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Reflections on Cruising Instruments

Whether headed over the horizon or around the corner, the right instruments can help keep you out of trouble.
I got involved in a curious conversation with an aspiring young cruiser the other day. He was confused by microchips. I suspect that I am like many other people in these modern times in that even though I probably own hundreds of microchips, I wouldn't recognize one if I had it in my hand. So his confusion is understandable.

The topic was sailing instruments, and he was interested to know which are necessary and which should be considered expensive fluff that a cruiser can happily live without. It seems that the young man had a good head on his shoulders when it came to the value of money and didn't want to part foolishly with his money for unnecessary gear. But he didn't want to scrimp at the expense of putting himself or his boat in danger either.

For highly competitive racing sailors, the answer to this question is moot—the more information disseminated to the largest number of crew, the better. Gaining a few tenths of a second means that every trimmer needs to focus on the VMG repeater or some other bit of information streaming from a computerized data center. Even the casual Wednesday night beer-can racer will want at least the basic performance information.

But what does the true cruiser need? And in what order of importance?

When the young man asked what I would put on my own boat first, I had to think about it for some time. The microchip revolution has changed the whole landscape of sailing and some assumptions have changed forever. Twenty years ago, I would have undoubtedly responded immediately to sink those hard-earned dollars into a good knotlog first. At the time, it was the best tool available for DR navigation, and that was the only kind of navigation we had most of the time.

Having access to position, speed, and depth information can put you in a position to make better decisions underway.
In these days of GPS, however, $89 tells us not only where we are at all times, but how fast we are moving over the ground. For the price, the GPS would now be my No. 1 pick—and I suspect there are few sailors without at least one GPS on board. Since the GPS gives us direction and speed, it knocks the knotlog out of the No. 1 spot clear down to No. 3 on my list.

No. 2 would be a good depth sounder. Some sailors hardly use depth information, which I've always found odd. It not only keeps you out of trouble, but it gives you information regarding the proper anchoring scope. With the addition of upper and lower alarms, a depth sounder can be used to navigate a long inshore passage, and we often use ours this way to run south along the Florida coast inside the Gulf Stream. At 100 feet you're too deep and risk bucking a three-knot current and at 25 feet you're too shallow and risk running aground. Love those alarms.

We sometimes use depth information for "quickie" navigation rather than plot GPS coordinates on the chart. Just take the information from the depth-sounder display, locate the same depth pattern on the chart, and you have a pretty good idea where you are.

Contemporary iterations of the leadline (like Maptech's Contour Professional) assist immeasurably in the quest to answer that all-important questionhow much water is beneath the keel?
Most depth sounders today are fitted with water temperature as a side bonus. We have found this useful only on a few occasions—finding the walls of a major current and seeing if the water is warm enough for a dip.

In third place, I would insert the knotlog back into the picture. So if we have speed on the GPS, why would I want to spend another $500 and have another hole in the hull just for a second way of guaging speed, you ask. Good question. The two speeds are different, and that difference creates a navigational opportunity. The GPS measures speed over the ground while the knotlog calculates speed through the water. Assuming that both are properly calibrated, the difference makes it possible to vector current speed and direction.

The knotlog also makes "quickie" navigation easier and has uses when logging in. Besides, it gives bragging rights to the bored night crew who watches its little numbers flash by, looking for the best speed. Seriously, it gives even the cruiser a good idea whether changes in sail trim or steering angle are beneficial or detrimental to performance. This can shave many hours of time off a long passage by helping you to squeeze the best speed out of the boat.

If the kitty can withstand the strain, radar, chartplotter, and wind-direction instruments also have their place on the cruising vessel.
There is no doubt that these three instruments can get you anywhere in the world you want to sail. If there are still another thousand dollars or a little more in the equipment budget, there are still some useful instruments available to make life easier. But choosing fourth place is the divide between wind instruments for the performance cruiser and radar for the cruising navigator.

There was a time when wind direction instruments and wind speed instruments were two distinct units. And there was a time when I laughed at both of them. But many modern cruising boats have very complete and sophisticated dodger and bimini systems that make seeing a masthead-mounted wind arrow impossible, and these protective devices also mask the true strength of the wind.

There are those sailors who simply have to know how hard the wind is blowing to the exact knot. They memorize the wind ranges on each sail and a few have little numbers on the roller-furling line to match with their wind meter. To my taste in sailing, I found that even the Beaufort wind scale presented too many categories, so I invented the Wood Wind Scale for Non-performance Cruisers that looks like this:

"Many cruisers with wind speed and direction instruments on their boats claim that once it's in front of you, the tendency is to become more performance-minded, making faster passages as a result. "
1- Not enough wind to sail; turn on the engine.

2- Beautiful day for a sail.

3- Time to reef.

4- It's too damn rough out here; let's look for shelter.

When you use this scale, you have no need for wind speed, but since it comes rolled in a package with wind direction, you may end up with it anyway. Many cruisers with wind speed and direction instruments on their boats claim that once it's in front of you, the tendency is to become more performance-minded, making faster passages as a result.

That may be true. But with that extra equipment budget and my rather lackadaisical attitude toward performance, I'd rather have radar. Radar is not only a safety and collision-avoidance tool. It can be used to spot and avoid the worst of thunderstorms and squall lines. It gives comfort and peace-of-mind in fog, rain, and reduced visibility. Radar serves as another navigational tool, extending your eyes to find buoys before the binoculars can locate them, and makes entering a strange port at night much safer. The lights of businesses, condos, and highways along some shores have become so intense that finding nav aids when coming in from sea is almost impossible.

So, my personal choice for the No. 4 spot would be a small radar set. If there was still money left in the budget, I'd probably put the wind instrument set in at No. 5.

On high-performance cruisers, the level of instrumentation may need to be ratcheted up several models for the boat to reach its full potential.
My new young friend asked me about repeaters and I had to admit that I had never owned one. Racers, of course, need information at hand for the helmsperson, navigator, tactician, and the trimmers. But for cruising, most of the information is needed only at the helm. I acknowledge that logging out at the end of a watch sometimes involves a few trips from the helm to the nav table or having your mate call out the numbers for you to write down, but the extra few minutes of work was never enough for me to spring the cash for a set of repeaters at the chart table.

When I think of cruising, I automatically think of somewhat restrictive budgets. I realize that a new breed of cruiser is coming on the scene, armed with buckets of dollars and a desire for the latest technology. If you are one of these, disregard everything you have read above about budgeting and buy at least one of everything. Then add a laptop with computerized navigation software, a color chart plotter, and interface everything into the autopilot. In a few years, it may be possible to automate the boat to sail herself entirely so that these sailors can stay in the comfort of their house and watch the cruise on their webcam.

Tom Wood is offline  
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