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System redundancy

Feb 29, 2016
System redundancy means having more than one of a particular piece of gear like multiple boathooks.

System redundancy means having more than one of a particular piece of gear like multiple boathooks.

Eric Sanford

To the editor: In a perfect world, I’d have two identical boats always tied next to each other. Of course, in a perfect world I wouldn’t need two boats because nothing would ever break. Classic Catch-22.

While I actually do own two boats, they are very different and not particularly useful for swapping out broken parts. They are so dissimilar — one is a 46-foot sailing catamaran and one is a 43-foot power trawler — that I find myself in a constant state of confusion over the various systems’ operations when I go from one boat to the other.

Both boats, however, do have one thing in common: system redundancy whenever reasonable.

The catamaran starts with several inherent redundant systems, from the two hulls to the two motors to the two props to the two rudders. Making things easy, the motors are also identical, meaning two identical alternators as well as lots of spare parts that fit both motors (belts, filters, pumps, hoses, etc.). Of course there are also two props and two rudders, meaning if one breaks or fails, the spare is already in place. This is one of the great things about a cat: There is basically two of everything of importance.

Taking this one step further, I went through my list of systems I consider either critical or really nice to have and started doubling up. For instance, rather than having one big watermaker, I have two identical smaller ones. So if one breaks, it’s no problem — I’ve got a spare already in place as well as lots of identical spare parts. The same with my autopilot, except that both are quite robust. Having gone through the ordeal of having my autopilot stop working in the middle of a long crossing with big seas, I decided that the safety and peace-of-mind factors of having a spare far outweighed the cost.

Twin water tanks.

Eric Sanford

Redundant safety systems seem like a no-brainer: extra life jackets, flares, fire extinguishers, spotlights, personal EPIRBs, etc. We keep this stuff in a couple of different places so if for any reason one location is not accessible, we’ll still have access to the gear.

My most redundant system is our chartplotters, each with their own set of charts installed. We back up our Raymarine plotter with a MaxSea system that ties into all the wind instruments on the cat. Then I have two iPads: one at the helm and one at the nav station. One has Garmin BlueCharts and one has Navionics charts. I compare the charts on all four systems and sometimes there are differences. Thus, when in doubt, I have a mental system of looking at all four, plus a paper chart and guidebook if available, as well as using binoculars and making the best educated guess as to the proper route. If I relied on just one system, I’d have run aground several times.

I have some items on board that having a spare for might not normally be considered: a handheld depth sounder, spare binoculars, personal EPIRB (to supplement the large McMurdo strapped by the door), handheld wind gauge and compass, several headlamps, extra inflatable PFDs and safety harnesses and even iPads.

A word on iPads: Apart from the one drawback that they don’t have a backlit screen so are thus difficult to read in bring sunlight, having an iPad (or two!) with a chartplotting app is a no-brainer. You can pick up a used iPad2 for a couple hundred dollars. Add a $50 chart app (price includes charts) and a $3 anchor alarm app and you have a really great system. My iPads also connect wirelessly to my Raymarine instruments so I can control the boat from anywhere. There are many waterproof cases available for less than $100.

Of course, extra tools are essential and I have a redundant set of the tools I use most often in the engine room of my trawler, as well as a small set (wrenches, pliers, screw drivers) in each engine room in my cat. There’s nothing more frustrating than climbing in and out of a cramped engine room simply to retrieve the proper tool for whatever job you are doing. In this way I also have spares of my most essential tools. Many times you can “make do” with an alternate tool (such as using an adjustable wrench instead of the exact size, or using the back of a big pipe wrench for a hammer), but for specialty tools I have a spare. 

Two radios means not only having a backup in case of failure, but other practical uses as well — for example, a second radio for communications to the boat for a crewmember going ashore.

Eric Sanford

Having two rigged and ready anchors is a luxury at times, and a necessity at other times. Spare anchors are pretty much mandatory if you are actually cruising. I actually have three on each of my boats, my thinking being that I always want to have two anchors; if I only have two and I lose one, I’ll still have a spare. Overkill? Sure… until you lose an anchor.

There are perhaps 20 pumps, all of different sizes and uses, on my cat and probably close to that number on my trawler. Fresh water, salt water, head water, macerator, motor coolant, reverse cycle A/C, refrigeration, air (for tender, bike tires, inflatable kayaks, etc.), hydraulic generator (lift and water pumps), autopilot — the list goes on and on. I try, whenever possible, to replace a broken pump with a similar one that is being used somewhere else on the boat. In that way I can store a smaller number of spares.  

On my cat I actually have three separate battery-charging systems, as well as two alternators on each motor. Should those fail, I have six large solar panels along with a spare solar charge controller. On a boat, over time, everything will fail — usually at the worst possible moment. Having a spare part or redundant system at least keeps you in the game when (not if) something goes wrong.

Whenever I need a screw or a hose clamp or a switch or any of a thousand other small boat parts, I always buy two. In that way I am assured, according to the Maritime Laws of Calamity, that I will never need that part again. I will, however, need the part that is 1 mm longer or wider. Back to the store…

The bottom line is that having redundant systems on your boat does not mean that you won’t have failures, only that you’ll be better equipped to deal with them since you’ll already have a spare in place.

—For some unknown reason Eric Sanford decided to double the time he spends fixing broken things on his boat by having two of them. He and his wife Debbie spend their summers cruising the Pacific Northwest on their 43-foot Ocean Alexander and the winters in the Caribbean on their 46-foot Leopard sailing cat. So rather than two of everything, it’s safe to assume he has four.

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