Route programing, auto pilot and the AICW

[Jklotz]

My training captain said not to program a route and use auto pilot on the icw. Heading hold was ok for short, straight passages where the depth was good and I was sitting at the helm monitoring closely, but his recommendation was just to hand steer unless I'm out in open water. Being stuck at the dock waiting for repairs, I had plenty of time, so playing with Aquamaps, I created a route, very closely following Bob423's tracks, up the ICW to the next town up, about a 64nm run and ported it over to my Garmin chart plotter. Charts are up to date. Auto pilot is a newer/current Garmin and is functioning properly.

My question is why shouldn't I choose to use this route on autopilot if I'm at the helm monitoring the whole time. I'm pretty sure it could follow the track better than I could steer it. There was no auto routing involved and I zoomed in really close, making sure I was dead on the track, especially around bridges, shoaling areas, marinas, etc.

 

[mvweebles]

Good question. Many of the responses to a recent thread on chart packages folks are using (HERE) suggested many people do not use their AP in NAV mode (some Simrad devices call this "TRACK"). To level set, here are the modes though the nomenclature varies between brands. I am least familiar with Garmin so no idea what they call the functions.

STBY (Standby). AP is not engaged. Hand steering.

AUTO. Autopilot is engaged and steering to a compass heading. Does not correct for set or drift induced by current or wind.

ND (No Drift). Not sure how many APs have this mode - Simrad calls it No Drift. Essentially AUTO mode but course is corrected for set/drift. Requires a GPS/Heading input. In practice, this is very close to GOTO.

GOTO. Navigate to a waypoint or dropped mark. Very similar to ND. AP compensates for set and drift.

NAV ("Track"). A waypoint or route is engaged and the AP steers to the waypoint correcting for set and drift.

With definitions out of the way, why did your training captain suggest hand steer or perhaps AUTO? What was his argument against NAV/GOTO (or ND if Garmin supports it)? Or do I not understand what his guidance was?

In my opinion, when navigating in long channels such as the ICW, compensating for set/drift between AToNs (channel markers) is invaluable. The marks can be pretty far apart and cross winds or currents can cause imperceptible drift out of the channel. One of the drift-compensated modes (NAV, GOTO, ND) is extremely helpful. Using AUTO or hand steering requires manual compensation which means you have to constantly look backwards to see if you're on a straight line between markers.

I have no qualms with routes (NAV) in the ICW but it still requires a sharp lookout. Frankly, the waypoints are often at sharp turns so you end up going out of NAV to smooth the turn but having the full route engaged gives interesting arrival information.

Personally, I set a GOTO/ND waypoint right between channel markers to assure I stay in the channel. Of course I'll need to move to starboard if there's oncoming traffic but that's my general strategy.

Bottom line is, assuming I understand correctly, I am damn curious why your training captain advises not compensating for set and drift. Maybe I'm missing something but sure seems like you'd be leaving a valuable tool fallow.

Peter

 

[Don L]

I used to account for drift etc mainly by watching the depth. I noted over the years that power boats seemed to go aground more often because they would say "we were in deep water and then went aground" . But their "deep" water was 8' which met they were already out of the channel really.

Also far as I am concerned "Bob's tracks" is a fools game. Stay in the channel, follow the markers, don't cut corners (boaters do this a lot", be aware there will be shoaling in places with creeks etc. flowing into the ICW.

Track setting in AP has no business being used anywhere with twisty narrow channels.

 

[rslifkin]

In fairly calm, protected waters like the ICW hand steering is generally pretty easy as the boat isn't getting pushed around all that much. And you usually have good visual reference to steer to plus plenty of traffic and other factors to adjust for, so it's unlikely you'd be able to let the AP steer for all that long before needing to adjust.

I'd tend to agree with hand steering in the more curvy areas with traffic, but go ahead and use the AP to hold course on longer straight sections without much traffic. Ideally you'd use it in the "no drift" mode that mvweebles mentioned. Most modern autopilots have some version of it (Furuno calls it advanced auto, for example). That mode basically maintains your course over ground instead of maintaining heading.

When you get to the open sounds, etc. that's the time to take full advantage of the AP and let it follow a route.

