Tools for Setting Marks for Yacht Races

[Laser3]

I have developed a New Free WebApp tool to help race officers set up the marks for yacht races. You simply enter the wind direction and the windward leg length, and the tool provides the bearings and back- bearings for all Marks => for Both Triangle and Trapezoid courses. Another option provides lat/longs for all Marks after the user clicks a Geolocation button at the bottom mark as the reference point. No more fiddly tables.
I would like to get some feed-back on it.

See

https://www.setcourses.com

some examples

Simple Triangle 60-60-60 =>

https://www.setcourses.com/triangle60.html

Triangle Lat/Long

http://www.setcourses.com/triangle_latlong.html

Trapezoid Lat/Long =>

http://www.setcourses.com/trapezoid_latlong.html

Cheers

John

 

[lw395]

1) Lat/long format could be more usefully DDD MM.nn?

Different RO's seem to use different reference points, either the windward mark, committee boat, centre of start line etc.
The question being, what do you try to keep constant if the wind changes?
It's crucial IMHO to be able to move the windaward mark after the first beat, but also handy to be able to move the leeward end.
Often you want to keep the committee boat fixed as a reference, but OTOH, we often move it to the finish line.

In our world the wind is only used in units of 5deg, and we can add 55, 60 or 65 degrees in our heads to put the gybe mark in, and subtract to get the bearing from the leeward mark.

You might want to consider the ugly option of marks to starboard, it can be necessary.

 

[Laser3]

Thanks for your response.
1. I will look at change in lat/long format as an option.

2. Generally we keep the bottom mark as a fixed reference. The setcourse tool works on the bottom mark as reference (3 for triangle; 4 for trapezoid). To make adjustments all that is needed is the new lat/long for these marks => that can be provided by the boat that drops the mark using GPS or the tool's Geolocation button. This can be radioed to the other boats. All the course setters can adjust their setcourse tools for the change in the reference point providing a new set of bearings and lat/longs.

3. If the wind changes and the other Marks (1, 2, (3)) need to be moved, the setcourses tool can be adjusted by simply entering the new wind direction => revisedset of new bearings and lat/longs.
For regattas we have three boats for management. If the race officer (RO) decides there needs to be a course change for a Triangle course, due to a wind shift, he radios the new upwind bearing. All three boats adjust their setcourses tool settings. Boat1 moves the upwind mark using the new back bearing and RO checks the bearing => 'drop'. Boat2 moves the wing mark using the new bearings. RO and Boat1 check => 'drop'. We use bearings rather than lat/longs as we only have 2 GPS units (!!) and changing lat/longs is fiddly. Our RO generally relies on Boat1 and Boat2 to set the buoys, after announcing the new upwind bearing => delegation! In our experience mental arithmetic fails and causes endless confusion.

4. Setcourses has options for Triangle - starboard. Trapezoid starboard could be done if there is a need for it.

Cheers and Best Wishes

 

[dunedin]

Scottish National Sailing Centre at Cumbrae helped develop methods for setting positions for race marks, as well as other techniques, which was developed into a useful U.K. wide (and RYA?) mark Layers Course (used for some big events, poss including 2012 Olympics?)
Not attended so not fully familiar, but if your app is complementary to their techniques that sounds great. If duplicates then perhaps less so. Have you investigated this?

 

[Laser3]

Thanks for the feedback
I googled and found reference to RYA Mark layers courses. (2 days wow!). I could not find any reference to tools for getting bearings and lat/longs. If anyone knows of such tools that they use let me know (thanks).
This link summarises what is in the courses.
http://www.abclubhk.com/upload/Courses/Fact_Sheets/RYA-Mark-Laying-Courses.pdf

 

[Laser3]

I found this set of notes based on RYA course setter - Looks like they use tables for mark bearings! Great set of instructions. Cheers

see http://www.yotter.co.uk/Club Marklayer Course Notes.pdf

 

[Laser3]

Simple Ways to Estimate Distances Between Marks

Any ideas for simple ways to measure distances when laying marks?
=> Man-over-board can be used if you have a GPS
=> Golf range finders do not go far enough (<800m)
=> Binoculars exist with inbuilt compass and reticule but they are very expensive
Any other suggestions?

