Chart Plotters

[Hurricane]

Let me check if I got this right.
What you are saying is that if in a crossing there's some current pushing the boat to port first and to stbd later (or the other way round), the actual distance through water is shorter if you let the boat drift to port/stbd (or vv), rather than follow a straight COG, as any a/p would do on track mode, correct?

If so, I fully understand the principle, but I struggle with the 10Nm difference.
I mean, I had a look at my maps, and found that we're talking of an 80Nm or so crossing.
Therefore, it takes roughly a 40Nm drifting, to make the crossing 10Nm longer.
Now, let's consider a theoretical best case of current on one side for the first half, and exactly the same current on the opposite side for the second half - i.e., 20Nm drifting to port/stbd on the first half, and 20Nm to stbd/port on the second half, which is exactly what you need to reach the desired destination without "fighting the current".
BUT, at a typical P speed of 20Kts, it only takes 2 hours to make 40kts.
So, in order to drift sideways by 20Nm in the same timeframe, the current should be 10Kts, no less!

Btw, I'm well aware that the exact numbers are not so round, but I did the math by heart, without caring about trigonometry, just because your 10Nm made me curious. Unless there's some other major factor which I missed, these numbers should be good enough for a rough consistency check.

Back to the point, can that REALLY happen, in the Channel?
Is it possible to have not only 10Kts currents (which already sounds unbelievable, to my admittedly ignorant ears), but also flowing in the opposite directions half way, reversing the direction completely in the blink of an eye, during such a relatively short crossing?
That sounds like a nightmare even for ships!

I think Mark's comment carries more weight for sailing yachts where they can "lee bow" the tide thus getting more apparent wind etc.
But that isn't the case for motorboats and I tend to agree that Mark's point is a bit exaggerated.
Ant to do what he suggests require continual adjustment of the course - IMO not a good idea for beginners.

 

[Elessar]

Yes that's really true. A properly planned route eg from Southampton to ST Peter Port will be 10% (or more) shorter distance over water even at planing speeds - but I cheated a bit because it's a combination of allowing yourself to build up cross track error mid channel by steering a constant heading (on track the pilot will vary the heading to minimise XTE) and getting your timings right where the currents are favourable/adverse. It doesn't need a 10 knot current to to do this. The cross track current in the channel is a couple of knots tops. Pootling the difference is even more marked.
Next time i'm at the boat I'll do a needles to Cherboug comparison where the difference is solely the difference between Auto and Track modes at different speeds just out of interest

 

[BartW]

Modern Chart plotters,
What do you use on your chart plotter the most?
With all the new bits added, what do you like most or use the most on yours.?

ours is not that modern, I use it as a map, and gotoX,
also, use the radar regularly on night passages,
and not to forget as a video display
for the stern camera when reversing in to a berth,
or the anchor cam, when dropping and recovering the anchor.
or checking if everything ok in engine room

I have to admid, our boat has (from previous owners) all the paper charts from Italy and islands,
and I quite like to use them, not as intens as they teached me on the YM course,
but I like handling paper charts, and finding all the small details on the map

 

[Portofino]

Let me check if I got this right.
What you are saying is that if in a crossing there's some current pushing the boat to port first and to stbd later (or the other way round), the actual distance through water is shorter if you let the boat drift to port/stbd (or vv), rather than follow a straight COG, as any a/p would do on track mode, correct?

If so, I fully understand the principle, but I struggle with the 10Nm difference.
I mean, I had a look at my maps, and found that we're talking of an 80Nm or so crossing.
Therefore, it takes roughly a 40Nm drifting, to make the crossing 10Nm longer.
Now, let's consider a theoretical best case of current on one side for the first half, and exactly the same current on the opposite side for the second half - i.e., 20Nm drifting to port/stbd on the first half, and 20Nm to stbd/port on the second half, which is exactly what you need to reach the desired destination without "fighting the current".
BUT, at a typical P speed of 20Kts, it only takes 2 hours to make 40kts.
So, in order to drift sideways by 20Nm in the same timeframe, the current should be 10Kts, no less!

Btw, I'm well aware that the exact numbers are not so round, but I did the math by heart, without caring about trigonometry, just because your 10Nm made me curious. Unless there's some other major factor which I missed, these numbers should be good enough for a rough consistency check.

Back to the point, can that REALLY happen, in the Channel?
Is it possible to have not only 10Kts currents (which already sounds unbelievable, to my admittedly ignorant ears), but also flowing in the opposite directions half way, reversing the direction completely in the blink of an eye, during such a relatively short crossing?
That sounds like a nightmare even for ships!