 

[Fleming]

I'm of the same mindset as your training captain. Yes, most of the ICW is boring and easy, but every now and then a new shoal pops up, boats are passing you and going the other way fast, cross currents, buoys change position, etc. Letting your GPS drive the boat instead of your eyes and brain is a relaxation of your watch standing duties beyond what I'm comfortable with. I know the response to that statement is "I'm still watching and monitoring" but that's different than actually driving the boat and the reduced attention needed is, well, reduced attention.

I also hate hand steering, so I use compass headings with the autopilot and steer by constantly adjusting course with the AP instead of grabbing the wheel unless things get exciting and I need to hand steer.

 

[Gdavid]

One consideration to keep in mind is how your autopilot adjusts your heading to reduce the cross-track error (XTE) when in navigation mode. The XTE is simply the shortest distance you are at any given time from the route that you have set. If your boat wandered off course one boat length, your XTE would only be 45' for example.

Like mentioned above, navigation mode compensates for current and wind to keep you within your selected cross track error limit. The manner in which the autopilot makes this correction can be abrupt and surprising when you are monitoring your course at the helm, it can be especially unnerving if there are other boats in the area because the correction can be a pretty significant change in course. I have had a couple occasions in both overtaking or crossing situations where my autopilot appeared to lose its mind and turn sharply towards the other boat, it was not based on magnetic influence of the compass or any error, the boat had simply reached the maximum XTE that I had set in the autopilot and it occurred at an inopportune time. Fortunately, I was paying attention and just put the AP in standby mode, but the first time it happened I was quite perplexed. I've found that keeping an eye on your XTE is a good idea even if you aren't in a tight channel because you will be able to anticipate when the AP is about to make a course correction. I suspect the newer units can make these adjustments earlier and less dramatically, but it is influenced by your settings. I've found allowing a more generous allowance for XTE reduces this frequency. I hope this makes sense.

(edited in an attempt at clarity)

 

[boomerang]

I use my pilot just like I use the cruise control in a car. Every chance I get. For a pilot to be worth a darn, it needs to be set up correctly ,which every one of mine are. I keep a watch as anyone who uses a pilot is supposed to do but heck, I keep ours on going through canals and tighter channels, adjusting the course in 1 or 2 degree increments, but only in the auto mode. I does a better job of holding a course than I can do and as far as I'm concerned, it allows me to keep a better situational awareness.
Training captains are like any other business operation, there's good ones and bad ones. Just because you have a 6-pack licence doesn't necessarily mean you give good boating advice.
Agree with the above. Those dang folks who blindly follow bob tracks aren't doing the rest of us any favors. I've been forced out of the channel several times by boat drivers with their nose stuck in the screen of their tablet following the dotted line. Pay attention to the markers and follow them, keeping in mind that occasionally they're off station. If they (the markers) don't look right and you're doubtful of the channel, slow down! I tell my wife when she's at the helm in the waterway to pretend she's running a tug pushing a barge. Don't run up and kiss every marker...make big sweeping turns like a 150-200' vessel would do and more than likely, you'll be good.

 

[Iggy]

I can only say what I do.

I do plan a route but not have the AP itself follow it. I turn on the AP and use it to steer. Mainly using the route as a guide. This also keeps me alert and there are always small course corrections needed. Due to lobster pods, junk in the water, other boaters, and anything else.

The other thing, the AP can react better than me. Wind and current sometimes makes it harder to hand steer.

To have the AP follow the course on its own, is good in wide open waters. For me even coastal, I will not do it.

 

[mvweebles]

The attached picture is a bit blurry but bear with me. Green line on radar is heading (direction the bow is pointed); orange/dashed line is bearing to waypoint. There is a 14-degree variance. Why? Because the Gulf Stream is pushing the boat to port so the helm compensates by pointing the boat to starboard. Why trust the AP in open water and not in closer quarters? If the AP isn't doing it's job, fire it (of course we all know it does a fine job). The radar picture is on a N55 which is very difficult to hand-steer (as are many trawlers). APs do a great job - especially in close quarters.

