Nordhavn vs Fleming vs Kady Krogen

[greatpapabear]

Redundant systems need maintenance too. Easily neglected. Should be used frequently.

This is so true.

For example, imagine you are in an 'emotional' sea and your satellite compass fails causing multiple warnings on your chart plotter, radar and autopilot. How easily can you change to your fluxgate without reference to any checklists you may have.

And just as important, when did you last check the fluxgate was operational?

 

[twistedtree]

This is a key point about redundancy vs simplicity. For example if you have two gensets and need both to be operational for peace of mind, it really means twice as long sitting at the dock waiting for repairs or parts over the course of your ownership.

Yes and no.


Redundant systems definitely means more maintenance and repair. And more complexity, and more cost.


But the whole idea is that it means LESS time sitting at the dock, not more. Both parts of the redundant system don't need to be working to continue on. That's the whole point. With one broken you lose redundancy, but you can keep going.

 

[twistedtree]

This is so true.

For example, imagine you are in an 'emotional' sea and your satellite compass fails causing multiple warnings on your chart plotter, radar and autopilot. How easily can you change to your fluxgate without reference to any checklists you may have.

And just as important, when did you last check the fluxgate was operational?

Agreed. Both are important parts of the system design. With electronic devices like in your example, it's often possible to have the fail over happen automatically. Worst case it can be done with a switch.


And health monitoring of both is essential. I found Maretron's system was very helpful to that end. I was able to create a dedicated display page that showed all the redundant instruments, side by side. At a glance you could see that both were producing data, and that it agreed. It's also possible to alarm on loss of data.

 

[greatpapabear]

Agreed. Both are important parts of the system design. With electronic devices like in your example, it's often possible to have the fail over happen automatically. Worst case it can be done with a switch.


And health monitoring of both is essential. I found Maretron's system was very helpful to that end. I was able to create a dedicated display page that showed all the redundant instruments, side by side. At a glance you could see that both were producing data, and that it agreed. It's also possible to alarm on loss of data.

If you have a sat compass and fluxgate and using NN3D, you have to reset the NN3D and alter the set up. A long a delicate process. Painful - no short cuts, so knowing what needs to be done is vital.

 

[Steve DAntonio]

This is my question exactly. More than a few people have said this on TF and in other forums. But what exactly makes the Nordhavns more complex?

Redundancy is expected and I would hope it would be the case for the KKs as well. Nords seem to have a reputation for ease of new first time owner operation. I like that because I am a new to be owner. Bow and stern thrusters with a wireless remote control makes docking easy but isn't that available on other trawlers? Are the control systems over engineered? As an engineer I like that too. Is the hull thicker, window glass heaver? What does add to the complexity?

There are right and wrong ways to do complex. Doing it right requires an investment in design and engineering that many builders avoid, they simply install the gear for the intended purpose without proper integration and coordination. A few years ago I wrote an article on this very subject, using a recently built Nordhavn as an example, you can read it here https://stevedmarineconsulting.com/the-trend-toward-complexity-2/

I routinely hear the phrase, "you've got to keep it simple", but these vessels, in this ocean-crossing category, are not simple, buyers of vessels in this class don't want to take a step backward from the safety, redundancy, comfort and convenience of their homes, cars and aircraft, it's tantamount to telling the buyer of a luxury vehicle that he has to have roll up windows, because they are simpler and more reliable than electric. Buyers are driving the complexity, builders are simply answering the call. Complex also often equates to more capable and versatile.

I'm no advocate of unnecessary complexity, or complexity married to poor design/execution, those vessels are problematic and not enjoyable to own.

With proper design, engineering and execution, you can have both complex and reliable, it just comes at a cost.

 

[Magneto]

Well said Steve.

Let me ask this question: If a boat such as a newer Nordhavn was to suffer a lightning strike taking out the electronics beyond repair at sea, can the engines be ran manually? Can the boat be piloted to safety with some bypassing?