It was a bit of a “ nightmare “ You needed to be flexible in terms of destination passage planning .

In a sailboat 4-6 knots out of Chichester or Poole harbour we set off once for Cherbourg and ended up in Aldeney , that’s about 20 miles W ( guess as 35 y ago )
Heading back to En , you were just grateful you hit the IOW even though you aimed at St Catherine point returning to Chi.

No plotter , no gps in those days and crossing shipping lanes in the dark .
Just paper charts , compass , and tide table books .We also had a hand held RDS thingy and a book on frequency and becon locations so every now and agian mid channel out of sight of land we would trianglate our position and mark it on the chart .FWIW ?

Also navigated across and around the N sea with same zero tech .

Always navigated around the Med with a plotter because every boats got one and paper .
I think you need a plan B like paper as well side by side .Thats partly why I,am not that interested in the lasted tech nav wise , because I grew up with out it and we managed fine .

 

[vas]

Thats not a fair comparison.
Those are faulty systems.
The paper chart equivalent of that is a pencil with no lead.

I wouldn't use a system like those above.
Instead, a simple iPhone (and I hate iPhones) with the Navinics app would be a good backup.
And if the problems with those two examples continue - FIX IT

+1000
heading sensor failed, pointless comparison from OP

 

[RupertW]

I think Mark's comment carries more weight for sailing yachts where they can "lee bow" the tide thus getting more apparent wind etc.
But that isn't the case for motorboats and I tend to agree that Mark's point is a bit exaggerated.
Ant to do what he suggests require continual adjustment of the course - IMO not a good idea for beginners.

Lee bowing can help a little for sailing boat but the effect of calculating the tides and not heading straight for the destination along a waypoint to waypoint line makes a huge difference at low speeds and carves hours off a channel crossing even under motor. So if your speed is 5 knots and the tide is going between 0 and 3 knots across your path then it makes a significant different to the number of miles you go through the water compared to sticking to a waypoint to waypoint line, but when the speed is considerably higher than the maximum tide then the effect is far less (without drawing the triangles of boat heading and tide cross you can picture a very narrow triangle for a boat at 25 knots compared to a broad one at 5 knots and sine 40 degrees shows a 64% effect compared to sine 10 degrees which is 17%).

So I myself wouldn't bother too much for a fast motor boat but you'd still lose sight of your competitor in a race across at the same speed. The way I'd picture it is that to keep on the straight line over the ground you firstly have to point left a few degrees - much more degrees if you are going slowly - to stay on the line then a few degrees right to stay on the line after the tide turns. If you had pointed straight at the destination at the beginning and kept to that compass course on the autohelm then the boat's track would be a big S curve to your destination and arrive early as you didn't try to fight the tide. Obviously the real trick is to calculate the amount you go left compared to right over the whole trip and set that initial compass course with that offset. Takes a few hours off a 5 knot boat's journey but maybe 10 minutes off a fast motor boat.

Edit:
Fancy chartplotter software used even on amateur sailing boats which race have both tidal and wind predictions built in so those calculations and options can all be displayed with the time to destination shown, provided you've fed it your likely speeds at different wind strengths and directions.

 

[powerskipper]

Things that can go wrong.
Card reader fail on the GPS. it will still give you a Lat and Long but no chart detail.
Heading not set up correctly on the display. Boat going north heading line going East.
Auto pilot not set up correctly. starts to do the wiggle as I call it, over steers one way the back other way, it can then loose the plot and turn its self off.
GPS position out by 40 meters, had my track running up on the land all the way up the Hamble river.
radar not fitted correctly and pointing 40 degrees of heading. Really spooking as you are trying to work out if chart out or Radar to start with, Overlays make for an interesting picture with this.
flux gate compass fail. that's what had happened to the GPS unit in the Video.
touch screen alinement out , and just a finger width, made trying to assess info on tide station or buoy interesting. .
there are other but those come to mind first.

But what they are great at ;
After you as a good boater has done a paper chart plan of your voyage , you can put it into the GPS , best as separate WP. then pull into route, there is normally an option on you set to use WP list or highlight the WP to add it to a route, you can then go the have a look at the bearing and distances and even see how long it will take you , it does not allow for tide , but if you run track when you leave, you can see, if you have been good and done a CTS, how well it work
If you put the WP in with a name and place them where they can be used in more than 1 route it keeps your screen clearer.
You can hide or show waypoints and routes.
You can place a WP on a danger and activate the go and it will tell you if you get close to it , if you use a WP arrival Alarm its great.
You can put info boxs on the screen to tell you how long/ time to destination if an active route or WP is in use , great for how long till we get there, or time for a cupper.

