Electronics refit on Irwin 43

[sailjumanji]

Originally Posted by malyea

- satcom (maybe SSB in the future)
- EPIRB

Ok, for communications I am going to purchase a receive-only SSB, to get the Chris Parker forecasts. I guess you can also use it with some software and a laptop to get GRIB files, etc., but to be honest, playing with a PC is not my idea of cruising. Plus we don't even have a nav station below!

Some people love their SSB transceivers, and talking on the nets, etc. Again, it looked like a lot of equipment and expense, and other than weather I couldn't see a real need.

OTOH, I did buy a Spectra watermaker - which can be powered by the solar panels and save me from lugging 5 gal jugs of water from the island spigots. Or require a marina stay for fillup. Decision was made easier when I found someone with a two-year old unit still in the box, changed plans, and wanted to sell it. I'm sure my wife is going to like not having to limit fresh water use, which will hopefully mean more cruises in our future.

We did buy an InReach SE with will give position updates to family following us (posts it on a webpage) every ten minutes, as well as allows two-way texting - all thru the same satellites as Iridium. Subscription can be on a month-to-month basis. I will also pick up a cell phone in the Bahamas. The InReach has an SOS function that may or may not be as good as the EPIRB. OTOH, it will notify authorities and allows for communication with them via texts - so maybe it is better.

[Sandero]

Originally Posted by Terra Nova

I want the autopilot to go where I tell it to go, and to always be under my control, not the control of several other possibly faulty black boxes.

This is absolutely correct. When it's NOT under your control it can act on its own and get you into trouble because it is not AWARE of everything in the environment such as a floating hazard and approaching vessel on a collision course.

People who use interfaces are LAZY and a bit stupid really. It takes very little effort to turn a dial to make a course correction.... not to mention that the winds and sea state are changing all the time and so a straight line course may not be optimal.

[skipmac]

Originally Posted by Sandero

This is absolutely correct. When it's NOT under your control it can act on its own and get you into trouble because it is not AWARE of everything in the environment such as a floating hazard and approaching vessel on a collision course.

People who use interfaces are LAZY and a bit stupid really. It takes very little effort to turn a dial to make a course correction.... not to mention that the winds and sea state are changing all the time and so a straight line course may not be optimal.

I'm not certain I even understand what your saying but from what I do think I see then this all so totally incorrect. An AP is no more and no less under your control whether or not it is integrated with other systems, uses a windvane sensor OR as all APs must in the most basic mode, a compass sensor.

These are all just different ways for an AP to set and maintain a heading. Just referencing to one or another external black box. Whether that black box is a compass to set a magnetic based course or a GPS to set a course to a waypoint you, the captain has the same control in either case. I do agree that if you use a wind sensor to set a course then you, the captain, will have to be aware of wind shifts and understand that the boats course will change with the wind. That doesn't mean you have lost control of the boat, just means you have to understand how that system works and use ti correctly.

Just because an AP is steering to a wind angle or to a waypoint instead of a compass course how does that change the need to keep watch and avoiding a vessel or any other hazard? AP steering by compass course isn't going to do anything to avoid another vessel any more that steering to a waypoint or wind angle.

[colemj]

Originally Posted by Sandero

This is absolutely correct. When it's NOT under your control it can act on its own and get you into trouble because it is not AWARE of everything in the environment such as a floating hazard and approaching vessel on a collision course.

People who use interfaces are LAZY and a bit stupid really. It takes very little effort to turn a dial to make a course correction.... not to mention that the winds and sea state are changing all the time and so a straight line course may not be optimal.

I suspect you have very little experience with different autopilots and integrated systems - with any experience you do have being very old.

How is your basic non-integrated autopilot aware of its environment to the extent that it can avoid a floating hazard or approaching vessel?

How does setting your autopilot to a compass course not constitute a "straight line course" and how does it adapt itself to changing sea and wind conditions?

How does an autopilot navigating to a waypoint, or navigating in a no-drift mode go off "acting on its own" and "getting you into trouble"?

Just the opposite - an autopilot navigating to a waypoint or in no-drift mode will not experience unintentional leeway or drift. Likewise, an autopilot operating in wind mode will follow the wind around as it shifts - which is exactly what a person expects and wants from this mode.

If a mechanical wind vane is considered acceptable, why is an autopilot integrated with a wind instrument not acceptable (and lazy and stupid)?

An autopilot operating in compass mode can lead the boat well off course or off wind before an operator can notice. Do you sleep on passage? Go to the bathroom? Make meals?

Stupidity is not understanding, or refusing to open one's mind, to alternates, while doggedly clinging to an unexamined belief despite realities.

Mark

[Terra Nova]

Right, stupidity is not doing it exactly how Mark does it.

[colemj]

Originally Posted by Terra Nova

Right, stupidity is not doing it exactly how Mark does it.

