Gps waypoints mnemonics

Roberto

Roberto

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one of the winter projects is to input waypoints in a new gps, what kind of method do you use to choose the name/label to be given to each point ?

I only use gps with paper charts (no plotter), so with imray charts I thought of using the numbers associated by the chart to every single printed waypoint (ex. C29-42), but where two charts overlap there is a risk of confusion..
also, with other points not already marked in the chart, or other type of charts ?
permanently mark the chart with a numbered point ?
add names?

ideally, a method with some consistency, if possible I would try to avoid having a few waypoints labelled with the name of a nearby buoy, a few with numbers, another few with "leave to port while sailing towards XXX", etc

any thoughts ?
 
I generally set the waypoint to the position of significant bouys and lights, and then just name them by the place (e.g. ST_CTH for the actual position of St. Catherine's lighthouse or NEEDLE for the Needles fairway bouy). I'm not sure why you don't like this idea - much easier to remember and you are always going to be double checking on a chart - C29-42 doesn't seem much of a mnemonic to me!

I don't sail from waypoint to waypoint though - I enter them as the destination and then just monitor the distance and bearing to them.
 
I have the entertaining problem that while my garmin gps allows up to 6 characters for the name, when repeated on the raymarine displays, only 4 characters are shown - the last 4.

I give my waypoints 4-letter names and mark them on the chart. It has the benefit that I don't always have to refer to the chart when chhosing a waypoint e.g. I know PLYM will get me the entrance of plymouth sound whereas W123 would always need to be looked up.

I have a pile of chart folios with pre-marked numbered waypoints which is handy but always means looking them up.
 
Like you, I just have a simple [?] GPS and paper charts.

I started off trying to use abbreviations of the name of the place, buoy etc but 6 characters didn`t give enough scope. Then I bought "Waypoint Directory of the English Channel" by Peter Cumberlidge and tried to use the waypoint numbers from that. These consist of the page number followed by a two digit number. I soon found that the same waypoint can have up to four different numbers because it may appear on up to four different pages! My GPS can only store 200 waypoints so I soon ran out of memory.

Then I decided to use christian names for the waypoints e.g. Fred, Lucy. Pierre, Yvette etc; this works fairly well. The names are listed in a notebook and marked on any relevent chart. I had planned to use English names for UK waypoints and French names for French ones but couldn`t think of enough French names!
This "system" does have the advantage that you are forced to look at the chart to get the names of waypoints you need to use. So you can`t guess and perhaps make disastrous mistakes. Temporary waypoints are named something like TEMPnn.

It isn`t a perfect system by any means and I`d like to hear other peoples` ideas.
 
Just a general point. Whichever naming system you eventually decide on for your waypoints, make the waypoints yours, not those published in a widely available book. Imagine the scenario. Thick fog and everyone's heading for the same point!! Doesn't take rocket science to work out the consequences!
 
Depends how many charcters you van have for wpt names.

I check and double checkk and then worriedly check the wpts again with almanacs so i find it quite good to include (if appropriate) the page number of an alamanc for the re-checking. NEEDL427 for example. And of course gives you the page number to turn to from that wpt for going into unfamiliar port
 
Doesn`t take "rocket science" to offset the co-ordinates from the book a little on the safe side of the waypoint, just a little commonsense.
 
Glad it's not just me that has that trouble with the Raymarine repeaters. My GPS is a Furuno set but it still only hands over 4 of the 6 letters to the Sea Talk system. Wonder why that is.

On my set I get a six letter name and then a longer text field for a bit more description. For most places a six letter descriptive name is enough but if I forget what RYDEEN means I can look up the other field where it says Ryde Entrance. I back mine up to a spreadsheet every season then print them out and laminate them for future reference.
 
I happen to use precisely the system you suggest -- in my case C29-A, C29-B and so on, with this code plus lat and long marked in the margins. Part of my reasoning, and perhaps yours, is that Garmin's 6 digits aren't usually enough to allow an unambiguous label by other means. It only takes a little care to avoid duplications where a waypoint pops up twice in adjacent charts. And it's no big deal if it happens, anyway. If you're on passage from one chart to another, obviously you'll be looking at both in advance. The system has the advantage of clustering all adjacent waypoints together as you scroll through the GPS menu. The disadvantage, I suppose, is that many waypoints end up only being one digit different from each other, so particular care is needed when entering routes. But after plenty of use, I've found no reason to change the system.
 
My system is to name the waypoints as nnnAAA where nnn is a three digit acquisition number, which is used to select the waypoint on the GPS (as they are presented in sorted sequence) and AAA is a three character mnemonic (e.g. LHB for Lower Heads Buoy or PLO for Ploumanac'h Outer Approach). The Mnemonic gives a good clue that you are dealing with the right waypoint.