Radar MAPAR works well but need 10 mins to be accurate ,
AIS can have a delay in updating the boats position so do not use just that to make a judgement about a collision situation.
Doppler Radar is great we have just had it fitted on the School boat.
You can do Range bearing on radar and VRM distance of a danger area or shallow area. was great in the Orkneys last week.
There more stuff you can do. Its a great AID to navigation but there is something about seeing the whole area on a chart that is very reassuring.

 

[Hurricane]

Things that can go wrong.
Card reader fail on the GPS. it will still give you a Lat and Long but no chart detail.
Heading not set up correctly on the display. Boat going north heading line going East.
Auto pilot not set up correctly. starts to do the wiggle as I call it, over steers one way the back other way, it can then loose the plot and turn its self off.
GPS position out by 40 meters, had my track running up on the land all the way up the Hamble river.
radar not fitted correctly and pointing 40 degrees of heading. Really spooking as you are trying to work out if chart out or Radar to start with, Overlays make for an interesting picture with this.
flux gate compass fail. that's what had happened to the GPS unit in the Video.
touch screen alinement out , and just a finger width, made trying to assess info on tide station or buoy interesting. .
there are other but those come to mind first.

But what they are great at ;
After you as a good boater has done a paper chart plan of your voyage , you can put it into the GPS , best as separate WP. then pull into route, there is normally an option on you set to use WP list or highlight the WP to add it to a route, you can then go the have a look at the bearing and distances and even see how long it will take you , it does not allow for tide , but if you run track when you leave, you can see, if you have been good and done a CTS, how well it work
If you put the WP in with a name and place them where they can be used in more than 1 route it keeps your screen clearer.
You can hide or show waypoints and routes.
You can place a WP on a danger and activate the go and it will tell you if you get close to it , if you use a WP arrival Alarm its great.
You can put info boxs on the screen to tell you how long/ time to destination if an active route or WP is in use , great for how long till we get there, or time for a cupper.

Radar MAPAR works well but need 10 mins to be accurate ,
AIS can have a delay in updating the boats position so do not use just that to make a judgement about a collision situation.
Doppler Radar is great we have just had it fitted on the School boat.
You can do Range bearing on radar and VRM distance of a danger area or shallow area. was great in the Orkneys last week.
There more stuff you can do. Its a great AID to navigation but there is something about seeing the whole area on a chart that is very reassuring.

Julie, please don't take this conversation the wrong way.
My views are just posted as an intellectual constructive discussion.
Although I hold strong views about this stuff, I am not trying to post nasty replies.

All the above things that you have mentioned in your first paragraph are failures in the equipment.
Apart from the auto pilot, I have never had any of those issues and I'm not sure that plotting on paper charts would make any difference.
I leave my auto pilot set to defaults and the "wiggle" as you put it is corrected when I set my response level.
This isn't a failure or a problem - the autopilot is working the way it was designed - I happen to have mine set as though it was a sailing yacht - changing the response to a setting for a motorboat stops the "wiggle".

Your second paragraph
WOW
I wonder how many people do as you are saying.
Especially when it is SO easy to use the electronic plotter with a Go To Cursor.
Actually, your point about entering waypoints (IMO) creates a huge navigation risk.
How many people have entered a Lat/Long into a plotter and got it wrong?
It is incredibly easy to transpose numbers when you are setting up waypoints - and plotters like Raymarine don't make it easy.
Anyway, my big point is please get students using Go To Cursor ahead of plotting on paper charts.
As I say, Go To Cursor is easy and safer.

If you must pre-plan passages (say at home) it is much safer to (again) do it electronically on a Laptop PC and uploading the passage to the plotter.
That way, there will be no errors in waypoint lat/long.
I was doing this 15 years ago with my old Pathfinder plotters.
Then with a cheap GPS attached to the Laptop PC on board, you can monitor the boat's progress on both the plotter and the PC.
I do this all the time but, then again, my system is set up to do this stuff.
All your stuff about placing a waypoint on a danger and enabling a waypoint arrival alarm is far too complicated.
Just look at a plotter's screen and steer away from the dangers.
As you say, info boxes are good but you set them up once and leave them - I haven't changed ours in 10 years.

