Offshore Log: Still In Class
Feedback on our October 1 column gives us a chance to stay in school and dig deeper into the same topic.
by Nick Nicholson
It's not unusual for a Practical Sailor article to generate a fair amount of reader response. This is particularly true when we either get on our soapbox or venture far out on a fragile limb, both of which we do on a regular basis.
"Back to School," the Offshore Log in the October 1 issue, generated an unusual number of responses from professional navigators: those who are involved in teaching navigation and seamanship, those who have had careers as navigators in the military, and those who are regular navigators of racing yachts. Some of our correspondents asked to reprint the article to hand out to their classes, commending it for its emphasis on the fact that traditional piloting skills still have an important role in an age when many sailors don't even bother to learn them.
This was, in fact, the purpose of the article. With today's staggering array of marine electronics, a frightening number of sailors have lost the habit of maintaining even the most basic piloting skills, such as plotting courses and making corrections for current set and drift.
The one strongly negative letter we received deserves special attention. The writer, a former navigator of a US Navy fast frigate—as well as a first-in-class graduate at the navy's Piloting and Navigation School—took virtually every aspect of the article to task. He brought up a number of valid points that deserve attention. We will quote extensively from his letter to bring his concerns to the attention of readers. We will also offer our own comments on his observations.
Here beginneth the lesson, with the letter from Bruce A. Cauley, former surface warfare officer. The letter has been edited for space, but with no change to the details of the message.
"First, piloting techniques are based on line-of-sight and dead reckoning (an estimated rather than a known measure of one's position).When you are unable to determine your position in limited visibility or in areas of known hazards you should heave to, anchor, or seek open water. If the captain and navigator know that there are hazards to navigation in close proximity to the vessel's rhumb line, are not sure of their position, and do not have good visual lines of position, then the prudent mariner ceases leading his vessel towards harm's way. Period.
"Second, the rules of navigation require that a vessel under way in limited visibility sound signals and slow to a speed that will allow the vessel to take appropriate action to avoid hitting another vessel once that vessel is seen coming out of the mist. And, since you knew full well that radar is ineffective at seeing small boats (especially radar units on small boats such as sailing yachts), you knew that you were taking your crew and vessel into harm's way.
"Third, to determine an estimated position from a DR plot on a small vessel, the navigator must observe the steering actions of the helmsman in order to determine if the helmsman is steering above the given course or below it. DR is totally based on a predetermined course that is given to the helmsman. However, the helmsman will steer the boat to maintain boat speed and sail trim. This will make the DR almost irrelevant unless the navigator is keeping a watchful eye on the steering compass over the helmsman's shoulder. The navigator cannot keep his eye on the radar screen all night or for the entire watch and have a good idea of what is going on in the real world above. If the boat is going so fast that you are unable to keep an accurate plot and check the helm, then you are going too fast to be safe.
"Fourth, as you stated in your article, your radar did not pick up the fishing boat until it was far too late. Guess what? It won't pick up anything close when the weather gets nasty. You cannot confidently rely upon radar in a small boat to give you adequate warning and protect you from other boats.
"Fifth, without your electronic aids, your '…paper chart, straight edge, and pencil' would not have saved you in the waters of Halifax. It would not have taken very long for you to have been practically lost, i.e, sufficiently lost to get into trouble. The point? Don’t go sailing at night or in low visibility if you have to rely upon the full suite of aids. It was obvious that if you had completely lost electronics your piloting skills would have not kept you and your crew out of harm's way.
"There is no good excuse to take a vessel into harm's way. A sailboat race is an especially poor excuse to risk the lives of your crew. The tale you told was of recklessness for no good reason. Someone of your experience should know better. You would have been better off recommending in your article that readers read Chapman's from cover to cover, followed by Bowditch [American Practical Navigator]. And then, recommend that they stay in port in bad visibility."
Dogmatic solutions to any question of navigation or seamanship may be the right answer on the test, but the context of the problem must be considered. Certainly, a primary goal should be to minimize the risk to the boat and crew. That may mean a course of action that is not immediately obvious and which may be counterintuitive.
Take, for example, the option of heaving to in limited visibility. When you stop the boat, you put it at the mercy of currents and other outside influences that may introduce an even higher level of uncertainty in your position than may already exist. This is particularly true in areas of strong tidal currents such as the coasts of Maine and Nova Scotia. It may also expose you to worse weather that may be headed your way.
Anchoring may or may not be a viable alternative. Anchoring in a channel or traffic lane (or in a large fleet of racing boats under full sail) in limited visibility may expose a boat to risk of collision from another vessel under way. The primary sound signal for a vessel at anchor in limited visibility—ringing the ship's bell for five seconds at one minute intervals—is notoriously difficult to hear from a vessel under way.
If you can't be certain that the place in which you are anchoring is out of the way of potential traffic, anchoring may be risky.
