Navigation charts

Luckily for us aboard The Aegre, a number of our navigation charts survived our capsize and swamping mid-Pacific.

We kept most of our charts rolled up and secured under the deck between the beams, secured by a cat’s cradle of shock cord. But of course, they were totally immersed in the capsize and then remained soaking wet for another ten days until the weather started to improve and we could try to dry them out. Many disintegrated. But thankfully, some survived. In addition, we had an Atlas of World Pilot Charts stowed up forward, and these survived rather better. We used one of them, a Pilot chart of the South Pacific, to plan and track our subsequent passage to Samoa.

Almost as surprising, I still have some of them fifty years later. Rolled up, dusty, rust-stained and tattered around the edges, they’ve been tucked away in a box and survived multiple house moves, periodic de-clutters, and attempts by others close to me to chuck them out. But here are a few of them.

Hiva Oa – Marquesas Islands – South Pacific

This is the chart we used to plot our position as we approached Hiva Oa in the Marquesas Islands. We were coming from the east (the right-hand side of the chart), having sailed 4,200 miles non-stop from Panama. We wanted to reach the safest anchorage on Hiva Oa in daylight. To do this, we planned to close with the tiny island’s unlit eastern end before dawn. Tricky after sailing so far. Was our astro-navigation correct? How we did it is described in Chapter 15, 4000 miles in 21 ft.

Here’s a closer view of the approach to the best anchorage on the island. You can just see the pencil line of the bearing I took on the intercept of Tahuata island to the south and the southern point of Traitor’s Bay, giving an accurate position line.

Later we sailed through the western end of the Tuomotu Islands and very nearly came to grief on Arutua atoll. See Chapter 16, The Marquesas to Tahiti.

After the capsize, most of our charts were unusable, but an atlas of Pilot Charts survived surprisingly well, and we used one of them, of the South Pacific, to plan and track our subsequent passage to Samoa. Pilot Charts are incredibly useful to the navigator planning a passage (see here for a explanation of them). But they are a relatively small scale and not intended for live navigation, but they were the best we had. Below is the same one as we used, but for the June-July-August quarter.

Here is an enlargement of the section we used to plan and track our course to Samoa after the capsize: From the Society Island (Tahiti) to the Cook Islands (Rarotonga), the Tonga Islands and the Samoa Islands. To better understand all the symbols on the chart, follow the link above.

Below: Here’s another interesting chart, ‘Sailing Ship Routes’. Under sail, the shortest course between two points is often not the fastest. This chart, drawing on reported wind data over decades, shows the fastest, in general terms. (Modern Pilot Charts, such as that above, show much more detail and variation by seasonal quarter). I had a copy of this chart onboard, but it didn’t survive. So the image below is of a replacement that John Ridgway and I drew on to plan the Albatross Voyage circumnavigation in 2003-4.

I suppose that with GPS, electronic charts, and their integration with radar, big paper charts are all a bit redundant now. But they shouldn’t be. I love them.

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