Now, I strongly disagree with your comments on MARPA vs AIS.
Maybe it is because AIS is the "new kid on the block" but IMHO, AIS is far superior to MARPA.
The range is better and your comment about not updating often only applies to Class B.
Class A (shipping) transmits within 3 minutes - you should never be that close.
So, compare MARPA to AIS
MARPA can also be more complicated - especially when using it on a radar only display using relative vectors.
Using MARPA, CPA can be very inaccurate as it is very dependant on having a very accurate electronic ships compass (fluxgate etc).
OTOH AIS receives the other ships bridge systems - even data on the other ships helm can be transmitted.
We are also now seeing more and more fixed AIS transmissions - remember, the AIS target doesn't need to actually be at the location that it is showing.
This means that coastguard authorities can place an AIS target without leaving the comfort of their offices.
Lights are now springing up everywhere with an AIS "beacons"

For me it is AIS anytime ahead of radar.

I'm a but confused about your comment on Doppler Radar.
I know that angular measurement using radar is very inaccurate but I thought that ALL radar is very accurate when using it to calculate distance.
So (if you must), you can fix your position using radar by taking distance bearings instead of angular bearings.
But, this is my point WHY?????
GPS systems are so cheap and they are everywhere.
Why make things so complicated?
When we go to sea in our boat, we have the main ships GPS, the AIS's GPS, a GPS feed to the ship's PC - my phone has a GPS running Navionics - like my phone, my tablet runs Navionics and OpenCPN.
All this stuff positions you far more accurately than you can on most paper charts - AND INSTANTLY

You are just making everything far too complicated.

Sorry - rant over.

 

[Newbroom]

Sorry Hurricane
I come down on the side of Power Skipper. I always plan my route on paper charts and after entering it in the chart plotter compare the Distance and bearing with my own plot. The CTS can only be made accurately after tidal calculations are made. Using the track facility will see you using great mileage than if you work out a CTS taking into accounts tidal streams. In areas of strong tidal streams over short distances using just track can get the unwary into dangerous areas why seemingly following a direct course for a distant waypoint.
How many people realise that they shouldn't use track function when crossing a TSS because the shortest distance is a compass course at right angles to the TSS.
We could argue this for hours but I think so long as there is an understanding of the benefits and shortfalls of electronic navigation backed up by a understanding of the basics of navigation neither of will win the argument

Dave

 

[Hurricane]

Sorry Hurricane
I come down on the side of Power Skipper. I always plan my route on paper charts and after entering it in the chart plotter compare the Distance and bearing with my own plot. The CTS can only be made accurately after tidal calculations are made. Using the track facility will see you using great mileage than if you work out a CTS taking into accounts tidal streams. In areas of strong tidal streams over short distances using just track can get the unwary into dangerous areas why seemingly following a direct course for a distant waypoint.
How many people realise that they shouldn't use track function when crossing a TSS because the shortest distance is a compass course at right angles to the TSS.
We could argue this for hours but I think so long as there is an understanding of the benefits and shortfalls of electronic navigation backed up by a understanding of the basics of navigation neither of will win the argument

Dave

Thanks for your reply.
I suspect that you are in the minority.
You don't say where you cruise but, maybe a trip out into the Med would convince you that people who do this a lot - just don't do what you are saying.
Yes, we have a plan and, yes it involves paper charts, but it is all about simplicity.
It isn't just the Med - before moving to the Med, we did a lot of cruising up and down the English Channel.
I have met a lot of boaters in my time.
Very few plot their courses the way you say.
That doesn't mean that they don't use paper charts - but it does mean that they make the job easy by using the electronics.
And I'm sure that very very few use CTS apart from whatever the autopilot/Go To Cursor offers.

 

[Elessar]

Sorry Hurricane
I come down on the side of Power Skipper. I always plan my route on paper charts and after entering it in the chart plotter compare the Distance and bearing with my own plot. The CTS can only be made accurately after tidal calculations are made. Using the track facility will see you using great mileage than if you work out a CTS taking into accounts tidal streams. In areas of strong tidal streams over short distances using just track can get the unwary into dangerous areas why seemingly following a direct course for a distant waypoint.
How many people realise that they shouldn't use track function when crossing a TSS because the shortest distance is a compass course at right angles to the TSS.
We could argue this for hours but I think so long as there is an understanding of the benefits and shortfalls of electronic navigation backed up by a understanding of the basics of navigation neither of will win the argument

Dave

Really? Always? Despite being the one who called Mike on this I’m far nearer to his camp on this! The only thing I disagreed with was his suggestion to not teach paper at all.

