely performs the same function as a tactical compass (as currently allowed under the class rules). The Velocitek however stores the windward mark as a waypoint to determin and display your upwind or downwind VMG. The storage or the mark location is in my mind contray to the spirit of the class. Could it perhaps be seen as verging on outside assistance?
Just my two cents worth.
Chriso
The carrying of GPSs is definately not permitted, but the TacTic has not been specifically permitted or outlawed.
On the basis that the Velocitek has greater capabilities than a simple compass I believe it is not permissable.
I will be asking the next AGM at Adelaide after New Year (or the meeting reviewing the rules) whether we want to permit TacTic compasses in the revised Rules – I recommend you wait till after that.
Mike Simpson
Well I purchased a Velocitek SC-1 from Andrew McDougall at KA Sail online and used it for the first time in a club race a couple of weeks before the nationals. It was $525.00 delivered. I needed a watch for starts and was considering a compass. The count down timer on it is awesome. Way better than a Ronstan watch which got stolen. The compass is another thing; I have never had one before and am therefore not really getting anything out of looking at it. It’s easier to look up at the mark and consider the angles. I didn’t need the count down anyway with those gate starts, just a timer from the start gun to get the rabbit at 4 minutes later, the Velocitek doesn’t count up after 0. There were at least two other boats carrying a GPS during racing at the nationals I found out after asking a few questions. I love the fact I could download my race onto Google earth and watch the race in afterwards and see how/where I was going. Did you know those marks were moving and we can only achieve 50 to 55 degrees to the wind with speed? There was a national title in Europe in which Velocitek sponsored and had every boat fitted with one. They then replayed the racing and see where all the boats went, how fast they where going and how the winners won by putting them all on the one screen! It does do speed, direction, VMG and tactical compass as well. I hit 12.5 knots in the blow. I do think the money would have been better spent on a new sail though! It is a great training tool and does make you see the faults you encounter out there afterwards. I don’t think they should be outlawed in the class. They don’t make you a better sailor on the water. Sailors will always want compass and watch, this has both at a good price. The VMG only changes be it a wave and you go so slow in a Sabre, they really are designed for the high performance boats to carry. They can be programmed to show only what you want or what is legal, eg timer & compass only. Anyway, I did show it to quiet a few Victorians after the races on the laptop and they seemed pretty impressed. I hope we don’t keep thinking we are in the 20th century still. They float, have 40 hours memory, update 4 times a second, use three AA batteries which last 20 hours or more, weight very little for what it is, well under a kg. and is very simple to use. It doesn’t save way points (the above post is wrong), it works on the wind direction you set on it which I find changes all the time and you can never get it right. I’m sure the prices will come down as they sell more. I think they have only been around for a little over a year. Anyway I think this subject can be closed. Sorry I posted it in the wrong part of the forum. See you on the water!
@Chriso wrote:
If it does not store waypoints how does the unit remeber where the marks are to determine VMG?
I’m not a sales consultant here, but you can see your track by downloading the stored data afterwards and reviewing it on a computer. It can only be assumed where the marks were, as that is the point where the track makes a total direction change. The track can be accurate to within a metre they say. The VMG is calculated by inputting the angle of the wind while sailing. This can be done in a couple of ways. Once you are close hauled, and you look at the VMG, it will theoretically tell you which tack is producing the best speed to the wind direction to which you stored. I find have to you reset the wind angle all the time to actually see the lifts and knocks; which then gives you the VMG upwind; is very hard. A reach uses the same wind angle you last set. If the VMG increases, you are sailing on a more proficient angle or doing something better; so I think. It definitely doesn’t save mark positions. See the following I have cut and pasted from their forum:
What do you think about to use Velocitek for to have the windward mark (and downwind also) VMG instead of the wind direction VMG?
Is it a good idea?
Ciao,
Domenico.
Sailboats have sweet spots where their velocity made good upwind and downwind are optimal. This is what every racing sailor wants to know. This is very easy to obtain with the Velocitek products. This is very difficult to obtain with a standard GPS that provide VMG to a user specified point.
Velocity made good to a particular point, ie windward mark, leeward mark, finish line etc, is of limited value when you’re trying to reach a mark as fast as possible. Consider the case when you’re sailing to a mark THAT IS DIRECTLY UPWIND of you. You must tack back and forth to reach the mark. Given that wind speed and direction and boat handling remain constant while you sail a close hauled course, your VMG toward the mark will continually decrease as you sail upwind. If you tack before the layline you’ll find that your VMG toward the mark jumps up initially, then continually decreases as you sail upwind. So if you were trying to use the VMG toward the mark to help you decide when to tack, you would find that every time you tacked your VMG would increase, which might lead you to think that you need to tack repeatedly. Whereas you would actually be quicker to maintain one tack on starboard until you reached the layline, then one tack on port to the mark. Fewer tacks would result in quicker arrival at the mark. Sketch a diagram of this and give it some thought.
Sailing your boat at it’s optimal upwind VMG is key to getting the most out of your boat, so you’re not pinching too much and going slow or beating or reaching too low and going faster but too mush farther.