 

[Birdseye]

Re: Simple Ways to Estimate Distances Between Marks

you put the starting point into the gps as a waypoint and then at the potential mark you ask the gps the distance to the waypoint.

 

[lw395]

Re: Simple Ways to Estimate Distances Between Marks

Steam for n minutes at x knots....
Chartwork.
Vertical angle of a known height, e.g. a yacht mast.
Radar.

If we need to be accurate, we use GPS.

 

[lw395]

I was at a dinghy event recently.
No less than 5 mark laying boats, plus committee boat.
A good operation is all about getting a course in very quickly if needed, usually after a period of monitoring the wind.
Any technology used must be suitable for a 4m RIB laying marks in F6. i.e. it can be wetter than scuba diving.
Also comms frequently play up on such boats, even along fairly built up bits of coast.
Laminated tables of bearings are reliable technology. IP88 and no batteries required.

But peole need to use their judgement. All the formulaic stuff falls apart when the True Wind is different at each mark.

 

[scottie]

I was at a dinghy event recently.
No less than 5 mark laying boats, plus committee boat.
A good operation is all about getting a course in very quickly if needed, usually after a period of monitoring the wind.
Any technology used must be suitable for a 4m RIB laying marks in F6. i.e. it can be wetter than scuba diving.
Also comms frequently play up on such boats, even along fairly built up bits of coast.
Laminated tables of bearings are reliable technology. IP88 and no batteries required.

But peole need to use their judgement. All the formulaic stuff falls apart when the True Wind is different at each mark.

Having done the RYA marklayer course 10 years ago I would endorse Iw395 the minimum amount of data over VHF the better
It’s fine on a nice calm sunny day in 15ft of water but!
I have looked at the just three words apps which replaces lat & Lon figures with as it says jus three words and whilst introducing an extra element may solve a problem with communication

 

[Muddy32]

Having worked at both ends of the spectrum, I definitely work with the KISS principle.
The RO [often me] has discussed with the mark laying team the course configuration and angles before hand, and then they only need to "ping" the committee boat and be told verbally, often directly, as they are alongside what bearing and distance for the windward mark.
I then let them get on with it. They check with me that they seem to be in right position before laying the marks.

The two days needed for a mark laying course, involves a full day teaching how to use the GPS units, including a dry land, course setting exercise, and at least a day teaching about Alderney ring recovery system and anchor gear setups, followed by practical wet exercises including the various ways of setting and adjusting gates. It is not easy and demands both skill and practice, which is why I consider them to be true professionals at the end and leave them to it. They are part of the team.

We do not need Apps, just common sense and experience, which gives speed and flexibility.
The Olympic teams and many others were very good but in normal sailing, even National Championships, accuracy to the degree or metre is of little effect upon the clients/ competitors. A bit like target times really, how many folk are aware how long they were racing. Target times were introduced to coincide with TV ad breaks.

 

[Laser3]

Thanks I agree with KISS
We use these simple laminated dial devices to get bearings as a back-up for setcources.
To use these tools:
=> Print two copies of each and get them laminated
=> Cut out the centre disk from one copy
=> Pin or bolt it, carefully aligning it, so the inner disk can be rotated, but is held firm.
=> To use simply set the arrow to the Windward Direction and all the Bearings and Back-Bearings can be read.
=> The tool can be used for both Port and Starboard rounding courses

Protractor Tool 60-60-60 degree

and

Protractor Tool 45-90-45 degree courses

 

[StevieD]

I found this set of notes based on RYA course setter - Looks like they use tables for mark bearings! Great set of instructions. Cheers

see http://www.yotter.co.uk/Club Marklayer Course Notes.pdf

Yes that's robin Greys notes from Ballyholme in NI - I've worked with Robin and been through the course as laid out in the notes - he's very experienced and has lots of RO and Mark laying experience. As said a simple GPS to ping the CB, a distance and bearing for the windward mark a set of tables with a few other simple manual tools that work in the wet for calculating bearings from mark 1-2, 2-3, 3-4 and the inverse of, when hands etc are covered in sea water is ideal - the idea of a n app / tool is good but perhaps not in the heat of the moment!