I almost always use Mike’s track to waypoint approach and my charts stay in the drawer. I only plot on paper first if my route involves a significant change in tidal flow on passage. Which in practice means holidays.

The only other times I get them out are for the occasional practice without GPS or when I have guests onboard so I can show them the area. Or when I’m teaching......

They are there if all the GPSs fail of course but that’s never happened.

 

[Newbroom]

Thanks for your reply.
I suspect that you are in the minority.
You don't say where you cruise but, maybe a trip out into the Med would convince you that people who do this a lot - just don't do what you are saying.
Yes, we have a plan and, yes it involves paper charts, but it is all about simplicity.
It isn't just the Med - before moving to the Med, we did a lot of cruising up and down the English Channel.
I have met a lot of boaters in my time.
Very few plot their courses the way you say.
That doesn't mean that they don't use paper charts - but it does mean that they make the job easy by using the electronics.
And I'm sure that very very few use CTS apart from whatever the autopilot/Go To Cursor offers.

Each to there own I suppose. I started boating with a DF and an echo sounder then was delighted with Decca when it appeared and remeber paying over a £1000 for Phillips Decca navigator in about 1983 and then had very early GPS with which you could wait up to an hour to get a fix.
Boated in the med and done about 18 trips across the bay of Biscay only ever used auto to come across the bay never track.
Still stuck in how I started and just use nav aids as nav aids and not as my primary source of navigation. I don't think either of us are totally wrong
Dave

 

[MapisM]

You are just making everything far too complicated.

Positively +1.
Sometimes I have a funny feeling that we get carried away by the technicalities here in the asylum, and we forget that it's all about boating for pleasure.
Onboard electronics are probably the best example of onboard equipment prone to trigger the keeping up with the Joneses syndrome, in pleasure boaters.
Otoh, the much less sophisticated gadgets that on average can be found on commercial boats don't seem to restrict them from being out there 24/7, sometimes in conditions when most if not all of us wouldn't even dream of leaving our berths...

 

[MrB]

I read this and think of aviation. I think boating is about 10-15 years behind aviation with regards to analog/electronics. I remember learning to fly with charts, analoge VOR's, DME's etc, just doesn't happen now, it's all electronic moving maps etc. Embrace technology and the simplicity of it all. I'm with Hurricane and having a redundancy of backup systems is dirt cheap now so it's a no brainer. Charts are nice though. :encouragement:

 

[Newbroom]

I read this and think of aviation. I think boating is about 10-15 years behind aviation with regards to analog/electronics. I remember learning to fly with charts, analoge VOR's, DME's etc, just doesn't happen now, it's all electronic moving maps etc. Embrace technology and the simplicity of it all. I'm with Hurricane and having a redundancy of backup systems is dirt cheap now so it's a no brainer. Charts are nice though. :encouragement:

PPIs still have to learn with charts and traditional navigation or at least still did a couple of years ago. The biggest difference between light plane navigation and marine navigation is you have to have a plan in advance. CTS being crucial to safety,VOR DME is still taught Non precision approaches still done with RDF ie NDBs and VORs. and still used.

 

[Elessar]

I read this and think of aviation. I think boating is about 10-15 years behind aviation with regards to analog/electronics. I remember learning to fly with charts, analoge VOR's, DME's etc, just doesn't happen now, it's all electronic moving maps etc. Embrace technology and the simplicity of it all. I'm with Hurricane and having a redundancy of backup systems is dirt cheap now so it's a no brainer. Charts are nice though. :encouragement:

OK Powerskipper you seem to have started something akin to a WAFI anchor thread.

The next big question is.............

North up, head up or course up? (north up being correct of course and everyone else being - well - wrong because there can be only one way of doing things )

 

[powerskipper]

Can I just say a few things, there is nothing wrong with what you are doing but for some it would not work as well.

All the above things that you have mentioned in your first paragraph are failures in the equipment.
If your new to boating or have never seen equipment fail you would not know it was wrong, an auto pilot not set up will do the wiggle as it can get a conflict of info, ie, heading bearing miss aliened and gps input for heading different.



I
Especially when it is SO easy to use the electronic plotter with a Go To Cursor.
Goto works by drawing a strait line from where you are to the point you want to go to . fine if you have checked that line for shallow water, land , hazards .

