Can You See Me?

5 Jul

July 4, 2019/Day 239

Noon Position: 45 18N 58 33W

Course(t)/Speed(kts): ENE 5.5

Miles since departure: 31,472

Leg To Saint John’s

Day 2/Miles 220

Wind is light and variable but is mostly aft, and we’ve been running with the twin headsails for the better part of a day. Not a fast passage, this leg to St John’s, but it’s pleasant sailing.

Except for certain, key equipment failures…

I’ve been wrestling with Mo’s AIS system*–an essential tool for the singlehander–which made every sign of packing it in once we were at sea. In harbor, it passed pre-departure checks by picking up targets aplenty, likely with the aid of the Halifax Coast Guard Radio network. But once we escaped that umbrella, things got strange.

First, my companion boat, Dutch, went off scope yesterday just as she turned for shore, a mere five miles to the northwest, and later a large racing sloop, Challenger, didn’t register until she was within a mile. Then a fishing boat went by with no target on the scope at all.

I tore into the VHF cabinet, checking connections, swapping antennas–to no avail. I called Challenger on VHF as we both ghosted along the coast. No answer.

Frustration. I need things that have functioned well for months to keep doing so. The work list is long enough already.

That night I ran with the radar as my primary watch stander.

On the next day, Mo and I began to pass through a loose fleet of fishing boats working the banks. Now I had a visual on four boats, though only one showed an AIS target. Again, I checked the system’s connections and then tested for signal strength and noise on the line. Nothing out of the ordinary.

As the closest fishing boat made for port, I called on the radio. No answer. Then I called Halifax Coast Guard radio. No answer. (We were 25 miles off shore, so my expectations were low.)

Then, “Moli this is Blaze of Glory.” Loud and clear.

“Blaze of Glory, Moli.”

“You wanted somethin?”

“Yes, I’ve been troubleshooting my AIS system. Do you see me on your scope?”

Pause.

“Yep, there ya’re. A nice bingo. Four miles t’the east.”

“Odd,” I say, “cause I don’t see you.”

Pause.

“Well, that could be cause I had the damned thing off.”

That night we again ran on radar. Fewer than half the fishing boats we passed threw a target, presumably so as to stay invisible to the competition.

Only today, at around noon, did I get confirmation that the AIS system aboard is working normally. We picked up our first ship of this passage on the scope, a strong target at 18 miles to the north.

So, why the mixed signals over the last two days?

For one thing, it’s clear that not everyone in the local fishing fleet cares to be seen. And for another, small vessels, like other sailboats, won’t have nearly the signal strength of a ship, making them harder for Mo to see.**

But it is a relief to tick this problem off the list.

*What is AIS? Short for Automatic Identification System, AIS transmits vessel type, position, speed, course, and other data over VHF radio frequencies, allowing any vessel with an AIS interface to see other vessels with AIS that are within his VHF range.

**Considering that the VHF signal is line-of-sight and projected in a direction (mostly) perpendicular to the antenna, a small vessel moving in a seaway and/or heeled to the wind and with an antenna mounted close to the water (as is Mo’s) will have a much shorter signal range than that of a ship, whose antenna installation is high and whose platform is steady.

This article was syndicated from The Figure 8 Voyage

Comments

  1. Damon Gannon

    Commercial fishing vessels, especially those 65 ft are legally obligated to broadcast AIS data. But when they are at work, they often go dark.

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