 

[twistedtree]

If you have a sat compass and fluxgate and using NN3D, you have to reset the NN3D and alter the set up. A long a delicate process. Painful - no short cuts, so knowing what needs to be done is vital.

Ouch, that is a pain. Have you experimented with any work arounds? Does one come in on NMEA 2000, and the other on 0183?

 

[greatpapabear]

Annoyingly, you can't have an auto change-over. It's a reprogram. Apart from that, the NN3D is superb and the best chart plotter I've found, although I haven't tried the newer TZ Touch series.

 

[twistedtree]

I think the key is to get what you want/need, but accomplish it in the simplest way.


The very "simplest" solution is to just ignore the problem. No problem, no solution needed.


But assuming that's not your goal, there is always a spectrum of solutions to any problem, some more complex than others. I think the art is to find the simplest solution that solves the problem to your satisfaction.


For example, the boat Steve wrote about above pioneered a much simpler way to provide backup/redundancy for black and gray water overboard discharge. Previous solutions involved carrying spare pumps to replace a failed pump, or to plumb both an electric pump and a manual pump in series so the manual pump could be used if the electric failed.


The simpler solution was to cross valve the black and gray water pumps and tanks so either pump could be used to pump either tank. If one pump fails, you just use the other pump by operating a valve. It's quick to use and doesn't involve any extra equipment except for the valves.

 

[DavidM]

Steve's article is perhaps an extreme case of redundant systems engineering and installation to survive failures and keep almost everything running as before. That doubles or even more the cost and maintenance required. But let's look at a more simple version that accepts some degradation in case of failure but none life threatening:

Propulsion: Single engine with a wing get home engine supplied by two fuel tanks that are independent of each other. Independent starting systems.

AC power generation: Main large genset and a smaller night time and emergency power genset.

DC power generation: Twin high output alternators with independent regulation on the main engine and a high output one on the wing engine.

DC power storage and distribution: One main battery bank and another to provide emergency power for communication and navigation, properly isolated with independent distribution wiring.

Navigation: Twin radar domes feeding two separate chart plotters, the secondary fed from the emergency DC system.

Water: Sufficient tankage to make it to the farthest port, and/or redundant water makers, one smaller and fed from the emergency DC system. Spare pumps on board.

The list goes on. But the idea is that the primary systems provide all of the comforts required and the secondary system is usually smaller and provides safety. The cost and also the maintenance required will be less than just that monster inverter that Steve describes in his article.

The trick is to keep the secondary systems exercised so that they will be ready to step in when required.

David

 

[twistedtree]

Steve's article is perhaps an extreme case of redundant systems engineering and installation to survive failures and keep almost everything running as before. That doubles or even more the cost and maintenance required. But let's look at a more simple version that accepts some degradation in case of failure but none life threatening:

Propulsion: Single engine with a wing get home engine supplied by two fuel tanks that are independent of each other. Independent starting systems.

AC power generation: Main large genset and a smaller night time and emergency power genset.

DC power generation: Twin high output alternators with independent regulation on the main engine and a high output one on the wing engine.

DC power storage and distribution: One main battery bank and another to provide emergency power for communication and navigation, properly isolated with independent distribution wiring.

Navigation: Twin radar domes feeding two separate chart plotters, the secondary fed from the emergency DC system.

Water: Sufficient tankage to make it to the farthest port, and/or redundant water makers, one smaller and fed from the emergency DC system. Spare pumps on board.

The list goes on. But the idea is that the primary systems provide all of the comforts required and the secondary system is usually smaller and provides safety. The cost and also the maintenance required will be less than just that monster inverter that Steve describes in his article.

The trick is to keep the secondary systems exercised so that they will be ready to step in when required.

David

I think that's all very doable.


By way of further example, on our last boat I trimmed back on a few things from your list.


I had one generator, not two. If the generator failed and I couldn't fix it, I would lose air conditioning which is an inconvenience, but not the end of the world. And I had 7kw of main engine alternators, so could still charge batteries.


