OldDan1943
Guru
- Joined
- Oct 2, 2017
- Messages
- 10,599
- Location
- USA
- Vessel Name
- Kinja
- Vessel Make
- American Tug 34 #116 2008
I do hope they visited a boat yard for a ‘short haul’ to inspect blow the water line.
Who would be using an autopilot in that channel?
Just saw this on Yachtforum. Anyone know what happened?
I have used my autopilot in all kinds of channels in our local area. Montlake cut included. I also watch it like crazy and know how to get wheel command back quickly if I have to.
I also know of people who have completely removed the steering wheel and store it in a handy locker and use their follow up levers for navigating the boat
At least one of the ships shown on Deadliest Catch has only a jog lever at the main helm. I have only job levers at my two wing stations and in the cockpit and tower. Although the pilothouse and flybridge have wheels, I never use them, preferring instead to steer with the autopilot controls and to maneuver with the engines.
Don't be so sure. I had my autopilot lock up at full starboard rudder and it took a while for it to release, even when the A/P was powered off. If your autopilot malfunctions, how can you be sure the wheel will work instantly if needed?
Not all work the same.
My older Raymarine unit could always be steered through, even when "on".
I used mine just about all the time except in docking situations or where it would be just too slow in reacting for traffic or other unusual situations.
Cruising and using it is a lot different than just tooling around.
Don't be so sure. I had my autopilot lock up at full starboard rudder and it took a while for it to release, even when the A/P was powered off. If your autopilot malfunctions, how can you be sure the wheel will work instantly if needed?
Boat name?
I don't doubt what you are saying. I use mine all the time and not just "tooling around". So I was just trying to say is that don't assume you can immediately grab the wheel and steer in an emergency if you need to. You can't predict what may happen in a malfunction. I especially wouldn't want to use it in an extremely narrow and shallow channel even if it could be disabled quickly.
..... the first drill I did whenever using an autopilot for the first time on a strange boat (commercial, delivery, friends, etc) I would command the pilot to turn, then see if I could steer through it the opposite way.
If concerned about an autopilot freak out and having to try to fight the system when the A/P pump is stuck on in one direction or something, you could always install a switch or breaker near the helm to cut power to the A/P pump. Then it doesn't matter if it's stuck in a bad state, it can't mess with your manual steering.
Knowing your gear is tantamount to using it safely.
Many APs have three modes although called different things by different brands
ND-no drift (what I may use in narrow channels)
Go To- gets you to a waypoint
Course- called A on simrad. Steers a compass course
.....I wouldn’t throw stones at the owner/operator for using a AP. Neither would I assume he was at fault with the information available. Possibilities include a failure of judgment but also electronics failure, discrepancies between charting and reality, hydraulic failure, fly by wire failure.
Many APs have three modes although called different things by different brands
ND-no drift (what I may use in narrow channels)
Go To- gets you to a waypoint
Course- called A on simrad. Steers a compass course
For boats with hydraulic steering lock to lock maybe several turns and the AP steers much faster at slow speeds. Have taken to alternating between standby and one of the three modes when going through skinny water. Also have taken to putting rudder angle indicator on one of the small screens when up in the flybridge. The principle helm has a separate dedicated rudder angle indicator.
In short you dance with the girl you brought to the dance. I wouldn’t throw stones at the owner/operator for using a AP. Neither would I assume he was at fault with the information available. Possibilities include a failure of judgment but also electronics failure, discrepancies between charting and reality, hydraulic failure, fly by wire failure.
Both prior RM, garmin, and current simrad products have had handheld remotes for the AP. I will use them in open ocean when the depth is so deep it doesn’t read but the three dashes but never in skinny water. Find them intermittently unreliable. That’s yet another possibility.
Thanks - never heard of the "ND" option. I assume it's a very narrow XTE setting. Good idea for narrow channels.
That is how the NAV or GOTO function works. Compensates for drift so boat may be on a course of 270 but with northerly winds pushing her south, shows a compass heading of 275 with slight starboard rudder correction to compensate. In short, it will do whatever it needs to do to minimize XTE - distance from the imaginary line snapped to the Waypoint when NAV is engaged. On AUTO, the operator would be responsible for reconciling drift by altering course from time to time, or calculating the set and steering 275 from the outset. Before sophisticated autopiliots, this was very common when crossing the Gulfstream from Florida to the Bahamas.My understanding of how that mode works on most APs is that instead of tracking a compass course, it takes the desired course and your starting position (when you engage the mode) and sets a virtual waypoint some really long distance off in that direction, then tracks to that waypoint. So instead of tracking a heading of, say, 170*, the effective behavior is to track a course over ground of 170*.
That is how the NAV or GOTO function works. Compensates for drift so boat may be on a course of 270 but with northerly winds pushing her south, shows a compass heading of 275 with slight starboard rudder correction to compensate. In short, it will do whatever it needs to do to minimize XTE - distance from the imaginary line snapped to the Waypoint when NAV is engaged. On AUTO, the operator would be responsible for reconciling drift by altering course from time to time, or calculating the set and steering 275 from the outset. Before sophisticated autopiliots, this was very common when crossing the Gulfstream from Florida to the Bahamas.
My understanding of Hippocampus' post is there is a ND setting where tolerance for XTE is very low. You could manually change this, but sounds like there is a simple setting to do so. Interesting feature (assuming I understand it correctly)
Peter
Many thanks. That's even more cool than my assumed mode! Very usefulThe ND setting (called advanced auto on some pilots) is basically a combination of the 2 modes. You still give the autopilot a compass course to follow, but it internally uses the nav mode with a virtual waypoint (vs one you feed over from the plotter) to track that course over ground.
That mode does need GPS data available, but you don't have to plot a waypoint and tell the AP to go to it. You just tell it to steer 270* in that mode and it'll compensate for set/drift for you (vs blindly steering 270* like in the basic auto mode).
Costa Lot?I think it's Costa something