Only an ad-hominum attack, or can you actually address any of the issues and questions I have raised?

Mark

[Stu Jackson]

Originally Posted by Terra Nova

Right, stupidity is not doing it exactly how Mark does it.

Time for another sarcasm emoticon?

Really, the power of integration, whether one chooses to do so or not, has been explained quite well in this thread.

Most "old school types" fail to take into the account the VERY important concept that the AP doesn't "DO"anything until it gets a confirming "yes" response from the skipper.

It's not like the ap are doing what motorboaters too often still do, and are the butt of jokes from the early days of aps.

The power of integration these days is far above the early days and can be very beneficial.

Think of it this way: it gives you even MORE time to conn the boat, you're not doing navigation tasks but have more time for look out.

As always, it's simply your choice where you want to spend your $$.

Would I do full integration for a Bahamas trip if I lived in FL? Would I do it for coastal hopping here in California or even to Mexico?

No, but that's my choice. Others, with the same criteria and plans would do it differently, and many have.

The beauty of this thread is that what's happening is not the integration vs. no integration, but the specificity and knowledge of the particular equipment that is available and their pros & cons.

Great stuff. THAT'S what this conversation should be.

[sailjumanji]

I use my AP, a lot. And I have used it to steer to a waypoint, to steer to apparent wind (while I was sitting on the front net, watching the system account for minor wind shifts - very cool), and steer to compass. Whether it was set that way thru a MFD, a computer (display head), or a button on the pilot - although I can honestly say I have never seen one with the referenced "dial" - I don't think really matters. Just be ready to take over when conditions dictate. No one is advocating that the AP take the place of someone on watch and aware.

That said, there is a cat in our marina that was making a long voyage with two crew. They set a waypoint at a piling of some type. Owner went below to sleep; the other crew was left on watch and eventually fell asleep. The boat sailed right into the piling, crunched the front crossbeam, damaged the front deck, and they were lucky the forestay didn't part and lose the mast. There is one time that they wished the old, less-accurate GPS system was in place, and they might have skirted by. I think we can all agree that one was just plain stupid.

[sailjumanji]

Originally Posted by Stu Jackson

Would I do full integration for a Bahamas trip if I lived in FL? Would I do it for coastal hopping here in California or even to Mexico?

No, but that's my choice. Others, with the same criteria and plans would do it differently, and many have.

Maybe you might do it if you were taking your boat from California to the Bahamas.

[colemj]

Originally Posted by Stu Jackson

Would I do full integration for a Bahamas trip if I lived in FL? Would I do it for coastal hopping here in California or even to Mexico?

No, but that's my choice. Others, with the same criteria and plans would do it differently, and many have.

If you were buying new equipment, you probably couldn't get away from integration since most pieces now have a small cable that connects them to the data bus. You could always not connect this cable, but why not? For an autopilot, not connecting that cable may not work anyway, since it will need to see the compass data and control head at a minimum - one just gets all other data on this small cable as a bonus.

I don't see any difference between coastal and offshore when it comes to "integration", since the only difference is whether or not one plugs the cable in.

Nobody has to USE the integrated functionality, of course, but to actively seek out non-integratable equipment doesn't make sense to me. Particularly when you consider that those types of equipment are generally old technology - you will get a mechanically gimbaled compass on an autopilot, for example, and that will probably not be a rate compass.

And then when that compass has a problem, you can't just easily switch over to the secondary compass already on your network, or instead use COG from the GPS on your network to drive the AP. If your control head goes bad, you can't switch over to the redundant MFD control already available.

Your AP won't have any STW or COG data available to adjust its steering parameters, so it will be arcing you around while you try to constantly zero out yaw and over/understeer by twiddling knobs. If the winds are shifty, you will be working hard to maintain VMG - grinding winches and twiddling knobs.

But some do like to believe that this is a more robust way of safer operation. Personally, I like the redundancy and fail-over abilities of integration - not to mention the smoother and safer operation with greater choices of operating modes of an integrated autopilot.

Many times, I even just set it to a compass course…

Mark

[malyea]

I want a "minimum level" of AP integration such that I can use various steering modes (app wind, mc and direct to WP) but I'd like to protect against "single point" failure that renders my AP useless.

Of all the components required to operate the AP (and this assumes proper, robust installation of the drive unit) I suspect that, because of their exposure to the elements, the MFD or the AP control head is most likely to fail.

I don't want to carry a spare MFD due to significant cost ($3000+) but I might consider carrying a spare AP control head ($450ish). I also doubt I'll carry a spare linear drive on a 7 to 14 day passage.

Fundamentally I am trying to minimize the chance of a mid-ocean single point failure of the AP by designing the system such that no one component failure (like the MFD) results in loss of everything.

Am I on the right track or off on a tangent?