Scaling the example from the picture down to the ICW, if you're in a channel with 1-nm between markers and an uncompensated side-drift of 10-degrees; you'll be 500-feet off your track line halfway through. In wide open waters, that can be difficult to detect manually.

Assuming the OP's 2022 NP45's autopilot is even close to being configured properly, it will maintain a cross track error (XTE) of less than 10-feet (probably less than 5-feet). How is hand-steering better than that? It doesn't care that there is wind or current pushing it sideways - will compensate just as the picture shows.

Why is using the AP a bad thing? How is hand steering (or AUTO) better? A large percentage of boats I've run have not had their APs well configured and tend to serpentine but assuming that problem is solved, how is riding-on-rails to the next waypoint a bad thing?

Peter

 

[rslifkin]

Why is using the AP a bad thing? How is hand steering (or AUTO) better? A large percentage of boats I've run have not had their APs well configured and tend to serpentine but assuming that problem is solved, how is riding-on-rails to the next waypoint a bad thing?

In most cases it's a good thing. But in confined busy waters with good visual reference to steer to you can end up in a situation where the workload of constantly adjusting the autopilot as the channel winds around and you encounter other traffic ends up being higher than the effort of hand steering.

At least on my boat with hydraulic steering where the rudders don't back-drive the helm it's pretty easy to hand steer in confined waters. You just make small adjustments to the helm for curves, traffic, etc. For a long, sweeping turn you can just tweak the helm a little off center and sit there while the boat gently follows the curve. To me, autopilot isn't a significant workload reduction in an environment like that. In open water it's a totally different story.

 

[mvweebles]

I keep ours on going through canals and tighter channels, adjusting the course in 1 or 2 degree increments, but only in the auto mode. I does a better job of holding a course than I can do and as far as I'm concerned,

I steer using AUTO and small adjustments a lot too, especially larger boats where hand-steering doesn't work well. Heck, many larger boats don't even come with a wheel anymore - everything is pump driven.

Peter

 

[mvweebles]

In most cases it's a good thing. But in confined busy waters with good visual reference to steer to you can end up in a situation where the workload of constantly adjusting the autopilot as the channel winds around and you encounter other traffic ends up being higher than the effort of hand steering.

There will always be a case for hand steering, but the OP's direction was to never use the AP in ICW-type situations. Whether you use AUTO and make incremental course corrections (and manually adjust for set/drift) or you use NAV/TRACK/ND (whatever) and let the GPS/Sat Compass make the set/drift corrections for you, there is simply no way hand-steering can maintain the same XTE as an AP. Not using the tool is a missed opportunity in my opinion.

So, of the people who think you should not use the AP in ICW-type channels, why? If it's because your boat won't keep a straight course on AP, well that's a different problem.

Peter

 

[Shrew]

I use autopilot based on heading. I don't have autopilot follow the plotted course. I keep an eye on the plotted course, set auto-pilot and adjust manually as needed. My wife joking says "Ah, I see you're steering with the 'little wheel', since my Raymarine uses a knob to adjust heading.

This is like a hybrid. You can go for stretches without actively steering while still being able to respond to changes. I don't care how easy it is, wake, waves, wind, current all push you. You have to actively steer which can get mentally tiring after hours. AP by heading allows you to make adjustments periodically. I see I'm slowly creeping towards the edge of a channel...adjust.

 

[ranger58sb]

My training captain said not to program a route and use auto pilot on the icw. Heading hold was ok for short, straight passages where the depth was good and I was sitting at the helm monitoring closely, but his recommendation was just to hand steer unless I'm out in open water. Being stuck at the dock waiting for repairs, I had plenty of time, so playing with Aquamaps, I created a route, very closely following Bob423's tracks, up the ICW to the next town up, about a 64nm run and ported it over to my Garmin chart plotter. Charts are up to date. Auto pilot is a newer/current Garmin and is functioning properly.

My question is why shouldn't I choose to use this route on autopilot if I'm at the helm monitoring the whole time. I'm pretty sure it could follow the track better than I could steer it. There was no auto routing involved and I zoomed in really close, making sure I was dead on the track, especially around bridges, shoaling areas, marinas,

We usually use AUTO (heading hold) mode to "go straight" as often as is reasonably possible -- making small adjustments along the way as necessary.

