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Sailing with instruments
The way I see it a MFD/GPS plotter is the key interface. They come with built in GPS... and you can connect, radome, speed log, depth sounder, wind speed/direction masthead transducer, water temp, AIS. You can link to a VHF for DSC calling. You can drive some APs from some MFPs. You can add 4x4 dash displays for numeric date..BS, TWS, AWA, AWS and so on. Dash displays are easy to read from anywhere in the cockpit (usually)

You should have a MFD plotter where you steer the boat from (binnacle mounted in most cases) or readable from wherever you are steering from. You can add a 2nd MFD below decks to display charts, AIS, position, and all numeric data.

Apparently sailors are now using standard laptops these days for navigation... The wisdom of this eludes me... not suited for the marine environment... difficult to mount/secure. Tablets may be a bit better and a smart phone even better... but the displays are small.

Personally I want 4x4 dash displays for speed, depth and wind data.... and a plotter to see where I am on a chart... which can have AIS and even weather overlays as well as RADAR. I find Navionics on a smart phone does the job. I don't bother with routes and enter a single way point as needed for heading info. The course and heading lines and tracks on a plotter are the most useful features.

I only have two hands and two eyes to do all sailing functions,
 

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Concerning autopilots.

I believe most newer autopilots will interface with a GPS plotter and steer to a waypoint. But can those APs simply be set to steer a magnetic course?

One of the hassles of driving the boat manually at the helm is boredom and the other is fatigue. AP solves that problem perfectly. A helmsman usually steers a magnetic course... to "a fixed point" such as a buoy or land feature... or a magnetic course (using the binnacle compass)... or to the wind to keep the tell tails flowing. When steering a magnetic course or aiming to a fixed point one often has to trim the sails as the wind direction and or strength changes. Of course motoring essentially "ignores" the wind most of the time. However it may make sense to consider the wave action. There are APs which can sail to a wind angle... but that may not get you to the mark you want. Long story short... sailing with an AP is / can be a dynamic process. Motoring to a point is hardly dynamic. GPS driven AP will "consider"... set and drift'' leeway and current... always pointing the boat and steering to a GPS set point. As it does, crew will trim the sails accordingly. Sailing with an AP requires the crew to trim (usually) to maximize boat speed/velocity to destination.

Are sailors using AP these days mostly sailing to a fixed GPS determined location? Or are they sailing a magnetic course? Or are they sailing to a set wind angle?

My AP does not accept GPS waypoints or sail to a wind angle.... it sails to a "set course". It's like having a helmsman that you tell... sail 230 magnetic... and they do it. Someone (me) trims the sails. You tack or jibe by setting the new course, and dealing with the sail trim. I find the AP tremendously helpful. I often set a waypoint which I can see on the chart plotter and data about the waypoint on dash displays...DTW, TTG, CTW, VTD and so on. I will do a combination or tweaking the course heading and trimming the sails. What I don't have to do it be stuck at the helm.. YEAH! I digest the data from the instruments and select the course to steer... observe (watch keeping) and do various things... like make a cup of coffee.

Are you using your AP to steer to a fixed coordinate (waypoint) or to a magnetic course (to a waypoint or mark/feature of the land etc.? Do you rely on tell tales, a windex or wind data on instruments when sailing with the AP?
 

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Yes, that is the most basic level functionality that all of them share. All autopilots are standalone, and interfacing them just provides extra functionality.



All of the above.

AP to compass: used mostly when we just want to push a button to keep a straight course while we fiddle with something. Often used while entering/leaving an anchorage and getting things out/away before setting on a determined course.

AP to waypoint or course (pretty much the same thing): used a lot while actually sailing. Like you mention, one needs to trim sails accordingly while in use.

AP to wind: mostly used when beating or running because sails don't need to be trimmed and it prevents unintentional jibing or going in irons on wind shifts. Also often used when raising sails to keep the boat headed into the wind in an anchorage where the wind is usually shifty.

We rely on telltales to help with sail trim. Have a windex and wind instrument that are used to make navigation decisions - our favorite instrument setup is to have one instrument displaying the traditional wind rose with AWD and TWD along with instantaneous wind speeds, and another displaying a timeplot histogram of TWD and TWS. The latter gives us a good feel for changing wind conditions and whether they are temporary or truly changing.

Mark
Your instruments are more sophisticated (newer) than mine. All of mine are from the 80s. I added an MFD with radar and an AP in the late 80s. Last purchase was a Zeus T7 which has on board GP and I use in a coach roof winch. And newer is Navionics on my smart phone.
My dash displays Depth, Boat Speed, Analog Apparent Wind direction (relative to boat) Apparent Wind Speed... then I have a display I can select to display: True wind speed, true wind angle, COG, SOG, DTW, CTW, TTG. I usually toggle between SOG and COG. I check the dash displays data frequently. I steer a course with the AP which does not interface to GPS. I usually steer heading the boat to a point on the plotter... plotter shows a heading line to infinity. When I steer with the heading line I don't bother with the actual numeric heading. I can also see if that heading takes me over thin water etc. The entered waypoint will simply give me an idea of when I will arrive... not that I can do anything about it. I find using the plotter's heading line is all I need for "on the fly" navigation... I don't do route planning.

++++

If got a new API would likely not use the navigate to waypoint much... continuing to use the plotter and steer with the heading line. I recall trying to help newbies steer the boat... Often I would tell them to steer aiming the boat to the red house... they always had problems steering to the binnacle compass. Steering with a heading line is the analog to steering to the red house.
 

