Superyacht: Licence to fill (with water...)

[captgs]

Well, it was the GPS's fault. Anyone knows if you are 49 feet from shore you are good to go.

15 metres from shore in a vessel of almost 50 metres in length does not seem prudent.

 

[Hippocampus]

Remain wondering why this happened. How did “gps “ result in a large vessel striking and flooding.

 

[Comodave]

We have reached some sort of zenith here, if quoting Below Deck as a source for anything. Just saying.

Well the superyachts in charter are always looking for qualified crew and captains. So if they are having trouble finding crew then don’t you think that other superyacht owners may also be having trouble finding qualified, in other words good, crew? Maybe the reason so many superyachts are sinking or crashing is because the pool of qualified crew has been diluted by the recent upsurge in the number of superyachts.

 

[chriscritchett]

Well the superyachts in charter are always looking for qualified crew and captains. So if they are having trouble finding crew then don’t you think that other superyacht owners may also be having trouble finding qualified, in other words good, crew? Maybe the reason so many superyachts are sinking or crashing is because the pool of qualified crew has been diluted by the recent upsurge in the number of superyachts.

Just giving you sh*t for the reality TV reference. Sorry if it was only funny to me.

I’m sure ‘you cant get good help these days’ is a universal issue and is in fact causing issues.

 

[DDW]

No AP pump is powered by the N2K backbone. It is powered by the course computer, which should have its own breaker. If there are two steering stations then it needs two breakers. Having anything capable of controlling the boat, which you do not have absolute authority over with an air gap in easy reach, is something that would be corrected on my boat before it left port. I've had an AP hard over failure (flux gate compass) and heard or read about several others - this does happen.

 

[Hippocampus]

Going back to the boat in the AM. Still don’t have the precision 9. But with the old one should be able to check out what breaker controls the computer. Nothing is labeled as such on this new to us boat. Will report back with more information afterwards.

 

[hjorgan]

If the insurance papers get too close to the GPS it can throw it off badly.

 

[Hippocampus]

Today put in the second new precision 9 compass and then went out to calibrate it. All went fine except do to wind and current it took several tries until we were totally satisfied t was good to go. Had the opportunity to flick switches. Although there’s no power button on the AP there is a breaker at the pilot house station that turns off the AP computer and makes the AP pump inactive. Still have no way to to it off at the flybridge. As stated before the prior event occurred while in standby. So that’s not helpful. So have three ways to shut it down. Turn off te AP computer at the pilot house breaker sub panel. Turn off the whole sub panel at the nav station breaker panels. Turn off the DC panel master switch (which leaves on key things like pumps and engine controls (they’re on separate breakers.
Problem is I still would need to get to the pilot house or nav station to regain manual steering. No breakers at all up there.

If I ever catch no current and no wind will recalibrate again. But system accepted the current one and did some “go tos” and some routing to waypoints while checking true and magnetic and everything seems fine for now.

 

[RT Firefly]

Greetings,
Mr. (Dr.) H. How difficult might it be to install the appropriate switch in the FB?

 

[KnotYet]

Greetings,
Mr. (Dr.) H. How difficult might it be to install the appropriate switch in the FB?

For example a light gauge of wire could operate a conveniently located relay.
This would avoid running the actual power wires up to the FB and back down.

 

[twistedtree]

The failure Hippo describes does indeed sound quite rare. I've heard of lots of Crazy Ivans, but never uncommanded steering in Standby. As mentioned, the solution is to turn off the AP breaker which kills power to the AP computer which is what controls the steering pump.


I don't think I have ever heard of a boat where a breaker is controlled from two locations. You could do that, but I'd be more inclined to go after the root problem which seems to be some combination of the Precision 9 which you have pretty clearly shown to be unreliable, or the AP itself which has shown itself to be vulnerable to N2K misoperation.



Given your experience so far with the Precision 9 compass, I'd suggest you seriously consider a satellite compass. They are infinitely better than a magnetic rate compass, and are under $1000 at this point. It's easy for me to spend your money, but the $1000 is way less than the deductible on your insurance for any collission/allision damage that a failed Precision 9 may cause.