My wing alternator was not high output, but I could run the generator for ships power, and for hydraulics for stabilization if the main was out.


I had one water maker, and just kept the tank full enough to get where we were going with reduced consumption.


So those are some examples of lower costs ways to keep going even if something breaks.

 

[sunchaser]

Over the years I have found, as have others, that an overzealous owner or less than capable tech hands cause mayhem in systems, particularly electronics. The upshot is only the previous owner knows how things really work, or not.

I've one friend who recently re-did his Nordhavn's nav system electronics because too many hands had been involved in the original setups. Another Nordhavn owner suffering from similar "how does it work" questions became so frustrated that he sold the boat and ordered a new Nordhavn done "right."

Back to Papa Bear's question on flux and satellite compasses tied into NN3D. I've a Furuno tech friend who says no problem if setup right, whatever that means. That said the work around (if possible) is one that likely only a few others would ever know about. But, NN3s are real bargains and if one has the space another NN3 can be installed with each having their own compass. Or just pitch the flux gate and get another satellite compass.

Point being, show some pity for the next owner. Do it right and logical the first time.

 

[greatpapabear]

Over the years I have found, as have others, that an overzealous owner or less than capable tech hands cause mayhem in systems, particularly electronics. The upshot is only the previous owner knows how things really work, or not.

I've one friend who recently re-did his Nordhavn's nav system electronics because too many hands had been involved in the original setups. Another Nordhavn owner suffering from similar "how does it work" questions became so frustrated that he sold the boat and ordered a new Nordhavn done "right."

Back to Papa Bear's question on flux and satellite compasses tied into NN3D. I've a Furuno tech friend who says no problem if setup right, whatever that means. That said the work around (if possible) is one that likely only a few others would ever know about. But, NN3s are real bargains and if one has the space another NN3 can be installed with each having their own compass. Or just pitch the flux gate and get another satellite compass.

Point being, show some pity for the next owner. Do it right and logical the first time.

I'd LOVE to know how your Furuno tech friend managed to set the system up. Is it poss to find out?

 

[sunchaser]

I'd LOVE to know how your Furuno tech friend managed to set the system up. Is it poss to find out?

Yes. I will contact him. It has been over a year since we last talked on this particular subject. Right now he is in BC and I'm not there for another month or so. PM me your email and I'll get you guys together. Also forward me the basics on your current NN3 setup, hubs, interfaces, compasses etc.

 

[greatpapabear]

Yes. I will contact him. It has been over a year since we last talked on this particular subject. Right now he is in BC and I'm not there for another month or so. PM me your email and I'll get you guys together. Also forward me the basics on your current NN3 setup, hubs, interfaces, compasses etc.

Brilliant. Will PM you immediately, if not sooner.

 

[Simi 60]

I think that's all very doable.


By way of further example, on our last boat I trimmed back on a few things from your list.


I had one generator, not two. If the generator failed and I couldn't fix it, I would lose air conditioning which is an inconvenience, but not the end of the world. And I had 7kw of main engine alternators, so could still charge batteries.


My wing alternator was not high output, but I could run the generator for ships power, and for hydraulics for stabilization if the main was out.


I had one water maker, and just kept the tank full enough to get where we were going with reduced consumption.


So those are some examples of lower costs ways to keep going even if something breaks.

Further steps again for us luddites

If our genset dies we have 2200kw of solar.
Genset only used on rainy days.
Engine alt puts in around 60amps @1150rpm which is 4x our usage
Boat is well ventilated and shaded with no accom below decks so no aircon required living in the same latitudes as Florida.

No water maker but we carry 5 tonne of water plus have rain collection and a 200 litre bladder in the tender. In 4 years cruising we usually only top up water at a fuel dock twice a year when down to our last tonne of water.

