Friday, June 01, 2018

Passage to the Tuamotus

[Kyle]From the Gambiers a big weather system was forecast to be passing south of us. Its influence was expected to overpower the trade winds and reverse them for the foreseeable future (bad for us). Before that happened, we had about four days of easterlies left, five if we went further north. We can take a hint. We were off to the northwest to the Tuamotus. We decided to head off and make the five day passage to Hao.

There are lots of islands in the southeast Tuamotus between the Gambiers and Hao, but few with anything other than open roadstead anchorages. Many islands get their supplies by launching canoes off the beach while the supply ship loiters nearby. We didn’t fancy being stuck at one of these waiting for the trade winds to return, so we pressed on to Hao.

Hao has an enormous lagoon with a pass. The French Navy used it as a base during all of the nuclear testing it did down here. They’re gone now, but the village is the largest in the Tuamotus, so we were hoping for a couple of decent stores and maybe even some internet.

A great sail
Kyle still found some things to fix on the way

The passage was uneventful, apart from having to watch out for the above mentioned islands. We are simultaneously completely comfortable with and rapidly becoming a little overdosed on always being on multi-day passages. On arrival at Hao we had been at sea for 43 of the last 63 days. We were ready to be there, but at the same time, five days felt like we were just getting warmed up. The lights of the village appeared and we hove-to until daylight to enter the pass.

That was exciting. Our first sign of trouble came when I spent my night watch watching a freighter enter the pass on our AIS display. I’m sure they have done this a thousand times, so they’ve figured out where the coral bommies are. I’m sure the Navy did it all of the time.

The part that concerned me was their speed. All of my careful calculations said that they should be fighting a pretty big current going in. Instead, they seemed to be getting a bit of a boost.

Entering the pass

Currents in the passes in the Tuamotus are notoriously hard to predict. It starts with the tide. At high tide, water flows in the pass. At low tide, it flows out. That’s the theory, but each lagoon is different. Most have relatively porous rims, so waves are always sloshing water over the coral into the lagoon, which then exits via the deep passes. Big waves and fewer tall islands means more water gets in. Fewer deep passes means more current at each one. Orientation also means a lot. Some atolls fill up when the waves come from the east, others from the west. It is not uncommon for the passes at two adjacent atolls to have water in their passes going in completely opposite directions. The only real way to know is to ask a local, preferably a dive shop, or spend a couple of days watching it yourself. Navionics, the charts we use on our chartplotter, only gives tides for a couple locations in the Tuamotus and even those seem to be calculated rectally, so mostly I calculate it using lunar transit times with corrections for wind direction and wave height. I’m right more often than not, but every now and then, I find that I’m 180 degrees off.

Hao is the third largest atoll in the world behind Rangiroa and Fakarava. Unlike those two, however, Hao only has one pass and as such it, often has no current flowing into it. I factored all of this in when I figured out the supply ship should be bucking the current. It looked like I was going to be way off again.

As we approached the pass, I had a look through the binoculars and saw that it was smooth and flat. I wasn’t expecting that for an hour or so, so we hurried over while the getting was good. By the time we made it, little eddies were starting to swirl ahead of us and standing waves were approaching from astern.

The eddies and the standing waves both grew more boisterous. Our speed over the bottom slowed to less than a knot. We started the other engine and by the time it was warmed up and at the same speed as the other, we were still going less than a knot. Maryanne unrolled the jib and got it pulling and we were still going less than a knot. Then we slowed down. Then we stopped. Then we started going backwards with the knot meter saying 7.5.

We nudged over to one side as far as we dared and found we could go forward at about 0.3 knots. If we could only speed up to .324 knots, we could go a boat length a minute. It got a little choppy on that side, which killed our speed, so we went across the center to the other side, losing about 50m in the process before we started going forward again. In all, it took us about an hour to get the ¼ mile through the narrow part of the pass.

We approached the anchorage near the town and found something even better. The Military had left behind a little protected harbor where we could tie up for free. It was just a mile or so out of town.There were three other boats tied up on the seaward side, so we pulled up next to the house on the land side. Aleen rode over from her boat Pizza to catch our lines. We then had a series of welcoming committees from the other boats and locals passing by, each giving us a full briefing on what Hao had to offer and where to find it.

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