 

[psneeld]

For example a light gauge of wire could operate a conveniently located relay.
This would avoid running the actual power wires up to the FB and back down.

Have a real electrical guy think this through before attempting....Also if just isolating the pump, put in 2 relays (redundancy) and now you don't necessarily loose display functions but eliminate the pump driving the rudder anymore with this setup.

Use a guarded switch so it's always energized with a latching on/off relay (not hot solenoid/power drain).

Check with manufacturer of AP computer making sure it will not be hurt by severing power to AP pump while computer is on.

Shold be an easy and inexpensive fix if it is reviewed and recommended.

 

[Hippocampus]

Thanks for the suggestions gentlemen. The Precision 9 was replaced under warranty so don’t know cost but believe it’s around $700. The jump to satellite would be trivial. However the 9 is in there and paid for by warranty. Have also been told this is a rare failure if the unit is a good one. I did RI to VA twice on the original unit and have used the boat locally as well before failure. So I’m a bit nervous it might fail again. If it does I’ll be off warranty and would definitely use a satellite unit. Do you have any to suggest?

Running another wire seems difficult although there’s an existing run from flybridge to bridge. Currently run is very clean and well done. Looks like either disturb that or drill more holes. Don’t know enough to know if a computer breaker can be done. Tech I used said no go. But over the years have found worth asking around for multiple inputs.

Given there’s two of us on the boat and admiral knows how to turn off the computer will dance with the girl I brought for now. Thanks for the input..

 

[AdkChris]

Wealthy get the benefit of the doubt?

I find it kind of interesting that the posts are mostly about hardware failures and the difficulty of finding good help. Seems to me that if this happened to a more modest boat the conversation would be about human failures.
Seems the assumption is that because someone has an awful lot of money they must be competent boat owners. Lord knows there are no examples out there of people whose sole talent is accruing (inheriting) wealth and who use that wealth to buy toys well beyond their skills and surround themselves with incompetent yesmen.

 

[DDW]

You could put a breaker in the autopilot pump line, but it would be just as easy - if you already have a breaker at the PH and a run from there to the FB - to put a series breaker to the course computer at the FB. There is no way tripping this will cause the autopilot harm unless it is a really, really bad design (it should be an expected event). While a sat compass might remove the P9 from the equation, the breaker solves all ills, from whatever source they arise.

A breaker between computer and drive motor has at least some theoretical potential to do some harm, sudden disconnect from an inductive load driven by FETs, etc.

 

[Art]

No boat handling problems due to electric or gps equipment breakdowns! Redundant pilot stations.

 

[Shrew]

Wealthy get the benefit of the doubt?

I find it kind of interesting that the posts are mostly about hardware failures and the difficulty of finding good help. Seems to me that if this happened to a more modest boat the conversation would be about human failures.
Seems the assumption is that because someone has an awful lot of money they must be competent boat owners. Lord knows there are no examples out there of people whose sole talent is accruing (inheriting) wealth and who use that wealth to buy toys well beyond their skills and surround themselves with incompetent yesmen.

It' simply because wealthy people who own superyachts pay professional crew with accreditation.

Professional crew are less likely (yes, commercial vessels have accidents) to have accidents of inattention. The large portion of accidents on commercial vessels (again, not all) are mechanical failures.

Small, non-commercial vessels are are operated by recreational boaters with significantly less experience and no accreditation is required. These folks have a higher probability of being in navigational accidents.

In short, it looks that way, because it is that way.

 

[wkearney99]

This occurred to our little thing last week. My understanding is with NMEA 2000 and everything on the backbone failure of one thing can corrupt the function of other things. Our Precision 9 compass failed. This caused the AP pump to drive the rudder to port. Got a screen message “rudder angle >25 degrees. There’s no easy way to turn it off without turning off all electronics. This occurred just before entering our marinas channel which is very narrow. The approach is narrow as well and bordered on both sides by big rocks. We usually turn off the AP( that really means going to standby as there’s no power switch on the device. It’s on anytime the 2000 backbone has power). check the thrusters and reverse before entering the approach. That’s when the rudder went to port. We used the thrusters to line up with wind and current. We were fortunate to get a side tow on a Sunday from the yard. We needed both its big outboards and our thrusters to get into the slip. In retrospect should have just turned off everything connected to the NMEA background and gone in hand steering (assuming hand steering would have returned).