Heading towards open water may or may not be a good solution. It may require a substantial change of course. If in heading towards open water a sailboat must change course from a reach or run to a beat, position uncertainty may be dramatically increased, even if you keep an accurate record of boatspeed, course, and time on each leg of the beat. Leeway when reaching and running is negligible, but is likely to be significant in beating, even in flat water. Beating upwind also means steering to the wind rather than the compass, and here, as Mr. Cauley correctly points out, differences in steering habits can introduce sizeable errors into the DR course.
Our loss of position information from the GPS was transient. Because we use a variety of navigation tools, the loss of a single navigation input, even one as critical as the position information, did not have to bring a stop to our racing. Had we lost more inputs—complete electrical failure, for example—our course of action would have been different.
A navigator must adapt to the situation at hand, and be prepared to deviate from his plan according to changes in the navigational context.
This is a legitimate concern, one which was mentioned by two other letter writers. At night, particularly, it is difficult to gauge the range of visibility, and to determine at what point "restricted visibility" exists and sound signals are appropriate.
During the Halifax Race, our time of least visibility was in Halifax Approaches. This is not unusual, and is one reason for the existence of a traffic control system in those waters. It was late at night. There had been a fair amount of radio traffic between other vessels under way earlier, but it had quieted down, as no one who was not already under way was leaving or entering, given the visibility.
As required by the sailing instructions, I had contacted Halifax Traffic and reported my position, which they acknowledged. They also notified me of the only other traffic in the area, a ship which I quickly determined not to be a threat.There is no doubt that in those conditions, going by the rules, we should have been making sound signals, but on the final approach, we did not. Areas with a lot of fog have a lot of sound buoys, and Halifax is no exception. Blasting a horn affects the hearing of the crew, even after the signal is made. Under the circumstances, I felt it was important for the crew to maintain maximum hearing acuity to identify the aids to navigation that we could not see, but should hear.
If there had been any reason to believe that there might be other traffic in our area, the priorities would have been different.
In the approaches, I kept a dual radio watch on VHF 16 and 12 (Halifax Traffic) in case any other vessel suddenly turned up.
This is an important point. Knowing how the helmsman is actually steering compared to the course he or she is supposed to be steering is critical to correcting the DR.
Like most experienced racing navigators, I keep a "form book" on every regular helmsman who sails with us. I know, for example, that one of our drivers is obsessed with sailing the boat as close to the wind as possible when beating, while another—equally experienced and successful—will foot the boat several degrees and sail faster.
Their courses through the water may vary by as much as four degrees, even when it is not possible to distinguish differences in VMG. When sailing upwind, I can usually tell who's steering without looking just by watching the true wind angle on the instruments belowdecks for a minute or so.
This is not as good as looking over someone's shoulder while they're steering, but as Mr. Cauley points out, it's not possible to keep a good radar watch and keep a constant watch on the helmsman at the same time.
I also run background strip charts on the computer of any number of variables while racing, including course steered. The course steered strip chart, as an example, has time on one axis and course steered on the other, and is used as irrefutable proof of who steers the straightest course when the helmsmen question each other's skills, as they do on a regular basis. The form book—developed over more than a decade of sailing with the same crew—is a valuable tool, with or without instrument backup.
Radar is only as good as its operator. Getting familiar with your radar in good weather, when you can compare what's really outside the boat with what you see on the screen, is critical.
In the Halifax race, I had already seen some of the limits of the 1700 series Furuno radar we were using, thanks to our close encounter with a fishing vessel offshore during daylight hours. Because of the relatively flat sea state, I detuned the sea clutter function to accentuate targets close to the boat, and brought the gain up as high as possible without clouding the screen with excess returns. I also toggled between ranges to get a feel for whether or not a specific return was real, or just clutter. We also leveled the scanner to avoid shooting directly into the sky and sea—an important refinement.
I had no illusions that the radar would show every target in a timely fashion, and the crew on deck were alert to the fact that it was their duty to keep a sharp lookout. I have rarely seen as attentive a crew as we had in the final hours of this race, while visibility was deteriorating.
The approach to Halifax Harbor from the southwest is a classic: a nasty set of reefs and rocks along your left hand as you approach from offshore, and a fairly wide open fairway on your right hand. The reefs and rocks are well marked with a series of buoys which constitute marks of the course that must be left on the proper hand for racing purposes as well as safety. The shortest distance to the finish would have you nail several of those marks straight on, which I was unwilling to do in the limited visibility.
Instead, I offset our course slightly to leave hazards to one side of the vessel, in effect creating a cushion that would reduce ambiguity when searching for a specific aid to navigation in case the instruments went down. This is pretty standard practice for most navigators in such a situation.
And yes, we did slow the boat down slightly on our final approach. The last few miles to the finish were a dead run—not the fastest point of sail for any boat. Sailing optimally would have meant two jibes to the finish—no big deal, normally, even in the dark. Instead, we bit the bullet and sailed dead downwind towards the finishing mark, reducing the potential for navigation error.
