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White-knuckle passages now routine
Glass helm further refines chart-plotter navigation
By Brooke Williams
Fog! Okay, can’t be too bad. Activate the fog signal. Fog should burn off in a couple hours when the sun gets higher. Only the fog never did burn off, and we were crossing New York shipping lanes, transiting from Cape May, N.J. to Newport, R.I. What to do? Actually not much that should not have already been done well before encountering fog.
Fog can occur pretty much anywhere, anytime. New England waters are particularly susceptible to fog early in the summer because of significant differences in air and water temperatures. In this case, temperature forecasts for the entire Northeast were high 80s and low 90s. Our water temperatures were barely 60. As the air heated up, fog blanketed waters from New Jersey to north of Cape Cod for 24 hours, leaving us to run all day in fog and to make our landfall in zero visibility.
The good news is that one does not need to see to know what is going on around the boat. Commercial vessels and pleasure craft issue VHF Securite warnings providing their location, course and speed and general intentions. Vessels in close proximity talk to each other to confirm position and movement. Radar identifies who is close and confirms GPS position when close to land. GPS & chart plotters provide accurate position information so one knows when approaching shipping lanes. Running in the fog requires a different kind of concentration and patience. Admittedly, patience can be hard to maintain when blindness seems to demand anxiety.
What worked for us? What can you expect? We found that keeping a note pad handy was important so we could write down geographic information when vessels issued Securites. Our radar has our GPS signal built in so we could get a contact Lat/Lon with the radar cursor. We talked with a barge by calling the vessel at a particular position. Other vessels did the same. Be prepared to find and talk with vessels around you. By listening to conversations between an outbound tanker and sport fish boats, we were able to identify the tanker on radar and cross his shipping lane about 2 miles behind him without worry. We did issue our own Securite when we made our approach to Narragansett Bay.
Radar was, of course, essential. We had spent time getting used our new boat’s radar/plotter system so felt comfortable relying on it as our eyes. Radar requires interpretation so need to use it regularly under varying conditions when good visibility can confirm what it is or is not picking up. Any tuning adjustments (gain and particularly alignment) need to be done at these times. Zero visibility fog is no time to worry about proper setup.
Our radar and GPS plot are on side-by-side computer screens so we could easily compare images. Nobeltec transfers a cursor image from one to the other so identifying a radar blip puts a corresponding mark on the chart. (Use Course Up feature of plotter to get accurate positioning of targets). The radar’s MARPA capabilities meant that the contact was constantly plotted on the chart. We found MARPA calculations of contacts’ course and speed not helpful as the values bounced all over the place.
More useful was the plot. Seeing an image in a shipping lane near where the tanker last reported helped us to conclude we were in no danger of getting run over. Off Point Judith after midnight we encountered the usual fishing boat activity. One contact appeared to be heading on a collision course with us. However, its plotter mark indicated if that were the case the vessel would be headed straight for rocks on the other side of us. Knowing this encouraged patience and soon enough the contact drifted off.
I have had extensive at sea experience some in serious fog as a junior officer driving a cruiser for the Navy. Dee has had some radar fog experience from our sailing days here in New England. She found that hitting the fog in the daylight was lees anxiety inducing than had we hit fog ant night. By the time night settled in she was comfortable with our systems.
We spent some time dodging the fishing fleet off Point Judith without getting nervous. By that time we had long since confirmed the accuracy of our information. We both did get nervous when we made our passage into Narragansett Bay. I guess we have spent too much time making this approach in heavy traffic and were too aware that whatever we hit would be another vessel or rock. Anxiety unnecessary – fog had lifted a bit in the harbor. We could see enough around us to recognize we were safely home. A long, tiring day—20 hours in the fog.
We have ordered Nobeltec’s AIS module because we will often be outside or in commercial shipping lanes. Commercial vessels are now required to put out an internationally recognized Automatic Identifications Systems (AIS) VHF signal. AIS requires dedicated equipment to send or receive. Information provided includes vessel identification, location and course and & speed. Pleasure craft may have a broadcast and receive systems but more likely would want a receiver.
Nobeltec has recently introduced a black box receiver that integrates the AIS signal with its computer based programs. Their software will plot the sending vessel on our chart with broadcast information. This will be a great improvement over noting position and looking for the target on radar and then making a judgment call about what that target really is. Some electronics manufacturers require stand-alone receiver/displays that don’t integrate with chart plotters—yet another reason we were convinced that computer based systems are the best practical approach to pleasure boat electronics.
In retrospect, we appear to be well prepared for fog and certainly better off for the experience. I have been asked to recount our experience so please do not take this piece as a primer on fog. I suggest that those interested in preparing for fog seek out tracts that could be considered authoritative and figure out what you should do that is better than what we did. For example, can you run time and distance dead reckoning if systems fail? Many years ago my father-in-law made a similar fog run into Newport with no radar, no Loran or GPS – just charts and his DR abilities. I don’t think I could.
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