I have separate power breakers at the helm for autopilot, NMEA2K, radar and each nav station. It would seem foolish not to. I generally run with the AP breaker OFF until it's actually needed. I've dealt with heading sensor shenanigans in the past.

Which AP setup? Does it not have a simple disengage/stop function?

 

[wkearney99]

Given your experience so far with the Precision 9 compass, I'd suggest you seriously consider a satellite compass. They are infinitely better than a magnetic rate compass, and are under $1000 at this point. It's easy for me to spend your money, but the $1000 is way less than the deductible on your insurance for any collission/allision damage that a failed Precision 9 may cause.

I have been very pleased with the Furuno SCX20 I had put on ours last season. The trouble lately is getting them, I hear they're backordered.

 

[Hippocampus]

Yup backordered.
From what tech says either turning off all electronics or just the AP computer shouldn’t do any harm. But will get the no AP computer alarm repetitively. Do have navionics on several IPads so will probably shut off electronics entirely in an emergency. Have acquaintances who gone RTW on IPads and no MFDs so don’t see that as the end of the world. Just need to be more diligent about looking at depths on the chart and visually scanning for traffic until you’re sorted things out.
Have no issues turning things off in the pilot house. Have gotten different approaches for dealing with the flybridge station. Haven’t decided yet which to follow.

 

[wkearney99]

But will get the no AP computer alarm repetitively.

Yeah, this is annoying. I get that with the radar on the new TZT16F I put in last season. The old NN3D setup didn't raise errors if you powered off the radar unit unless you were on the radar pages. Well, the red X would appear over the icon, but it didn't bug you repeatedly about it. I dislike that the TZT16F can't just dismiss this error to silence it until the next reboot.

As for hard power cycling, modern chartplotters do have more active use of their storage so it's wise to use the shutdown method for them instead of just flipping off their breakers.

 

[twistedtree]

For what it's worth, I once encountered a situations with an AP where cycling the AP computer breaker would not clear the fault, but cycling the N2K backbone power breaker would clear it. In some ways this makes sense because the N2K interface on devices is sometimes powered from the N2K bus, not from the devices main power supply. So that portion remains active even when the devices main breaker is cycles. A bug there remain "active" until N2K power is cycles.


This was a simrad pilot, BTW. It would appear as though the computer had been rendered brain dead, and a couple were even replaced under warranty until I accidentally stumbled onto this. The dreaded "autopilot not found" message was the clue. It turned out you could recover them by cycling both the computer and the N2K breakers at the same time. I ultimately figured out how to break the computer as well, so could reproduce the whole thing on-demand. I have not seen any software updates from Simrad on the pilots since I reported this to them, so I assume the bug is still there.

 

[wkearney99]

This makes me think this could have been among the reasons why my initial attempts to use some Simrad AP26 controls with an N2K bus might have had more trouble than I was expecting. I went back to keeping them separately connected to the AC20 autopilot computer. Until a year later when the rudder unit and one of the control heads died, then I gave up on it.

There are such things as N2K power isolators. Where the data is passed but not power.
https://www.amazon.com/gp/product/B00ABI6BF4

One of these would seems like it'd help if you placed it in-line between the AP and the N2K bus. It would allow normal operations to proceed without any change but would prevent it from providing power back onto the N2K bus.

A side note, the N2K bus is probably pickier about power and cabling than a lot of folks take into consideration.

 

[Hippocampus]

Excellent information. Take home. Turn off electronics breaker and AP computer. Then only turn on electronics leaving AP off. Years ago was taught to individuality turn off devices with 0183 (especially allowing radar to gradually power down). That was before digital radar. Still hold to that practice out of habit. On the day in question I was up on th flybridge (by myself). Admiral down setting up lines/fenders. No headsets as “been there done that” often enough. She had no idea what was going on. Won’t do that again. In retrospect should have just called her on her cell. Now will use the headsets more going forward. Issue is these are rare events but now see this vulnerability.