Using waypoints / autopilot

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PD4U
If you have room for a laptop, you can get a large enough image to plot your whole course on the screen, then zoom in and reposition the waypoints as needed.
Without knowing the kind of plotter you are using, we are all guessing, trying to fit your question to our own experience.
I use a laptop, recently renewed with a larger screen, 18" corner to corner, so the whole route method works for me. I also have a 5" plotter that lives up on the FB and goes in the dinghy. Both of those locations lend themselves to VFR, so I don't often want to plot a route. When I do, I feel your pain.
When following a route electronically, the AP does go by the most direct route. When just setting the AP and following the route visually, with corrections as the XTE grows, the route traveled is not as efficient, but WAY better than not using the AP.
 
I'd venture that if you are auto-navigating to a waypoint using a chartplotter / autopilot purchased within the last 10 years then you are likely following a great circle route.

My Furuno Navnet has the option of Great Circle or Rhumb.

Rhumb lines

A ‘rhumb line’ (or loxodrome) is a path of constant bearing, which crosses all meridians at the same angle.

Sailors used to (and sometimes still) navigate along rhumb lines since it is easier to follow a constant compass bearing than to be continually adjusting the bearing, as is needed to follow a great circle. Rhumb lines are straight lines on a Mercator Projection map (also helpful for navigation).

Rhumb lines are generally longer than great-circle (orthodrome) routes. For instance, London to New York is 4% longer along a rhumb line than along a great circle – important for aviation fuel, but not particularly to sailing vessels. New York to Beijing – close to the most extreme example possible (though not sailable!) – is 30% longer along a rhumb line. (excerpt from Calculate distance and bearing between two Latitude/Longitude points using haversine formula in JavaScript)
 
Petdoc4u
It would help to answer your question to know what electronics you are using.
I have two 16" touch screens at the helm, a MS Surface running Coastal Explorer and an iPad with the Garmin app on it. I can plot routes on all of them.
I actually plot our daily route on the iPad and it shows the boat riding along it all day. The ipad is very easy to create a route on, but I do not use it to "drive" the boat via autopilot.
On the helm plotter, one screen is zoomed in at .5 mile and one screen is at 2 miles or 10 miles, with radar overlay.
I have several tracks north/south on ICW so I can usually just follow a prior track. A quarter mile one way or the other is not going to make me fret about fuel or anything.
Cheers,
 
Do you have your auto pilot linked to your GPS?. If so your GPS probably has off-line route planning and plotting where you can prepare in more detail while you are at the dock and spend the time you need focusing on it.
Similar to the laptop idea mentioned above.
 
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I'm old school

I like to work w a paper chart to plan a course and pick waypoints that make visual sense...
by that I mean ones I can check and confirm visuslly while underway...

I do have a PC based program and do the "work" at home and upload on the boat.
I finding the advanced planning a fun part of taking a trip.

eg... Always abeam of a nav aide...on a heading towards a stack or water tower or light house etc

For the above you obviously need to see the big picture.
For routes I will reuse I record them in a section of my log and include
WP ID, True & Mag heading & distance (SM & NM) to next WP
If interested let me know and I can send you an example.

If you have a local Sail & Power Squadron nearby they offer two piloting courses that include chart & GPS plotter use...two of their most interesting IMHO
 
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The advantage of using routes created by placing Way Points is that you become more familiar with you planned route before you just Wing It. The second and most important reason to use routes to travel common places is to obtain a high level of confidence in your proven lane of travel. So when the sun falls or the weather turns into a white out you can spend your time looking for other boats and obstacles, instead of hoping your not about to run aground. Especially if circumstances have you out at night and you are exhausted.
 
...I have not yet mastered the technique or secret to plotting a course which is practical. Typically I find my waypoint miles off shore which if followed would result in wasted time and fuel. Zooming in to place each waypoint is a challenge as the big picture is lost. Is there a way to plot waypoints effectively? or does everyone deal with this?

When I place waypoints on the chartplotter I am never able to place them where I would like to go. Perhaps it just takes practice in waypoint plotting to get the desired route.


As others have said, and you've mentioned in passing... zooming is part of the answer. Placing waypoints contextually first (zoomed out) and then more precisely (zoomed in, drag the waypoint if necessary) can work relatively easily.

But then once you've connected all those waypoints into a route, I can also recommend you actually "fly" your resultant route in advance while zoomed in... so you can be sure you're not going to run over a rock or whatever that's not visible when zoomed out.

-Chris
 
Thank you to everyone for your input. Various perspectives allow us all to expand our understanding of interfacing electronics with cartography to facilitate getting from A to B safely and efficiently. I use a 14" Raymarine MFD with Navionics Platinum chip. I have no complaints about the hard or software other than the time it takes to plot a course. Garmin has an autoplot feature which I have heard good things about.
Cheers,
-David
 
The zooming in should get easier with practice.
Take the time to zoom in close to set up your waypoint accurately, and give it a name that will help you remember what it is.
Then on later trips when you want to use that waypoint again, just select it from the waypoint list rather than the map.
I have hundreds of waypoints on my local grounds, have to hide them to see the map!
 
Garmin has an autoplot feature which I have heard good things about.

I have a Garmin that does that. I use it, but with a LOT of skepticism.

First, it doesn't always work. If the route is too complicated, it won't even try.

Second, it isn't always safe. It's been known to plot a course over dry land. But more often, it chooses really "stupid" courses, like finding that tiny stretch of 4' deep water among big rock piles. Theoretically possible, but what if there are 2' seas (and 2' troughs) in that 4' area? If you set the minimum depth too deep to compensate, it'll totally bypass areas that ARE safe.

Third, it does stupid things. Like going miles out of the way when there's a clear channel to where you want to go. No clue why sometimes it seems overly cautious, and other times reckless.

That said, it's an interesting technology that will no doubt get better with time. And every once in a while, it chooses a decent course that you can follow with minimal modification.

Unfortunately, Garmin (like most manufacturers) has no interest in updating the device you bought last year. All their efforts are directed at next year's model. So I don't expect to see those improvements.
 

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