But we do not bother to create routes; too time consuming, not worth my effort. And a route would have to be redone every year, given shoaling and moved ATONs and so forth. Bob's track is OK but not gospel. We've intentionally chosen different routing through various areas for various reasons like traffic; shoaling; moved markers; set and drift due to tide, wind, currents, whatever; etc.

Some of the ICW is larger water, and a pre-defined route wouldn't be as risky, less prone to traffic, but... still not worth my time and effort.

-Chris

 

[mvweebles]

One consideration to keep in mind is how your autopilot adjusts your heading to reduce the cross-track error (XTE) when in navigation mode. The XTE is simply the shortest distance you are at any given time from the route that you have set. If your boat wandered off course one boat length, your XTE would only be 45' for example.

Like mentioned above, navigation mode compensates for current and wind to keep you within your selected cross track error limit. The manner in which the autopilot makes this correction can be abrupt and surprising when you are monitoring your course at the helm, it can be especially unnerving if there are other boats in the area because the correction can be a pretty significant change in course. I have had a couple occasions in both overtaking or crossing situations where my autopilot appeared to lose its mind and turn sharply towards the other boat, it was not based on magnetic influence of the compass or any error, the boat had simply reached the maximum XTE that I had set in the autopilot and it occurred at an inopportune time. Fortunately, I was paying attention and just put the AP in standby mode, but the first time it happened I was quite perplexed. I've found that keeping an eye on your XTE is a good idea even if you aren't in a tight channel because you will be able to anticipate when the AP is about to make a course correction. I suspect the newer units can make these adjustments earlier and less dramatically, but it is influenced by your settings. I've found allowing a more generous allowance for XTE reduces this frequency. I hope this makes sense.

(edited in an attempt at clarity)

To build on this, a very common AP-induced "Crazy Ivan" is when the operator needs to dodge or pass and goes into STBY or AUTO and manually steers for a bit. APs are pretty dumb devices - all they really know is XTE - if there is a distance, they close it. That's it. So hitting NAV when you're well off the courseline means the AP will make a sharp correction to get back to the courseline. There are adjustments within the AP to reduce this intensity. But usually one of the following two ways is easier:

• After you've dodged, stay in STBY or AUTO and slowly return to the courseline (reduce XTE to zero) and then resume NAV; or
• Most APs have a "GOTO from here" type function that resets the courseline to your current location. In essence, resets XTE to zero.

Peter

 

[Portage_Bay]

I never let the autopilot follow a route in confined waters. Depending upon the boat and installed equipment I would "hand steer" with the AP. Get settled on my course, set the AP to hold that heading, adjust the AP as needed which was very frequently. The AP will hold my course if I need to pay attention to something else for a few seconds but I am steering. I wouldn't do it through a MFD that controls the AP. The AP needs to have something like a knob that adjust heading easily. I need to be able to instantly disconnect the AP, a single button press or a switch. The AP has to have the capability to easily adjust course and the heading sensor needs to be accurate enough.

You said your training captain recommended to not use the AP in route following mode in confined waters. That you are learning under a training captain suggests a lack of familiarity whit the boat and possible lack of experience in boating in general. If that is true then hand steering at first is a very good idea to learn the boat. How much rudder is needed to turn. Is counter rudder needed to settle on the new course. How fast does she respond. What are the effects of wind and current from different direction. You won't learn the boats attributes without some time hand steering.

 

[mvweebles]

I never let the autopilot follow a route in confined waters.

Why?

 

[Dennis C]

Never use Auto Routing Period. Usually use auto on the ICW and sit with my hand held remote and move a degree or two as necessary unless there is a big bend or other boats around where I need to hand steer around them. Then back to Auto.

 

[Portage_Bay]

Why?

To be sure we are discussing the same thing when I say I won't let the AP follow a route in confined waters I'm talking about a route of more than two waypoints, especially a route automatically generated.

In my post I described "hand steer" by AP, that is adjusting the heading when in hold heading mode.