In the real world. The direction that the wind comes from changes. When you’re sailing upwind on a starboard tack to a mark and the wind direction shifts counterclockwise, you experience a header and you should tack onto port which is experiencing a corresponding lift so that you will sail a shorter distance to the mark.
In the real world, the wind pressure varies on the course. Unless your sailing in overpowering wind speeds, your better to sail where the wind pressure and corresponding wind speeds are greater.
In the real world, you also need to consider the effect of wave height and frequency to windspeed. When the winds are light and the waves are bigger and/or more frequent you will likely find that not pointing so high will enable you to sail through the waves with better VMG upwind. If you have the option it’s generally better to sail in an area of the race course where the waves are smaller if the other factors above are equal.
In the real world, you may also need to consider the effect of current if it exists. Currents may be area specific and you need to consider their effect on your boat and what your goals are to optimize your performance. Current can speed you up or slow you down. Sometimes you have to fight your way through an area where the current is unfavorable to get to an area where there is no current or more favorable current.
The decision to sail on the right side or left side of the course or to the sail to the laylines etc should be based on your observations of which side has more wind pressure, which side is expected to have more favorable wind shifts. Tacking to sail the lifted tack when going upwind and jibing to sail the headed tack when going downwind are the critical to sailing the shortest course. The effects of waves and currents are also factors to consider.
We use the velocitek on our 1 design keelboat. We have to mark the boat and pin ends of the start line. If the unit is not storing them as a waypoint then I dont know what its doing.
:“Start Line Proximity Mode
This mode displays start line proximity in meters or boat lengths. Start line proximity is defined as the perpendicular distance from the bow of your boat to the start line. The user enters the start line into the device by setting reference points near the committee boat and pin.”Therefore it does save waypoints, but only for the start line.
I haven’t used this feature yet. Not much use in a dinghy.
@Richard Jackson 1660 wrote:
“… user enters the start line into the device by setting reference points near the committee boat and pin.”
Therefore it does save waypoints, but only for the start line.
I haven’t used this feature yet. Not much use in a dinghy.
Sounds like a cool feature though! Just what some members of the fleet at the Vic States needed
. It seems like the Black Flag is not enough of a disincentive any more so maybe we could wire up a such a system to a set of electrodes …Sabre Sailors,
Here’s an update on TackTracker launch and the GPS bulk buy.
I’ll be turning on the TackTracker web site very soon. In the meantime, if you’d like to take a look at the product documentation, the online version can be previewed at http://www.tacktracker.com/doc. Any suggestions or feedback would be most welcome.
Because the software is new, I have decided to offer a Beta program. Users who register for the Beta get free use of all features until March 1, 2009. The intent of the Beta program is to encourage people to try the software out, and to get feedback. After the Beta expires, the full license will be available for registered Beta users at $30 for a limited period. This will be less than half the normal asking price.
On the GPS bulk buy, I’ve had a great response from you. Currently I have 13 confirmations – and I’d like to get this to 20. We just need to get the word out, so if you know of people who may be interested, please pass this email on to them. I’ll be placing the order early November, so there’s still time, but not a lot.
Launch Package: (this is a once off!)
1. GPS
QStarz BT-Q1000 Platinum GPS Travel Recorder, with rechargeable Ni-Cad battery, AC charger, car charger & USB cable.
$120 + $10 postage, if required.1.
2. TackTracker Beta Program
• Available to everyone, whether or not you have a QStarz GPS and whether or not you bought it from me.
• Free use of all features until March 1, 2009.
• $30 full license available until April 1, 2009.The software will be available as a free download from the web site with lots of free features, but a license code is needed to unlock full capability. You can see what features are free and what is licensed at: http://www.tacktracker.com/doc/ under “Quick Introduction”.
If you wish to participate, please respond in the next week as follows:
If you’re a GPS buyer:
a) please send EFT payment to:
BSB: 063225
Account: 10305615
Name: Geoffrey M SmithMake sure you put your name in the Ref field, so I know who the payment is from.
b) Send me a reply email with the following information and I will enrol you in the Beta program:
*Your name:
*Address:
*Telephone:
*Email:
*Yacht Club:
Number of GPS units:
Postage Required @ $10 (yes/no):(Units can be picked up from Blairgowrie, or my home in Burwood)
If you already have a GPS, you can enrol in the Beta program with a return email including the * items above.
I will be back in touch with software download and GPS delivery details in early November. In the meantime, if you have any questions, please ask.
Best Regards,
Geoff Smith
[email protected]
0425 803 752[/quote]A quick update for forum readers:
1) The web site is up: http://www.tacktracker.com
You can download the TackTracker software and also register for the Beta program.
The “Races” section contains tracks from recent Sabre training sessions at Black Rock and Lindisfarne.
2) I’ve just received the first batch of QStarz GPS trackers. I still have some unallocated, so if you would like a tracker, please send me an email, geoff (at) tacktracker.com. Price is $140, plus $10 postage if needed.
Regards,
Geoff Smith (Aquila V)
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