[skipmac]

Originally Posted by sailjumanji

That said, there is a cat in our marina that was making a long voyage with two crew. They set a waypoint at a piling of some type. Owner went below to sleep; the other crew was left on watch and eventually fell asleep. The boat sailed right into the piling, crunched the front crossbeam, damaged the front deck, and they were lucky the forestay didn't part and lose the mast. There is one time that they wished the old, less-accurate GPS system was in place, and they might have skirted by. I think we can all agree that one was just plain stupid.

Exact same thing happened (indirectly) to me. Got together seven friends to do a dive trip to the Bahamas and we chartered a four cabin cat. Arrived in Miami to pick up the boat and the charter company told us the previous charter party, with a paid, licensed captain had set the AP on the way back to the marina and hit an ICW channel marker right between the hulls. Captain was below fixing coffee or something.

[skipmac]

Originally Posted by malyea

I want a "minimum level" of AP integration such that I can use various steering modes (app wind, mc and direct to WP) but I'd like to protect against "single point" failure that renders my AP useless.

Of all the components required to operate the AP (and this assumes proper, robust installation of the drive unit) I suspect that, because of their exposure to the elements, the MFD or the AP control head is most likely to fail.

I don't want to carry a spare MFD due to significant cost ($3000+) but I might consider carrying a spare AP control head ($450ish). I also doubt I'll carry a spare linear drive on a 7 to 14 day passage.

Fundamentally I am trying to minimize the chance of a mid-ocean single point failure of the AP by designing the system such that no one component failure (like the MFD) results in loss of everything.

Am I on the right track or off on a tangent?

Yes, I think you're on the right track but having a single point of failure is inevitable unless you carry spare everything. Basic AP has only one drive unit, one brain, one compass and one control head. Not up to speed on all the new models and features but I think some can be operated by and independent controller or from a MFD screen.

If the wind or GPS input dies you can revert to compass steering.

In my experience the most likely component to fail is the brain which also provides the power to the drive unit. The most complex part of the system. The waterproofing in the control heads is very good and I haven't had one of those fail on me. But I am just a data sample of one; not statistically valid.

[adlib2]

Originally Posted by Terra Nova
I want the autopilot to go where I tell it to go, and to always be under my control, not the control of several other possibly faulty black boxes.

Thought I'd throw this in. On long ocean passages just remember GPS follows a Great Circle and Plotter shows Mercator.
Many a vessel has foundered on an Island or headland with AP following the GPS.
No substitute for the Eyeball.

[colemj]

Originally Posted by malyea

I want a "minimum level" of AP integration such that I can use various steering modes (app wind, mc and direct to WP) but I'd like to protect against "single point" failure that renders my AP useless.

Of all the components required to operate the AP (and this assumes proper, robust installation of the drive unit) I suspect that, because of their exposure to the elements, the MFD or the AP control head is most likely to fail.

I don't want to carry a spare MFD due to significant cost ($3000+) but I might consider carrying a spare AP control head ($450ish). I also doubt I'll carry a spare linear drive on a 7 to 14 day passage.

Fundamentally I am trying to minimize the chance of a mid-ocean single point failure of the AP by designing the system such that no one component failure (like the MFD) results in loss of everything.

Am I on the right track or off on a tangent?

AP integration nowadays is all or none - there is no "minimal", unless you don't have certain instruments on the network (if no wind instrument, your autopilot won't be integrated with wind, for example). The only way to get no integration at all is to not connect the network cable to the AP.

The most common AP failure mode is poor mounting and poor operating environment of the drive unit, followed by poor electrical connection - neither of which has anything to do with the AP itself.

An alternative to a full AP head unit as a spare is a controller. Raymarine has a wireless controller and B&G has both a wired and wireless controller. Both cost less than a full head unit, but don't give all the data and don't have all the modes that are available with a full head unit. There are probably others that I don't know about, but your choice here will depend on which AP system you have.

Modern small MFD's and AP head units are very robust exposed to the elements. Most are bonded displays and fully sealed bodies. Because of this, most have no serviceability in any way - if one goes bad, you throw it out. Simrad/B&G even take care to point out this fact that there is no service with these units. Under warranty, they simply send you a new unit. While this might seem to be a step backward, the positive is that these things can pretty much operate under water now. Besides, modern electronics of all types really can't be "fixed" anymore - one needs a microscope just to see the ancillary surface mount components on the single small board containing the all-in-one microchip.

If you are worried about the compass failing, the autopilot can be switched to COG input if that happens. Most autopilots can still operate without a rudder reference unit if that goes bad. Drive failures are very rare, and generally happen after many years/miles (drives themselves are probably the most robust part of an AP).

That leaves the computer as a failure point with no reasonable backup or workaround. These are expensive and you would have to decide if having a spare is worth it.

Of course a couple of dumbbells to keep your arm muscles in shape is the ultimate backup…

Mark