The waypoints are also entered in a database on my PC at home. Each entry comprises the nnn acquisition number, a location name (e.g. Chanel de Batz), a description of the waypoint (e.g. (Eastern Approach, Inner), latitude and longitude, any amplifying description needed (e.g. near Basse de Bloscon N-cardinal light buoy), the AAA mnemonic, and a route id, where used on the the GPS.

The database is sorted and printed twice for reference, first in nnn acquisition sequence, so that waypoints on the GPS can be easily identified on paper, and secondly in location name sequence so that when approaching the Chanel de Batz, say, all the relevant waypoints are grouped together for easy reference and selection. When sorting by location, the route id is used as a secondary sorting key, so that the waypoints are printed in route sequence, where applicable. My routes are intricate short ones rather than covering a whole passage.

It may sound like overkill, but the system has proved to be simple and reliable. The printed lists are bound with one of those plastic strips for ease of updating, with outer sheets of transparent plastic so as to be sprayproof in the cockpit.

New waypoints are pencilled in, keyed into the GPS, and then at leisure entered into the database to provide updated prints.
 
I always plot my waypoints on a paper chart before entering them on the gps.
If for instance I am going to Brighton from Dover I would plot the route on paper, then call the route "Dover-Brighton"
The waypoints are then plotted and called btn1, btn2, btn3 etc.
I mark these in pencil on my chart, so I know exactly where I am when I look at my charts. Routes are saved and used and re-used. but I always have my chart to hand and can check very quickly with a pair of legs to make sure I am where I think I am! If there is an important bouy I am going to pass I will enter a waypoint with the name of the bouy, but I never plot the exact position of the bouy, its always very well clear of the exact position. I never bouy hop! prefering to use my own waypoints all the time.

Barry
 
I prefer to enter the exact Lat/Long of the waypoint into the GPS then steer to miss by a suitable distance. I initially programmed them from the Reeds waypoint book which comes free with the almanac, then got myself confused by not knowing the actual offset when I needed them 'in anger'.

I don't follow what others are saying about only 6 characters, my Garmin 152 has 12 characters IIRC. So I name each one with an appreviated but meaningful version of the whatever is at the waypoint eg BEMBLDGE_ECM or NEEDLS_FWAY
 
Gosh!!

Having shared in the angst in this thread, I thank my lucky stars that I don't use waypoints.

About ten years ago my insurance premium for all-hours single-handed sailing virtually doubled - on enquiry it turned out that one of the broker's other clients had, with unerring accuracy, sailed to precisely his waypoint (I believe it was S Sunk Buoy). Not only did his boat sink but so did the buoy. The big cost for the underwriters was not the boat but Trinity House's consequential charges.

No, point-to-point navigation was something I vowed to eschew after seeing the results of a light aircraft navigating from radio-beacon to radio-beacon.

During the last 14 years I've used GPS the only waypoints I had in and used were the Dovey outer and the Bar buoy and naming them was a simple matter.
Decca, before that was just too inaccurate.
 
Re: Gps waypoints

With waypoints there are at least two major problems: inputting them correctly (and being able to check later); remembering what on earth the 6 characters refer to.
I dont use published waypoints for all the obvious reasons. I select and plot them on the relevant chart using the waypoint symbol, the lat and long and the name. That means I can go to the chart and check.
I only enter waypoints as part of a route. That means that the courses to and from a particular waypoint ought to give me warning when I make a mistake (and usually they do).
During the trip I record position when I remember - typically hourly and that gives a further check on the waypoints - also I try to look out of the window.
I do find that the GPS repeater on deck also helps. It tells you where you are and where you are going.
Some years ago I learnt to put a lot of waypoints in the approaches to the port as I had a nasty time going up to Treguier when the early morning mist rolled down.
I dont find writing waypoints down in a book useful. It's such a pain keeping the list in order. Currently I have about 300 in the Garmin and thats after a lot of weeding.
 
[ QUOTE ]
Thick fog and everyone's heading for the same point!! Doesn't take rocket science to work out the consequences!

[/ QUOTE ]

The assumed consequences are an urban myth. There are too many other variables.
 
Quite. Most boats I see out and about don't use auto systems, and are steering manually. Those that do have waypoints that match buoys seem to manage to miss them, and the rest have waypoints, like myself, that are mid channel, not on buoys, so I can take a personal decision as to exact track.


All a pile of bunkum depsite a very few high profile cases
 
It was a useful exercise, reading back the above account of my waypoint mnemonics: it soon dawned on me that I had not escaped completely from the numeric waypoint names forced upon me by my old Decca set.

Alphanumeric waypoint mnemonics in my system would be much better as LLLAAA, where LLL is a mnemonic for my location, and AAA is more or less as above.

Three advantages: the whole mnemonic gives a clue as to the location of the waypoint, only one paper print would be needed (in LLL, route id sequence), and the waypoints would be usefully grouped by location on the GPS.

After all these years...
 
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