The reason is that I think it important that the helmsman be fully engaged in the process of piloting the boat in confined waters. By hands on the controls, looking out the windows and observing nav aids i.e. plotter, radar and AIS. No distractions. No adhering to a route I created or the system auto generated. Too many things can change too fast. Even the briefest inattention can end in a bad way. Constant changes need to be made for any number of reasons.

Then there is the consideration of accuracy of the positioning, heading and electronic charts. Finally the tendency to let the AP following a route be the final decision. I've see more than a few mistakes made that way by others.


Let me describe what I mean by confined waters. A narrow canal, passing under a bridge, rounding blind corners in a narrow waterway and natural obstacles resulting in a narrow safe channel.

I've tried letting the AP do the job following a route in those conditions. It didn't take me long to decide the risk reward ratio was not good.

Once out in more open waters but still not what I consider open waters I'll step up in automation. A simple route of two way points. Adjust as needed. The advantage here is that the AP is not simply holding a heading but compensating for cross track error from winds and currents. It's a little harder for me to define those waters, so much depends upon local conditions and traffic.

 

[mvweebles]

To be sure we are discussing the same thing when I say I won't let the AP follow a route in confined waters I'm talking about a route of more than two waypoints, especially a route automatically generated.

In my post I described "hand steer" by AP, that is adjusting the heading when in hold heading mode.

The reason is that I think it important that the helmsman be fully engaged in the process of piloting the boat in confined waters. By hands on the controls, looking out the windows and observing nav aids i.e. plotter, radar and AIS. No distractions. No adhering to a route I created or the system auto generated. Too many things can change too fast. Even the briefest inattention can end in a bad way. Constant changes need to be made for any number of reasons.

Then there is the consideration of accuracy of the positioning, heading and electronic charts. Finally the tendency to let the AP following a route be the final decision. I've see more than a few mistakes made that way by others.


Let me describe what I mean by confined waters. A narrow canal, passing under a bridge, rounding blind corners in a narrow waterway and natural obstacles resulting in a narrow safe channel.

I've tried letting the AP do the job following a route in those conditions. It didn't take me long to decide the risk reward ratio was not good.

Once out in more open waters but still not what I consider open waters I'll step up in automation. A simple route of two way points. Adjust as needed. The advantage here is that the AP is not simply holding a heading but compensating for cross track error from winds and currents. It's a little harder for me to define those waters, so much depends upon local conditions and traffic.

I agree with much (perhaps all?) of what you're saying. Going through a bridge or fairway are good examples of where an AP has no place.

But the OP asked about the AICW which is a horse of a slightly different color. I personally find the buoyage a bit confusing - the main channel has red to landward side, green to seaward side. No problem there (well, manageable problem - it's not always obvious). But there are a ton of channels off the main AICW that conform to conventional red-right-return signage. It doesn't take long before you are confronted with an unexpected color buoy. It looks so clear on the charts. But out on the water with vast expanses of nothing rimmed by featureless landscape is different. Having the route dialed in as the OP asked really helps.

Mind you, I'm not suggesting anything close to set-and-forget route guidance and NAV. All I'm saying is that if you set a waypoint between a red/green set of channel markers and set another waypoint between the next set of red/green channel markers, a correctly setup AP will follow the line (NAV/TRACK or ND/GOTO) with very little XTE no matter the adverse conditions. Thats a good thing and marked improvement over AUTO or STBY (hand steer).

Peter

 

[Jeff F]

I also hate hand steering, so I use compass headings with the autopilot and steer by constantly adjusting course with the AP instead of grabbing the wheel unless things get exciting and I need to hand steer.

That's my approach as well, with an occasional GOTO a waypoint, which is useful in currents particularly, or longer open water stretches. Generally I never touch the wheel unless going through bridges or other big steel structures.

I can't imagine following someone else's route. Maybe that's just me. It took me a while before I clued into the hoards who follow Bob423. Now I'd make an effort to avoid that track to stay out of the parade.

 

[lwarden]

I don’t have much need for auto-routing here in SoCal but experimented with it up when we were in the PNW. I used it to plot the shortest direction through a series of islands to find the shortest route and it worked well for that, but never used the routing it for control of the AP, I just used the heading hold to roughly follow the route. I was really curious to find out how many who routinely follow the ICW plot and navigate with all the available tools we have.

