Icecapades

OK – I have been remiss. I am jumping ahead a bit to Antarctica – Iron Lady’s latest adventure. Will be doing lots of different posts on the Peninsula (including the Drake, Horn and Patagonian Chile), but for starters I thought I would do one on ice – and there was a lot – and how we dealt with it.

Ice was a fact of life during our three weeks there. It was essentially every where, but in open water, we generally did not see more then 4/10 coverage so we could navigate around it. That was when we could see it (read fog, wind, denser ice, and glare) but that is the subject of another post. This one is about ice in our anchorages.

Almost every anchorage had a glacier attached to it. Deception Island didn’t but it had other issues like high winds and poor holding in volcanic ash. Again the subject of another post.

The glaciers had a habit of calving during the high summer during our visit. Having said that, high summer air temps were right around 0 C – just about the same as the water. So the reality was that ice that calved from the glaciers really didn’t melt much. As such, they were more or less our constant companion while at anchor.

That necessitated dedicated ice watches. While I have managed without a stabilizer fin, damage to a rudder or prop down here would be really, really bad. Ice watches, however,, were really just the beginning of what we learned during out time there. It gradually evolved into a complete strategy. Having said that, you are NEVER completely safe. Fellow Antarctic cruisers we talked to along the way talked about being trapped for weeks or longer when things went bump in the night and the ice was against them. Even in Antarctic summer.

I will also admit that I was unprepared as I did not understand the full scale and scope of what we would have to deal with. Fortunately, Iron Lady was up to the task and we were well equipped. We also had the benefit of Grey Wolf’s (78-2) experience from a prior trip down.

Our first encounter began soon after we arrived. A quote from my personal log. “Off to bed early but the sound of the engines coming to life woke me up around 0100. Looking out the port light, the view was unfamiliar. Instead of the penguin colony, I now see the sand spit that guarded the harbor – and lots of ice – big and potentially damaging ice. Lots of activity aboard Grey Wolf as well as I came on deck.”

The rest of the night was spent fending off ice. Went back to bed but the wind changed and all the ice that was piled on the lee shore came back at us. Engines were started and we were chased out of the harbor by ice at 0600. Another sleepless night which was to become the norm in Antarctica.

With ice so pervasive, we gradually developed strategies to deal with it as best we could.

We started to raft Grey Wolf and Iron Lady together when weather would permit. The procedure was for (generally) Grey Wolf to pull into an anchorage and drop her hook. Once settled, we would put out large fenders and pull along side. Two great benefits to doing this – we could step from one boat to the other to socialize – and we could share night ice watches to let folks get more sleep.

But I am a bit ahead of myself. The charts (both electronic and paper) down here ranged from awful to nearly useless. They were inaccurate with respect to the actual positions of land masses and they frequently lacked any useful soundings. In many cases, we had tracks from other boats which were invaluable. Good reason to take time to talk to all you meet enroute – they are an EXTREMELY valuable resource.

We also used our radars to advantage. The big Furuno was really valuable for navigation and detecting ice.

Our small Furuno 5G radar was really valuable for assessing anchorages among other things which I will get to. We would send out our large dink (Beer Can – so named by our kids). We would set up an ARPA target on it and Jim would run a 5 meter contour on the way in to an anchorage so we had a safe working depth contour.

As the boat (or boats) would head into an anchorage, we would use the contour line established by the dink track to guide us. The additional safety measure would be our Furuno under water scanning sonar which we would use to look for obstacles on the way in or at anchor by doing a 360 degree scan.

Once at anchor, we would also use our 5G radar to set up a guard zone to alert of iceberg intrusions. While that was helpful, it was no substitute for overnight ice watches.

We would also use the 5G radar to track larger bergs so we would know when they posed a danger- and there were lots.

The following pic shows our 5G radar tracking a berg that came out of a side channel and honed in on us like it was laser guided. You can see that it passed directly down the heart of our swing radius. You can also see from the size of the radar return that the above water portion was about the size of Grey Wolf, and that was just the above water portion. Remember that the under water portion of an iceberg is roughly 3 times the above water portion.

The following is a pic of the actual berg.

Beyond the passive stuff, were the ice poles that we used to push surprisingly large bergs away. Our daughter, Kim, became the resident ice pole expert.

We also gradually learned to use the engines to maneuver out of the way of bergs even while at anchor. The boat thruster became an effective tool to push bergs away.

We also used all of our larger tenders as tugboats to lasso, drag, and push surprisingly large bergs away.

We also found that our floating 3/4 inch poly shore lines were useful. We would float one between the bows of the boats to prevent any bits from getting caught between the boats when they were rafted together.

We also would stretch a line across the anchorage and use it as a boom to capture ice. It did a remarkably good job, and with some luck, the ice bits would all move on with a change of wind and tide.

More next time.