Actually, your point about entering waypoints (IMO) creates a huge navigation risk.
How many people have entered a Lat/Long into a plotter and got it wrong?
That's My point, by doing the paper then into chart plotter, you are checking your own navigation , its easy to get it wrong. but you can work out why and correct it .Practise make you better. why I think this is important .
1. if you hear a Lat and Long given over the VHF for say a Mayday, a hazard, exclusion zone and you then plot the position on your chart , but get it in the wrong position on the chart, you could get yourself into trouble.

2 WP are give as Lat and Long in the almanac for a point of a harbour as an arrival point. If you want to put this on a chart to plan a passage to that point you need to get it right.



If you must pre-plan passages (say at home) it is much safer to (again) do it electronically on a Laptop PC and uploading the passage to the plotter.
Yes its a great way but the nature of electronic charts is a zoom view. so detail is lost as you zoom out. so for total safety, if you planning it that way you must go over the whole route on fullish zoom to check for hazards . if planned on a chart of right scale its all there to see.
All your stuff about placing a waypoint on a danger and enabling a waypoint arrival alarm is far too complicated.
Just look at a plotter's screen and steer away from the dangers.
its very simple, if say there is only one rock in the area you want to play just use your go to button.
AIS
The key factors that affect the overall frequency of the transmitted AIS information are the type of the AIS transponder (Class A or B) and the moving status of the subject vessel, as shown in the following table.
Transponder Type
Vessel's Moving Status (Transponder ON)
AIS Transmission Rate
Class A
Anchored / Moored
Every 3 Minutes
Class A
Sailing 0-14 knots
Every 10 Seconds
Class A
Sailing 14-23 knots
Every 6 Seconds
Class A
Sailing 0-14 knots and changing course
Every 3.33 Seconds
Class A
Sailing 14-23 knots and changing course
Every 2 Seconds
Class A
Sailing faster than 23 knots
Every 2 Seconds
Class A
Sailing faster than 23 knots and changing course
Every 2 Seconds
Class B
Stopped or sailing up to 2 knots
Every 3 Minutes
Class B
Sailing faster than 2 knots
Every 30 Seconds
this is the scary bit.
To ensure fast handling, accurate depiction and effective management of the incoming information, MarineTraffic uses proprietary downsampling techniques that take all of the above-mentioned factors into account. As a rule of thumb, in-range vessels will be updated on a 60-second basis (1 position report per MMSI per minute).
from here
https://help.marinetraffic.com/hc/e...-of-the-vessels-get-updated-on-MarineTraffic-


Now, I strongly disagree with your comments on MARPA vs AIS.
Maybe it is because AIS is the "new kid on the block" but IMHO, AIS is far superior to MARPA.
The range is better and your comment about not updating often only applies to Class B.
Class A (shipping) transmits within 3 minutes - you should never be that close.
So, compare MARPA to AIS

We are also now seeing more and more fixed AIS transmissions - remember, the AIS target doesn't need to actually be at the location that it is showing.
This means that coastguard authorities can place an AIS target without leaving the comfort of their offices.
Lights are now springing up everywhere with an AIS "beacons"
Yes they have one on Calshot spite and it had the wrong picture on so I emailed them and told them and sent them a correct picture.




I know that angular measurement using radar is very inaccurate but I thought that ALL radar is very accurate when using it to calculate distance.
So (if you must), you can fix your position using radar by taking distance bearings instead of angular bearings.
But, this is my point WHY?????

if you are going though a narrow estuary that has a channel more to one side than the other and a dog leg , you can set up the VRM so you have a better chance of keeping yourself where you need to be


All this stuff positions you far more accurately than you can on most paper charts - AND INSTANTLY

You are just making everything far too complicated.
Its fun, a GPS is to me a confirmation of where I think I am on the chart. and you only need to plan on paper a passage once and then put it into the GPS, you can then run it , change bits if not happy with bits of it. job done,

 

[powerskipper]

Well I try my best to entertain . good debate. xx

 

[Hurricane]

Well I try my best to entertain . good debate. xx

Yes - good debate - thanks for starting it.
I always find it refreshing to have discussions with people who disagree and remain friends.
Agreeing to disagree is very important.
And if you respect other people's views you can often learn that you are wrong sometimes.
I'm not drawing conclusions to who is wrong and right in this case though.

 

[Elessar]

Well I try my best to entertain . good debate. xx

+1 to that