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• Radio Reception in the Louisiades
• Chart Accuracy vs. Eyeball Navigation
• CMAP - the "Free" Version
• Cruising Guides
  • SV Clementine's Guide to the Louisiades
  • Dim Dims and Dolphins
• Waypoints & Tracks
  • Tracks of SY Aequus
  • Yacht Blogs Featuring Louisiades

Radio Reception in the Louisiades

We did not find much in the way of local broadcast radio in the islands. If you like to know what is going on in the world and back home in Australia, it is useful to know the short wave frequency schedule of ABC Radio Australia. HF Radio is not just for news junkies it is also very useful since the ABC does broadcast tsunami warnings if there have been quakes in the pacific.

• Radio Australia
• BBC World Service

Chart Accuracy vs. Eyeball Navigation

The Australian Hydrographic Office has recently issued "new" metric charts for the Louisiades region, however pay close attention to the Zone of Confidence parameters! Be warned - even these new charts are only accurate to about 500m, which is not really good enough for confident and safe navigation amongst coral bommies and fringing reefs!

We navigated the islands using a combination of electronic charts (C-Map Max-NT version 14 displayed on a laptop using Software On Board), the latest paper charts as of September 2009, and cross referenced between GPS, RADAR, depth sounder, and hand bearing compass whenever we approached a new anchorage for the first time. Generally speaking, we found the relative location of islands shown on paper charts to be consistent with ranges observed on RADAR when negotiating charted passages through the reef. Furthermore, the Max-NT charts appeared consistent with the paper charts.

On the other hand, we encountered several submerged obstacles (expansive bommies) 100m from their charted position - according to our GPS. We did not have the opportunity to determine whether this inconsitency was due to inaccurate chart survey or GPS error, however it reinforced the importance of only navigating with good light in unfamiliar territory!

Nevertheless, we always approached new anchorages cautiously, and with good light and several lookouts. This is particularly crucial in tight anchorages, and any time you want to anchor particularly close to a fringing reef, as the depth may jump from 12m to 2m or less!

CMAP - the "Free" Version

Many yachties seem to have an old copy of CMAP running on their navigation PC. I've used it in the past, and it seems reasonably accurate for well-surveyed, high traffic locations such as the east coast of Australia. However, this software is based on pretty old chart data, and cannot be relied on with any confidence for navigating within the Louisiades. There is a huge difference between the $300 "C-Map" charts and the public domain charts, and Jeppesen Marine release updated charts every few months which incorporate chart corrections published by the relevant hydrographic authorities.

Cruising Guides

SV Clementine's Guide to the Louisiades

This book served as our main reference to anchorages throughout our time in the islands. Although the general information and mud maps of the anchorages are very useful, some of the GPS waypoints provided are dangerously incorrect. At least one appears to be a typographic error, and several others left me wondering if the author was using a GPS datum other than WGS-84. Given our own observations and the lack of any mention of datum, we recommend treating SV Clementine's waypoints with cautious suspicion. Also note that some of the information about villages or islands being uninhabited is either out of date or incorrect. Boat Books and other Australian chart agents tend to stock the SV Clementine guide.

Dim Dims and Dolphins

We were unable to get a copy of this book in time, however many other rally participants used it. Perhaps someone would care to review it here?

Waypoints & Tracks

Tracks of SY Aequus

The following illustrations are screenshots taken from Software on Board using CMAP MAX NT charts (version 14) at maximum zoom. Aequus is a Jarkan 10.5 and draws 1.8m with full cruising stores. GPS Datum is WGS 84. We will publish the tracks in text format at a later date. Please remember that GPS is only accurate to about +/- 20m about 95% of the time. The other 5% of the time it may be better, or much much worse! These screenshots are provided to give an approximate indication of navigable routes, however you must take all due precautions (cross reference with depth sounder, RADAR, paper charts, handbearings, and good visual lookout) if you choose to follow them.

Location	Click For Full Size
Cairns to Louisiades
Track - Arrival at Duchateau from Coral Sea
Track in/out of Kamatal
Track from Bagaman to Panaumala
Track from Gigila to Wanim
Track to Panapompom and Nivani
Track from Panaumalato Gigila
Track from Utian to Bagaman
Track from Wanim to Nimoa
Track into Panasia Lagoon

Yacht Blogs Featuring Louisiades

• Yacht Maranatha - An Australian couple who sail to the Louisiades every year to carry out missionary work