 

[lw395]

Careful reading of the SI's is time well spent, it's not always the Committee Boat you want to ping.

 

[Muddy32]

Careful reading of the SI's is time well spent, it's not always the Committee Boat you want to ping.

The advantage of pinging the CB with yachts is that they, the competitors, normally ping us to get the start line on their plotters. So easy peasy for them to plot the windward mark. Dinghies however in a big fleet will probably have a leeward gate to round, hence the other reference point for the mark layers.

I did run the first mark laying course at WPNSA some 30 years ago, before hand held GPS was normal ,and it is a lot easier and accurate now, once that skill is mastered.

 

[Laser3]

One simple way to measure distances if GPS is not available is to use Golf drive distance devices such as CarryGolf for android. You click a start button and the tool gets your GPS location. Then down-the-track you click 'Distance' button and the device gets the GPS and calculated the distance. I checked with Google Maps and CarryGolf is quite accurate.

 

[Laser3]

I have completed DRAFT versions for DMM format.
see: https://www.setcourses.com/triangle_latlongDMM.html Triangle Lat Long DMM

& https://www.setcourses.com/trapezoid_latlongDMM.html Trapezoid Lat Long DMM

If you have time test them out. Thanks

John

 

[Laser3]

UPDATE => I have developed a MAP version draft.

It needs a Smartphone with GPS - which I don't have (!!) and so I need some one to give it a try and to provide some feedback

see https://www.setcourses.com/try.html

This tool provides a virtual GPS unit for Laying the Marks.
=> Enter the Lat Long for the Reference Location Mark 3 or click RefLoc to set it for your location.
=> Enter the windward direction and your preferences for the reach angle and leg length, Then Click GO.
=> This will display a map showing the Mark layout and their positions.
=>Then, to set a mark, proceed in its direction. Click the ShowMyLoc button to show your current position as a 'dot'. Click it again and your new position will be plotted. Click GO to clear the 'dots'
=> If you need to relocate the marks due a wind shift, without moving the bottom reference mark (Mark 3), then simply enter the new direction and the altered position of the marks will be displayed.>To change the reference, either enter its new location, or go there and click MyLoc to reset all the course marks.
=>Note: Click MyLoc and ShowMyLoc buttons twice for better accuracy
=> A Smartphone with GPS is required for accurate positions.

 

[Muddy32]

UPDATE => I have developed a MAP version draft.

It needs a Smartphone with GPS - which I don't have (!!) and so I need some one to give it a try and to provide some feedback


see https://www.setcourses.com/try.html

This tool provides a virtual GPS unit for Laying the Marks.
=> Enter the Lat Long for the Reference Location Mark 3 or click RefLoc to set it for your location.
=> Enter the windward direction and your preferences for the reach angle and leg length, Then Click GO.
=> This will display a map showing the Mark layout and their positions.
=>Then, to set a mark, proceed in its direction. Click the ShowMyLoc button to show your current position as a 'dot'. Click it again and your new position will be plotted. Click GO to clear the 'dots'
=> If you need to relocate the marks due a wind shift, without moving the bottom reference mark (Mark 3), then simply enter the new direction and the altered position of the marks will be displayed.>To change the reference, either enter its new location, or go there and click MyLoc to reset all the course marks.
=>Note: Click MyLoc and ShowMyLoc buttons twice for better accuracy
=> A Smartphone with GPS is required for accurate positions.

Regret that I have a life, and it is too short to bother.
If a change is needed, get on with it and make an educated guess to allow the competitors to be sailing rather than hanging around waiting for the mark layer to try to look at yet another gadget.