Plotter essential?

Is a chart plotter essential/vital to your sailing?

  • I have a GPS

    Votes: 72 35.1%
  • I have a chart plotter

    Votes: 40 19.5%
  • I have both

    Votes: 113 55.1%
  • I have neither

    Votes: 5 2.4%
  • A GPS is a must have

    Votes: 63 30.7%
  • A GPS is a nice to have

    Votes: 73 35.6%
  • A chart plotter is a must have

    Votes: 30 14.6%
  • A chart plotter is a nice to have

    Votes: 114 55.6%
  • More than happy to sail without electronic nav gizmos

    Votes: 84 41.0%

  • Total voters
    205
A few years ago I was asked to help deliver a yacht somewhat early in the year and on asking about the on-board navigation facilities was informed there was no plotter, only paper charts and a GPS coordinates readout at the navigation station. As I was less than impressed I packed my notebook PC with a GPS USB adapter and OpenCPN with all relevant digital charts amongst my gear.

We had intended to make the passage in one stage but the first night brought 40 knot winds on the nose with sleeting rain so the decision was to close the coast and take shelter in an anchorage that I knew well.

It was an uncomfortable sail; there was no sprayhood and the waves hitting the bow were sheeting back in a constant deluge and the motion was extreme. The narrow entrance to the bay was always difficult to see even in daylight – on this dark night impossible, especially as the dim, port entrance light was not to see in the conditions.

I sat hunched in the companionway, out of the wind, rain and spray with the notebook on my lap, screen cursor on the entrance, continuously reeling off the range and bearing to the helmsman. Only when almost under the cliff was the port entrance light to see and we passed into calm water.

What I did would have been impossible with paper charts and traditional methods – even monumentally difficult with the existing, on-board system.

No, a plotter or its PC equivalence is not necessary, especially if you only go for local day sails. But as soon as a passage of any distance or time is involved it is crazy not to take advantage of what is available at very modest cost these days.
 
I sat hunched in the companionway, out of the wind, rain and spray with the notebook on my lap, screen cursor on the entrance, continuously reeling off the range and bearing to the helmsman. [...]

What I did would have been impossible with paper charts and traditional methods – even monumentally difficult with the existing, on-board system.

I agree it would have been difficult with log, lead, lookout, and trust-in-the-lord, but "monumentally difficult" with a GPS and paper charts? Come off it. Set a waypoint on the entrance and read off range and bearing just the same as you did with your laptop. And the GPS is waterproof against the rain and spray, too :)

(Not arguing that plotters let you do things in confined waters that would be difficult any other way, but this isn't a good example.)

Pete
 
I agree it would have been difficult with log, lead, lookout, and trust-in-the-lord, but "monumentally difficult" with a GPS and paper charts? Come off it. Set a waypoint on the entrance and read off range and bearing just the same as you did with your laptop. And the GPS is waterproof against the rain and spray, too :)

Okay, a touch of hyperbole involved, but easy to say without being there. Just hanging on below was not simple and wedging into the nav. table not an option. There was no waypoint possibility, only the lat. long. coordinates were supplied by the GPS receiver - a very old one; transferring them to the chart then plotting the bearing could never have been so continuous, which was very useful in the approach.
 
There was no waypoint possibility, only the lat. long. coordinates were supplied by the GPS receiver - a very old one

Fair enough then - I'd never heard of a GPS without waypoints. Even my dad's very early civilian GPS from the time of the Gulf War has this facility. Didn't the later Decca boxes do them? Seems odd that facilities would go backwards when GPS came in.

Pete
 
Fair enough then - I'd never heard of a GPS without waypoints. Even my dad's very early civilian GPS from the time of the Gulf War has this facility. Didn't the later Decca boxes do them? Seems odd that facilities would go backwards when GPS came in.
Pete
My Trimble Ensign did not have any waypoint facility. It was a prototype that I bought from a development company in Singapore while working there in ... about 1990.

The yacht in question had the GPS antenna/receiver delivering only the Lat. and Long. to a two-line digital display mounted over the chart table. I don't know the manufacturer but the owner was quite proud that he was traditionally using it and transcribing the coordinates to the paper chart. That night made him reconsider his installation - as well as installing a sprayhood.
 
Ditto my first Trimble just had a two line display for lat and long.

IIRC it cost about £700 pounds in the early nineties, which is the same as my current all bells and whistles SH plotter, some things do go down in price as they get better.
 
Ditto my first Trimble just had a two line display for lat and long.

IIRC it cost about £700 pounds in the early nineties, which is the same as my current all bells and whistles SH plotter, some things do go down in price as they get better.
I paid USD 950 for mine. It was a reject from a batch built for Trimble - the case was marked. I used it for many years until I got a Garmin GPS72 - goodness, what a leap in functionality.

Here is the only screen I remember the Trimble could manage.

trimble_loc1b.jpg
 
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I paid USD 950 for mine. It was a reject from a batch built for Trimble - the case was marked. I used it for many years until I got a Garmin GPS72 - goodness, what a leap in functionality.

Here is the only screen I remember the Trimble could manage.

trimble_loc1b.jpg

Good grief, you have a tall mast! :)
 
You are confusing chart accuracy with positioning accuracy - the positioning accuracy of Modern GPS (WAAS http://en.wikipedia.org/wiki/Wide_Area_Augmentation_System which is what my SH CP300 does) is better and more consistent than that used in the surveys that produced the information to create paper charts, ipso facto, the charts are wrong so when combined with a more accurate and consistent positioning system, there is an error.

Electronic charts are based on the same information as paper charts and are also augmented with more modern electronic data. Please read section "1420 Digital Chart Accuracy" in this MSI Document for a full explanation. All charts will improve with time now we have a much more accurate and consistent positioning system with which to do the surveys.

The world is going digital, and it will be better and more accurate than that which went before.

If anyone enjoys navigating with paper, pencil and compass then carry on. I certainly don't want to tell anyone how they should ensure the safety of their vessel.

What I can't support are the statements that modern, technology based systems are innacurate and should be second place to systems with so much room for human error. The fundamental problem being that paper charts were created from survey information based on less accurate positioning systems than we have available today.

We are now at the mature end of a transition from old to new navigation technology, the clock will not be turned back, but as always the responsibility lies with the skipper to recognise when something is not right and to come up with a backup plan.

I'm afraid I'm not confusing anything. I'm fully aware of the relative accuracies with GPS positions and charted positions. What I am talking about is incorrect information upon the chart. In my brief experience of Navionics I have hit a rock in Sweden, not because I thought I was somewhere else, but because the depth listed was three metres out. The 30 year old paper charts I had on board had the depth correctly marked. Also, last summer when helping to deliver a boat to Bangkok the skipper who knew the South China sea fairly well noticed that our proposed route was going to take us straight through a reef off southern Vietnam that wasn't on the Navionics charts. Cross checking with the PC based plotter (I forget which) showed that the PC version did have the correct information as did the paper charts we carried.

Now, two isolated examples (one in the arse end of the world) doesn't mean that the whole system is wrong, but it does show that they are not always correct and shouldn't be blindly relied upon. I accept your arguments about ECDIS and how with digital surveys charts are only going to get more accurate and reliable, but for the time being a lot of the electronic charts are copies of paper charts and occasionally information doesn't make the transition.

Personally I have a Laptop on board running SeaPro which has it's quirks but by and large is very good. It's still quicker and easier to pull information off a paper chart though, where you don't have to be constantly scrolling and zooming in and out.
 
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