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these are excellent questions..

I run almost exclusively to compass course.. quite simply because i may be tacking.. kind of hard to tack if your GPS is calling the shots.. also.. i am often dodging things.. crab pots, other boats.. buoys.. again.. GPS cannot provide me this functionality..

I mostly run to flux while in the rivers and ICW because course corrections need to be made due to different buoy locations.. same with coming into or exiting inlets..

I sometimes will run to wind.. but rarely..

Running a 200 or 300 mile run, winds will often change causing me to change course to get a more favorable speed. As a result of these issues.. i rarely run the auto pilot with the GPS.. on the other had, i am always following a course on the GPS.. even if i am tacking back and forth across it..

Since Raymarine comes with a flux compass.. more than likely this owners boat did not need a connection to the 2k compass.. So he could probably disconnect and run to compass.

Probably the best investment I made was replacing the old Raymarine 4000 iirc.. with a new Raymarine Evo.. the 9 axis accelerometer sensor has the autopilot turning the rudder as the boat slews through waves even prior to being off course.. it reacts like a human pilot..
My AP only steers to a compass direction and has it's own fluxgate compass. You see the course with a large round dial with degree markings... it's like a tiny helm. The APs electronics can limit yawing and the responsiveness... making small corrections. It's very intuitive to use. And pretty much like having someone at the helm. My AP controls are ergonomically and conveniently located where I can see and access my cockpit plotter, dash instruments, engine controls as well as the main and head sail sheet winches. I can AP steer from a protect location with excellent visibility. To tack I make a large course change of 100-120 degrees and adjust as I see the wind and seas and to jibe I slowly turn to dead down wind.... jib the main and head sail and slowly turn to the new down wind course. Its algorithm adjust to sea state supposedly.
So as I said...and I repeat... I set the compass course based on what I see...with the heading line on the plotter. Rather than set a coordinate for a waypoint.. I turn the AP dial so that the heading line on my plotter(s) intersect the location I want to get to. This often means trimming as one does when manually holding a course.
I see no advantage to the capability to steer to a coordinate. I am still very much involved in all sailing decisions... steering, trim, and watch keeping.
 

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For example, motoring - particularly in a cross current. Yes, one can sit at the AP continually adjusting the course to meet a waypoint, but it is much easier to just set the AP to that waypoint and relax.

Your description of setting the heading line on the plotter to meet the COG to a waypoint is exactly setting the AP to the waypoint. I don't see much advantage of doing this manually (and continually making adjustment), and both ways require one to adjust sails and stay on watch. You might think you are active in the steering, but allowing an AP to partially steer is a strange line to draw between full AP steering vs. full hand steering.

One advantage of steering to a waypoint/route vs only to a compass is making a course change short handed. When steering to a waypoint, and that waypoint has been reached and the boat needs to go to the next, the AP alarms that it wants to turn to the next waypoint and one pushes the "OK" button, then one is free to adjust sails while the AP turns and locks onto the new course. No juggling tasks between setting the course and adjusting the sails.

Another advantage of having the ability to integrate a GPS (regardless of if it is used) is if the compass goes down, the AP can use COG as heading and continue to work. Otherwise, one has lost their AP.

Having wind integration opens up much more functionality and usefulness.

Mark
I observe the track which will deviate from a straight course because of current and making leeway for example. But I can find the course which essentially steers the direct line... and yes over time I AM making some minor course corrections. I do this when sailing or trim... Sailing is an ACTIVE process.
Also key to how I navigate/steer with the AP is I see where the heading will take me... over hazards, thin water and so on. The GPS waypoint doesn't know what its course passes over.
I think the KEY word is that I am ACTIVE with respect to steering evaluating the chart and weather/sea conditions constantly and accounting for them. But the level of activity is minor... If there is a cross current in a few minutes I can see how the set course needs to be corrected... And observe is KEY... I need to consider traffic and make adjustments accordingly. A set waypoint ignores this. When a boat is crossing my path I often steer to its stern.. which changes as he moves across my path... The skipper can see that I am taking a decision to avoid a collision and not even pass in front of his bow.
A waypoint may be many miles away... and steering to one ignores the local environment.
As I mentioned I often enter waypoint coordinates and my instruments are providing data for that point relative to my present position.
So let's say I am moving in a strong cross current and the waypoint is 90°. I will turn the course dial and observe what is the COG is and make it 90°... I may actually be heading 100° but set to 90° by the current... So I can sail almost perfectly straight course (shortest) to my destination / "waypoint". Any typically I have to do a lot of "dodging" of boats... and that is no problem the way I use the AP. This shows the difference between the course line and the heading line.
World Map Gadget Font Output device

Looks like I can pass safely between the buoy "15" and buoy "2". Track is light magenta line
 

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Mark... I do not continually have my hand on the dial and steer. I can steer that way through the mooring field to the fuel dock and then release the AP and do the "landing" manually. That sort of maneuver demand more helm turn than any AP can do.

By active I mean I am observing conditions and tweaking the AP heading accordingly or as needed. I can and often do enter a "choke point" ... beginning of a "channel" where boats are converging and emerging...usually motoring or motor sailing steering with the AP dial. I am evaluating the traffic so the actual entry waypoint is not THAT important... it's a channel and there are boats coming and going.... a good place to hand steer.

I often use an old track and follow it in many cases....no waypoint...it's a safe path... I turn my dial to "get on" the old track... which I can follow right to the mooring... or to the channel to the town dock. It's like manual steering... but using the AP dial and not the actual wheel.
 
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