A Voyager's Guide to Spare Parts
At a recent dock party, I overheard one captain lament, "Every time I turn on the hot water, the boat turns right!" His problem seemed simple enough-an unshielded wire from the hot-water pressure pump must run too close to the autopilot fluxgate compass-but the implications were anything but. I thought, "If this happens to him every time, I can deduce that the vessel is always on autopilot, there are no manual water pumps, and no one on board suffers a cold shower. More important, the complexity of the boat systems is clearly beyond his grasp."
When it comes to electronic equipment, my own confidence and competence are confined to the borders of the on/off switch, so as I strolled back to Roger Henry, my 36-foot steel cutter, I thought that while the nature of my boat has changed over the years, the nature of nature hasn't. That is, in spite of the added safety and convenience that my burgeoning electronic equipment offers, I'm every bit as exposed as the first Phoenicians or Polynesians to the vagaries of the sea: lightning strikes, flooding, the corrosive effects of salt air. In spite of my pride in having finally plugged into the 21st century, I reluctantly forced myself to repeat it out loud like a litany: "It will break down. It will break down."
That said, I wasn't contemplating some kind of idealistic return to the "good old days." I always look carefully at those little drawings of half-sunken ships on my chart. The beams and bones of failure, they're scenes of abject fear and tragic loss of life. Had any one of those captains been offered a technology that would've pierced the cloak of darkness, predicted the weather, immediately fixed his or her position, or propelled the boat out of harm's way, not a one would have lingered in nostalgia.
Nevertheless, I had to ask myself if the depth of my skills and the redundancy of my equipment mitigated my growing dependency on vulnerable electronics. I decided to take stock: I'd follow every tendril of copper wiring to assess the extent of my electrification project, determine how I'd cope with an electronic failure by either utilizing duplicate or parallel equipment or compensating for the loss in some other way, then decide if I needed to do anything different.
What I Learned First
I was shocked to find myself crawling from stem to stern, from masthead to deep in the bilge. One wire even led to my galley! That solenoid between the LPG tanks and the stove meant that I now depended on 12 volts of uninterrupted direct current to get a cup of piping hot coffee!
Sure I had backups; what sailor doesn't? But did they share any common links? Having a spare alternator and two spare regulators does little good if the problem is the starting motor. Redundancy, then, might be best described as the duplication and separation of functions.
As an example: A sailor's exhaustion at sea inevitably leads to poor judgment, the loss of coordination, and lethargy in the face of essential energetic action. Thus, I believe self-steering equipment to be among the most important on board. With that in mind, I have an Autohelm 4000 ST Tiller Pilot backed up by two spare tiller-drive arms. Recently, this Autohelm developed a deeply disturbed mind of its own and began to steer erratically. Never mind; it can be fixed. Somewhere in the bilge is stored an extra fluxgate compass and a complete control unit. All of which are worthless, however, if the batteries fail. My ungainly old Aries windvane retains its station on the transom, where it does yeoman's work without electricity or complaint. In the unlikely event it should fail, I've worked out a viable sheet-to-tiller arrangement that, if the boat is balanced, can steer a course long enough to free me to tend to other essential chores. As a final fallback plan, I have my Kiwimatic Steering System, otherwise affectionately known as Diana.
Get the Lead Out?
Let's continue on my tour of Roger Henry's electronics.
I have a motor, and I use it too often. But an engine is a chain of a thousand parts, many electronic and sensitive, and the failure of any one can render the whole thing useless. Complete tools and spare parts aside, the best backup is, in a sense, no engine at all-that is, I try to ensure that the boat's design and equipment are such that it can sail itself to safety. This is dependent on a coalition of factors: keeping the boat light, in trim, with low windage, efficient sheeting angles, and crisp sails. It also requires that I keep current my skills for managing the vessel under sail in open and tight quarters.
Once started, a diesel engine will still run even if the charging system fails. That's if the lift pump doesn't require 12 volts. I checked Roger Henry's robust hand pump that lifts fuel from the keel tank to a header tank, which then relies on gravity to feed the engine. My old Golden Hind had a hand-cranked 16-horsepower Volvo that made it completely independent of battery power. I'm still theorizing-perhaps it's fantasizing-on methods to start Roger Henry's larger Perkins 30 without batteries.
On most small vessels, the main engine provides propulsion and generation. Without an outside source of electrical generation, a closed loop results: one that needs the engine to charge the batteries and the batteries to start the engine. Problems can lie within a chain of parts or a chain of events, such as leaving the battery selector switch on "both" while coincidentally leaving a silent but high-amperage implement on.
The "both" position of my selector switch is strictly verboten, and the main breaker is turned off whenever we leave the vessel. (Only the electric bilge pump is wired independently of this switch.) But in the event of a total drain, I have an Air Marine wind generator and a 48-watt solar panel as renewable sources of energy.
Should downflooding wipe that loop out entirely, I carry waterproof 12-volt lithium expedition batteries with an amp capacity sufficient to drive the GPS, VHF, depth sounder, and compass light. Nevertheless, I have manual backups for even those functions. For example, when we were en route to Cape Horn, Roger Henry's depth sounder failed. I wasn't about to let a 20-cent transistor thwart my lifelong sailing dream. For the next six months, Diana and I explored the tortured terrain of the uttermost south with me at the bow swinging my trusty lead line, properly shaped, marked, and armed with tallow, and calling out the readings just like the mariners of old.