Fri Jul 23 2021
We’ve experienced many days of extremely poor visibility on this passage due to dense fog. The frequency of shipping traffic in certain places has been high and in some places zilch. We must have sailed through some imaginary crossroads a few days ago with ships including tankers, container ships, and bulk materials haulers heading West towards some Asian destination or Easterly towards various ports in North or Central America. We’re now in a region where ships traveling to or from Vancouver, Seattle or Portland seem to be moving about. We’ve noted ship speeds generally in the low to high teens.
A ship moving at 15 knots is moving a nautical mile every 4 minutes. Even at our paltry speed limit of 6 knots we’re moving at a nautical mile every 10 minutes. Put us on a collision course and our closure rate is 1 nautical mile at a little under every 3 minutes. In good visibility we might with a good scan of the horizon we might catch site of a ship 8 - 10 miles distant if it’s broadside to us, less so if it’s nearly head on. That implies that our visual detection of a vessel in the best of conditions might give us maybe 25 to 30 minutes to deal with the situation.
Of course with fog, haze, rain, and distractions such as bilge inspections or answering the call of nature we might either be delayed in sighting the vessel until it’s a good bit closer, or just before it impacts us. If we’re under sail a hard turn to port or starboard will certainly affect our method of motive power and we’ll either stall and sails will start to flog or accelerate to a speed that creates a challenging environment if the seas are already lumpy. Stress A + stress B = stress C.
We’ve concluded during this passage that AIS, radar, and an effective radar reflector might be critical to our very survival. In poor visibility we pretty much count on AIS to detect large vessels, but we operate the radar periodically to look for anything AIS might have missed. Recently I’ve been wondering what a ship’s master is to do if the onboard AIS system fails enroute. Perhaps the only requirement is to have it repaired at the next port? In any case, we have detected one ship visually and with radar that was not broadcasting AIS. It was not unnervingly close at 4 miles CPA, but what if it had been bearing down on us in the fog?
On my watch last night I was busily downloading and studying the latest weather, plotting our position versus other yachts in the area and paying attention to the “sail steer” screen on our chart plotter. We’ve had to pay pretty close attention to that screen to anticipate and deal with wind changes that might push us well beyond our 6 knot speed limit. I did get a bit distracted, and suddenly as I was plotting positions on OpenCPN I noted 2 ships that appeared to be traveling together, moving from NE to SW and we were on a collision course. They seemed to have taken no notice of JollyDogs. We were close enough that I elected to make a 40 degree turn to starboard which put us pounding into the seas but at least still sailing. I then hailed the most threatening vessel on VHF ch 16 and asked them if they had our AIS target data and were they observing us on radar? Eventually the watch officer responded yes. I commented to him that I had taken evasive action and was under sail and could not further alter my course, and what were his intentions? Plow straight ahead, apparently. We passed with less than 1 mile separation, and I incrementally adjusted heading to get back on course once I was convinced we were safe.
Next thing I know the lead ship hails the following ship to go to VHF ch 6, then that deck officer begins to complain that the trailing ship is overtaking him, he’s too close, and it’s a big ocean out here and alter your course to give us more room! The overtaking ship watch officer seemed a bit confused but eventually agreed to alter course.
Seriously? Who the hell are they letting drive out here? The janitor?
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