On the road again

I am happy to report that at 2pm this afternoon Sans Souci departed Newport Beach headed to Seattle. Arrival is expected sometime on Saturday.


Weather for the next two days looks great!


Mon/27: NW-NNW 12-18kts, waves 2-3ft. Swells NW-WNW 4-6ft, could reach as high as 7ft during the day with a long period 13-15sec.

Tue/28: NW-N 10-17kts, waves 2-4ft. Swells WNW-NW 4-6ft, could be 7ft with long period 13-15sec. Winds seas tending to ease 05-12kts with waves closer to 1-3ft and WNW-NNW swells 4-6ft, lowering to possibly 3-5ft during Tue/night.

Shortly after leaving port, Jeff blindsided me with the following email:



Ken: Things are going good and the weather is good. I was thinking maybe you might want to fly out to Port Angeles when I am coming in and ride into Seattle? Kenmorfe has a daily flights into Port Angeles. That will be on Friday I hope , you have time to think about it.






I hadn’t thought about doing any portion of the run, but it sure is tempting. I have some schedule conflicts .. but, will see if I can clear them. It would be a blast! Counting the time to get through the locks, it would be about a 14 hour run. We’ll see…


On a different topic:


The big topic today on the “Passagemaking Under Power” (PUP) discussion forum has been to comparative advantages and disadvantages of Arpa and AIS.


Arpa is a technology on high-end radars that intelligently tracks targets on the radar. By analyzing the relative position of the “blobs” on the radar, the direction, and speed of the object can be determined. The reliability of Arpa varies with the quality, and clutter of the radar image. When two boats are close to each other, or when high waves, birds, squalls, etc muddy the image, Arpa can easily become confused. On many occasions, I’ve watched Arpa become confused while tracking a boat, and suddenly shift to tracking a wave instead of the boat. Generally though, Arpa works flawlessly, and is an extremely valuable tool. For any object on radar, Arpa can report to you not only its’ speed and direction, but also whether or not you are on a collision path, plus how soon, and exactly how close, you’ll come to each other.


AIS is a technology that works independent of radar. AIS comes in two versions; receive only, and transmit/receive. A boat equipped with an AIS transmitter transmits its’ position continuously. Depending on the quality of the AIS unit a great deal of other information is also transmitted: speed, heading, name of the boat, information about the type of boat (length, beam, depth), as well as where the boat is coming from, where it is going, and even what cargo it is carrying. Large boats are required to have AIS (I forget the minimum size). Because of the cost of installing AIS, generally speaking, small boats have no AIS, or an AIS receiver only. Whereas most larger boats (over 65’) all have AIS that is both transmit and receive. Prices are falling quickly on the AIS transmitters/receivers, and as prices fall, the percentage of boats with transmitters is rising rapidly.


Both AIS and Arpa provide speed and heading to surrounding boats. With this information the “Closest point of approach” can be computed, warning you about potential collisions.


The extra information provided by AIS (besides speed and heading) comes in handy. I have tried in the past to contact freighters via VHF radio, and had almost no luck getting a response. When using AIS data, I can instead contact them by name. This little extra touch in radio communications seems to make a huge difference.


The debate on the PUP board revolved around a few points: Are they worth the money? Which is better? And, what happens when the cost of AIS transmit/receive units far enough that the majority of boats have one.


As usual, I have a strong opinion on this topic:


Anyone who can afford an Arpa, or a transmit/receive AIS, should have one. Each has limitations, and the best is to have both. Arpa doesn’t work when the radar doesn’t have a clean image, and too few boats have AIS for it to be relied on. I just don’t think that you can have too much information when at sea.


Even if the price for AIS, which gives much more information than Arpa, were to fall to nothing, there would still be a place for Arpa. Here’s why: the best thing about Arpa is that, other than weather interference, it is 100% under your control. The other boat doesn’t need to have any kind of equipment. I have seen too many sailboats and pangas running offshore, at night, with no lights, to ever believe there can be a world where we can depend on everyone having AIS.


Not all AIS units have the ability to transmit your position. There are very inexpensive units that are “receive only”. They tell you where the big boats are, but don’t tell them where you are. My only comment on these is that if you can’t afford a unit which also transmits your position, then a receive-only unit is better than nothing. I like the transmit units because they tell other boats how to avoid hitting me. When we were running south along Baja last year, I had a cruise ship a few miles in front of me, on a direct collision course. I radioed to the cruise ship to ask how we should pass each other, and he responded that he had already altered course and that I should hold course for a close passage. At the time I was with a fleet of about nine other boats, with limited ability to move. Without AIS I don’t know how we could easily have managed it safely.


And, as I mentioned earlier, there are those who don’t like the idea of all boats having AIS transmitters. Currently, most of what appears on AIS is commercial traffic. If all boats appeared, the nav screens of freighters in busy ports would be littered with 100s of little boats. My sense of the attitude of these big freighters is that the little guys have to fend for themselves. The freighters are not very maneuverable. If a small boat finds itself a few hundred yards in front of a tanker, regardless of what the rules of the road might be, the small boat needs to move, or prepare for a collision. One wouldn’t think the big freighters move very fast, but they are often moving 20 to 30 knots, and can come at you much faster than expected. I generally give them a very wide berth, and when there is doubt, I am on the radio with them five miles or more in advance.


There is talk that if all boats get AIS, that the freighters would use software on their radars to “filter out” all the little guys. Whereas this may or may not be true, I see it as irrelevant to the discussion of the benefit of all boats having AIS. When I am moving in limited visibility conditions (night, squalls, high seas, fog) I can’t imagine a boat I wouldn’t want to know about. If there are squalls or high seas, my radar may be useless. AIS is not affected by either of these conditions. I can’t imagine me ever saying “I have too many targets on radar. Turn on some filters and make them go away.” That said, I can see that it would be handy to momentarily be able to see only the freighter traffic. These giant beasts move quickly and I am constantly surprised by how tricky it can be to stay out of their path.


So.. in summary: Electronics on boats are getting cheaper rapidly. When we crossed the Atlantic in 2004, one of the boats in our fleet had the first AIS unit I had ever heard of or seen (An N57 – Goleen). My recollection is that he paid around $25,000 for it. Today, full transmit/receive systems are easily found for under $5,000. Within a few years another zero will drop off the price, and these will be a reality on all boats. Arpa is now available on almost all radars sold. I am a fan of both, and use both at all times while at sea. These things add enormously to safety at sea, and I can’t imagine that ever being a bad thing.


-Ken W


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