Missing the short finishing line in the fog would have cost us a lot more time than sailing more slowly directly at the mark. These are the types of trade-offs that you learn to make when racing. I had cost the same skipper an important race a decade before by overstanding a mark in zero visibility, and was not about to repeat that mistake.
Sailboat racing is an inherently risky undertaking. Looking at the best ocean racers as role models for good seamanship is the equivalent of watching Michael Shumacher to learn how to drive a car safely. The difference is that in sailboat racing, we sail among all the other traffic on the ocean, sort of like driving your Ferrari F1 down Interstate 95.
As ocean racers, we constantly walk the tightrope stretched between the devil (high performance at all costs) and the deep blue sea (good seamanship).I would point out that in many sports—auto racing and mountain climbing, as obvious examples—the element of risk is not only there, but is part of the attraction to the sport. You might define offshore sailboat racing as an exercise in bad seamanship, conducted as quickly as possible. Whether it's a good excuse for risking your life is a matter of individual judgment.
Mr. Cauley's recommendation that we read Chapman's (Chapman Piloting & Seamanship) and Bowditch (The American Practical Navigator) from cover to cover is brilliant advice. My own 1977 edition of Bowditch has sailed with me over some 50,000 miles of blue water. Moldy, dog-eared, and heavily underlined, I love it dearly.
A few words from the introduction to Chapter XXIII ("The Practice of Marine Navigation") in the 1977 Bowditch will sum it all up pretty well. Remember, these words were written before the days of pinpoint position-finding with GPS.
"…The most important element of successful navigation… cannot be acquired from any book or instructor. The science of navigation can be taught, but the art of navigation must be acquired. Modern navigation is a blending of the two—a scientific art. The truly successful navigator is one who supplements his knowledge with judgment, utilizing every opportunity to improve his judgment through experience… The navigator cannot expect to be fully reliable unless he is alert, constantly evaluating the situation as it develops, avoiding dangerous situations before they arise, or recognizing them if they do occur, and always keeping 'ahead of the vessel.' …It is not wise to attempt to reduce navigation to a series of steps that can be followed mechanically. The methods and techniques to be used are those which are applicable to the type of vessel, the equipment available, the training and experience of the navigator and any assistants, the local situation, etc....It is important that a navigator make an 'estimate of the situation' and use methods and techniques that are best adapted to the conditions at hand…"
While we would not recommend that people deliberately go out in fog to learn what it feels like, getting caught out in limited visibility is a normal part of sailing, especially in New England or Nova Scotia.
We asked several experienced racing yacht navigators who are also retired US Navy or Coast Guard officers how they resolved conflicts between their training in navigation and seamanship and their sailboat racing, and how their military training in navigation helped or hurt them as racing navigators. Here some comments from CDR John Brooks, USCG retired, former CO of the buoy tender Redwood, former head of the Coast Guard Academy's sailing program, and instructor in navigation at the US Coast Guard Academy. John is also a successful racing yacht navigator, and is in fact the best navigator we have ever sailed with.
"While I can't speak for Annapolis [the US Naval Academy], navigation instruction at the Coast Guard Academy stresses the basics of DR and piloting prior to anything else. In the pre-GPS era, this gave me a real advantage as a yacht racing navigator, since I could determine set and drift and come up with a steering compass course much quicker than most out there. I recall sailing through Plum Gut in the fog at speed during Block Island races (including on Coast Guard Academy yachts), and similar situations during Halifax and Gulf of Maine races.
"On the Coast Guard ships I have been stationed on, there have been many times (pre-GPS) when you could not get a really accurate fix in the Caribbean and the Bahamas, but you never went to "all-stop" because you hadn't had a fix in three minutes.
"Navigating the buoy tender Redwood in the Connecticut and Mystic Rivers was similar, in that electronic fixes were not accurate enough to keep you in the channel. Even if you had objects with good horizontal control from which to shoot bearings, by the time you got the fix plotted, it would be too late to take corrective action based on that fix.
"It's easy to think of some real-life examples of routine events that don't fit the military model [in terms of navigation protocols in limited visibility]: ferry traffic in all weathers and visibilities, including high-speed ferries between Pt. Judith and Block Island (RI); the catamaran ferry from Bar Harbor (Maine) to Yarmouth (Nova Scotia) [which travels at 40 knots in any visibility]; big-ship traffic worldwide (English Channel, Elbe River); the Rhine River (Germany), with up to five abreast in two different directions in 5+ knots of current.
"I thought the article was right on point. It's amazing how many boats are 'lost' without their wayfinding electronics, since fewer yachties seem to know how to navigate these days."
To return to the point of the October 1 article, we would never for a moment suggest that you abandon modern electronics. Nor do we suggest ignoring the basics of seamanship by careening blindly through fog at high speed just to prove you can do it.
What we are saying is that if you practice traditional skills—that is, the way sailors did things before GPS, chartplotters, and the other aids we take for granted—you will not be helpless when your electronics go on strike. And we'll keep saying it.