For navigation we have taken the Admiral Adama / Battlestar Galactica approach and shunned networking.
We have a stand alone Seiwa chart plotter using a 23 inch monitor
A stand alone small form factor PC running opencpn on a 2nd 23 inch monitor

Downstairs way from everything as backup we have a laptop running opencpn
And multiple tablets with navionics and downloaded charting.
Nothing interlinked and everything has its own GPS and spare GPS antennas are onboard.

If auto pilot dies I have the same complete model sitting in the spares locker but she holds a course well so hand steering is not the end of the world

We have a single radar which I can live without, cruised all through Vanuatu, New Caledonia and East coast of Australian without one and didn't die once.

 

[Simi 60]

Well said Steve.

Let me ask this question: If a boat such as a newer Nordhavn was to suffer a lightning strike taking out the electronics beyond repair at sea, can the engines be ran manually? Can the boat be piloted to safety with some bypassing?

Great question
Electronic engine controls up in smoke.
What next?

 

[MYTraveler]

If you have a sat compass and fluxgate and using NN3D, you have to reset the NN3D and alter the set up. A long a delicate process. Painful - no short cuts, so knowing what needs to be done is vital.

Actually, at least with TZTProfessional (and maybe with NN3D), you can create configuration files in advance. Then it is a simple matter of loading a different configuration file. And it really isn't that tough to program, at least not after you get the hang of it.

 

[twistedtree]

Great question
Electronic engine controls up in smoke.
What next?

I think you're forked. Carry a spare ECU.


I think lightening is one of the few things that can really take everything out. Pretty scary to think about.


I know lots of people will now extol the virtues of mechanical engines, but they haven't been available in typical trawler HP ranges for 10+ years, no not really a viable option for many of us.

 

[IRENE]

Does anyone know the feasibility of stocking a spare ECU? It appears they are a little over a boat unit for my JD4045. Is tucking one away in a faraday bag overkill?

 

[cardude01]

Do people carry spare ECUs? Seems like a good spare to carry.

 

[twistedtree]

Does anyone know the feasibility of stocking a spare ECU? It appears they are a little over a boat unit for my JD4045. Is tucking one away in a faraday bag overkill?

I know a few people who have kept a spare. But I don't know anyone who has been hit by lightening, lost and ECU, and repaired it themselves with a spare. I think the trouble is that lightening can take out so much, and in such an unpredictable pattern. Even if you get the engine running, will the shift and throttle work?


I wonder how bigger ships deal with this?

 

[Simi 60]

I think you're forked. Carry a spare ECU.


I think lightening is one of the few things that can really take everything out. Pretty scary to think about.


I know lots of people will now extol the virtues of mechanical engines, but they haven't been available in typical trawler HP ranges for 10+ years, no not really a viable option for many of us.

Wouldn't contemplate getting something good rebuilt?
Gardner's, jimmies, cats , cummins etc

Still selling brand new 855s in Oz.

Cummins NTA855-M350 Marine Engine - Brand New - Filter Discounters

 

[Simi 60]

. Even if you get the engine running, will the shift and throttle work?

Its why I questioned it before.
Electronic engine controls use a wire that can go anywhere so have they even left space for push pull Morse cabling in them when they build?

Even if our cables broke I could jury rig string, its a straight clean run with plenty of space on ours.

I wonder how bigger ships deal with this?

Bloke in the ER perhaps?

 

[Sailor of Fortune]

I think the risk is over hyped... does it happen? yup, to someone ,somewhere...Just like lottery winners and peeps struck by lightning.

 

[twistedtree]

I think the risk is over hyped... does it happen? yup, to someone ,somewhere...Just like lottery winners and peeps struck by lightning.

I think you are probably right.


You've had a lot of time at sea. Ever been struck? I imagine a steel hull would be the best to have, giving lots of paths for energy to dissipate.


I hadn't really thought of until now, but on our new boat I have the engines and gear/throttle controls powered off the start batteries. Actually redundantly powered off two different start banks used across the engines and generators. The result is that they are isolated from the rest of the boat's power system, I think. That would give them some greater degree of isolation from a lightening hit? I think that's what I'll choose to believe.