When we were back at the AGLCA rendezvous last weekend I had a chance to talk with several “Loopers” about this current topic since I was interested in what people were doing. From the folks I spoke to, most do pre-route planning on tablets or PC’s, using TimeZero, Navionics or AquaMaps which seem to be the most common apps. They incorporate information when planning using Waterway Guide or Bob432 and consider this when plotting the route on their tablet/PC, then export this to their main MFD chart plotter via GPX and program like Active Captain. I gather people are using a combination of AP following the route when practical and hand steering when appropriate or when safety dictates. Now, this transfer from tablet to MFD is the clunkiest step since there does not appear to be a seamless and bi-directional way to export from their tablet to the MFD, or back to the tablet/PC. In the session on tablet navigation, I asked the presenter why this is still so awkward, especially the transfer from Navionics to Garmin which should be seamless since Garmin has owned Navionics for a while. The answer was that NMEA2K standard does not have a format to send route data, just waypoints. I think this is well known by many on this forum. From my perspective, this is a major flaw in NMEA2K and it should be addressed so there is a proper way to share routing.

 

[Portage_Bay]

I have so little experience of the AICW I'll call it zero. I have navigated areas where there are enough crossing and converging channels that it looks as if someone knocked a christmas tree over at night. Even in those area I won't let the AP follow a route. I'll create a route then follow it myself. I'm still reluctant to use auto generated routes for anything other than a quick and dirty distance in unfamiliar waters. Partly because I enjoy navigation, even the point and click creation of a route on a plotter. I study the detail and make the decisions myself. I will note that I do my route planning on a PC not a MFD. Much easier on a PC. MFD route planning takes more patience than I have.

I agree with much (perhaps all?) of what you're saying. Going through a bridge or fairway are good examples of where an AP has no place.

But the OP asked about the AICW which is a horse of a slightly different color. I personally find the buoyage a bit confusing - the main channel has red to landward side, green to seaward side. No problem there (well, manageable problem - it's not always obvious). But there are a ton of channels off the main AICW that conform to conventional red-right-return signage. It doesn't take long before you are confronted with an unexpected color buoy. It looks so clear on the charts. But out on the water with vast expanses of nothing rimmed by featureless landscape is different. Having the route dialed in as the OP asked really helps.

Mind you, I'm not suggesting anything close to set-and-forget route guidance and NAV. All I'm saying is that if you set a waypoint between a red/green set of channel markers and set another waypoint between the next set of red/green channel markers, a correctly setup AP will follow the line (NAV/TRACK or ND/GOTO) with very little XTE no matter the adverse conditions. Thats a good thing and marked improvement over AUTO or STBY (hand steer).

Peter

 

[Seevee]

I use autorouting all the time. Did it with my Simrad unit in my previous boat and with my Garmin in my current boat. Why not???

If you don't know what your autopilot will do, I could argue to learn what it CAN do and what parameters it will hold. AND USE IT!

My Simrad autoroute was better than the Garmin, but a bit more difficult to program, but never missed a beat. Garmin, not quite so good and at times I had to intervene.

However, I could argue that you can't trust a boat autopilot 100%, and need to always monitor it. Unlike a airplane autopilot that you can trust with your lift (some of them). I've done a few cat III landings where the AP will land the plane, without me seeing the runway. The only thing is I feel the wheels touch down, and I put it in reverse. You don't have that with boats.... too bad.

But boat autopilots do have some predictability and if you know what your AP will do you can trust it for running in the ICW and it can work well.

When I followed Bobs tracks on the AICW, I found them very accurate, but made minor adjustments as necessary, but very few.

If I create a route on Navionics and download to my AP, it's also very accurate. The autorouting feature is the least accurate, but super easy to use and a great feature.

Now, on all of the AP usage on a boat, I or my co captain will monitor it 100%.

 

[mvweebles]

I don't use nor do I recommend auto-routing except for very high level distance calculation. it might be a start but you have to go through it in its entirety to check the route (BTW - the OP didn't say he used auto routing, but he did say he zoomed and checked the route carefully).