 

[Steve DAntonio]

Well said Steve.

Let me ask this question: If a boat such as a newer Nordhavn was to suffer a lightning strike taking out the electronics beyond repair at sea, can the engines be ran manually? Can the boat be piloted to safety with some bypassing?

This issue is relevant for any modern vessel with electronically-controlled diesels; lightning is unpredictable, anyone who says he or she can predict what it will do, or prevent a strike is, well, not credible in my opinion. Stats for trawler/motor-yacht strikes are about 1.5/1000, that's pretty good odds, while multi-hulls are a whopping 6.9/1000, the highest strike likelihood of any vessel type.

It's a valid concern, but the odds of a strike are, one again low for this vessel type.

Nordhavns and others have been struck by lightning, suffering some damage but not to engines, while others have been struck and left dead in the water. This has much less to do with complex vessels and more to do with modern diesel engines, which are a fact of life for every vessel that's been built in the last 20 years, with an engine over 100hp.

If disabled by a strike, most electronically controlled diesels are DOA, there is no 'manual' mode. Some cruisers do carry a spare ECU, but that's not as easy to do as it sounds, it's not a simple case of taking it out of a box and swapping out the dead unit, they need to be programmed in advance by a dealer.

With some exceptions, most Nordhavns up to about 76 feet use primary manual, non-electronic/electric hydraulic steering (even most larger ones with full AC powered electro-hyd steering have a full manual mode), so you may find yourself hand steering in the event of a lightning strike if APs are taken out, so you could steer, but it would be a workout, because these vessels are very difficult to steer manually. Broadly speaking, most larger Nordhavn owners steer much of the time using the AP in nav or power steer mode (I recently completed construction on a N68 that has full electro-hydraulic steering for this reason, the owner wanted to be able to steer with the wheel, there's that pesky complexity vs. convenience thing again). Nodhavns in the size range you are looking at, I think you said 60, have provisions for manual steering using a manual tiller, but it's unlikely you'd need to use the emergency tiller as a result of a lightning strike, as the manual hydraulics would still work.

What Nordhavns do well is bonding and grounding, while it's not fully ABYC complaint for lightning protection (almost no power vessel is, however, most N's do meet ABYC E2 Cathodic Bonding Systems), it has a very solid bonding system, compliant ground plate and air terminal. In my experience, vessels with robust bonding systems suffer less damage when struck by lightning. More on the subject here https://www.proboat.com/2016/04/3530/

 

[Sailor of Fortune]

I have never been struck. I was next to the Miss Gloucester in the mid 80's when she got struck. We were out on Stellwagon bank. Fried all his wh electronics and knocked Billy (capt) to the deck... Many years on commercial boats have never been hit (knock wood).

 

[mcarthur]

This issue is relevant for any modern vessel with electronically-controlled diesels; lightning is unpredictable, anyone who says he or she can predict what it will do, or prevent a strike is, well, not credible in my opinion. Stats for trawler/motor-yacht strikes are about 1.5/1000, that's pretty good odds, while multi-hulls are a whopping 6.9/1000, the highest strike likelihood of any vessel type.

Steve, is that "multi-hulls" meaning sailing vessels or power only? Because if it's sailing (or sailing AND power), you're comparing trawler/motor-yacht with short/no mast with multihull sailing boats with, lets face it, cloud-penetrating aluminium lightning attractors - quite different beasts...

 

[greatpapabear]

Let me ask this question: If a boat such as a newer Nordhavn was to suffer a lightning strike taking out the electronics beyond repair at sea, can the engines be ran manually? Can the boat be piloted to safety with some bypassing?

One of the reasons I love our Fleming's pre-electronic controlled engines. I believe these were the last of the non-electronically controlled engines they made. Throttles and gears are hydraulic controls.

(a pair of Cummins 6CTA 8.8 M3)