But I still don't understand the concern about letting a properly setup AP drive a boat in NAV/ND/GOTO on the ICW. I believe I have pointed out many reasons why AP is better than human steering (either STBY or AUTO). Not just me, but for decades, every thread on APs has had a chorus that APs steer better than any human can. Part of that is the ability to reduce XTE to near zero. Running the AP reduces human error factor substantially.

I'm not trying to be obstinate but just trying to push a bit to ask whether there are demonstrable reasons for doing/not doing something or if is just "that's how I've always done it "

Why is AP not good enough for steering on the ICW?

Peter

 

[Jklotz]

I do know, from our shakedown cruise, that on my boat, the AP in heading mode, drives in a vastly superior straight line than I was able to steer it. The old owner left his breadcrumb tracks on the plotter and it was obvious which were done with the AP and which were hand steered.

 

[ranger58sb]

I do know, from our shakedown cruise, that on my boat, the AP in heading mode, drives in a vastly superior straight line than I was able to steer it. The old owner left his breadcrumb tracks on the plotter and it was obvious which were done with the AP and which were hand steered.

That's pretty typical.

Something I forgot to say earlier: The AICW isn't a single kind of waterway along its distance. Some skinny, some wide. Some deep, some shallow. Some windey, some straight. Some built up, some desolate. Et cetera.

We've run from Ft. Lauderdale to Annapolis, From Ft. Myers to Annapolis, and we've done a few trips back and forth from Annapolis to Jacksonville and Charleston... and each shorter stretch of waterway is kinda unique.

I do think many of the wider/deeper areas could be managed easily enough with routes; we just don't bother with all that, only use our AP (a lot) in go-straight mode with tweeks along the way. Even the idea of loading Bob's tracks directly into our systems and creating routes from that... don't much ring my chimes... but I think that's more about my approach to time management than a criticism of the technique.

And then for skinnier/shallower areas, even though we still use the go-straight machine, much of our "piloting" starts relying on instantaneous depth readings, charted depth readings (and USACE survey info), immediate tide levels, water color, ripples (or not), immediate impact of current or wind, other landmarks (old docks, etc.), and the way the waterway bends...

Besides, I do kinda "enjoy" (if that's the word) working out our path on the fly, with charts but also that other visual input from markers, terrain, water color, etc etc etc.

Wandering off... I discovered TZ Navigator will do auto-routing. Haven't tried to see what that's all about, how to do it, etc. Can't say I'm too enthused, other than maybe for first-pass guesswork for going places we've never been by boat. Maine, for example, or whatever...

-Chris

 

[Jklotz]

I played with auto routing on the Garmin CP last night. Zoomed way in, it was taking me places I wouldn't take my boat. About the only useful thing I could see with it is a quick way to measure distance, but by the time I edited it to make any sense for navigation, seems a lot easier to just start in AM and just make from scratch.

 

[mvweebles]

Here's a pretty extreme example but by no means uncommon and is representative of the ICW/AICW.

Chart of Lake Okechobee. Approx 7-miles between channel markers and you're in the middle of the lake with zero references because land is 4-miles away. 15-kt wind from the east is pretty common.

NAV/TRACK/Whatever will put you exactly on the trackline with only gentle monitoring of the MFD so you can pay attention to other stuff such as other boats. AUTO will require constant monitoring of the MFD and course correction.

 

[O C Diver]

I spent a lot of time on several ICWs, canals and channels. Never used routing between waypoints. For long stretchs in bays and sounds, I would select a destination and let the autopilot take me to the destination, not cross track error. Most of the time I would use the autopilot to hold course heading with a remote that allowed either a knob for major course corrections or arrow buttons to correct course for a degree or three. I traveled on autopilot 99% of the time. It obviously is important to get it dialed in where the boat feels like it's running on rails.

Below is the Dismal Swamp canal. I transmitted it on autopilot.

One of the reasons I resisted routing waypoints and cross track error was the self focus on monitoring with occasional corrections. For me, it's too easy to have too much faith in the autopilot. I trusted it, but only continuously monitoring it. How else will you avoid all the floating hazards, navigation marks and other boaters.

Ted