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Gladstone North Channel

Gladstone North Channel

While Gladstone is a great place to stop for a couple of days, it is quite a distance from open water. Except for the Main Ship Channel, there is also a lot of shoal water, so one has to pick your access route carefully, with due consideration of the tide.

While we could have saved hours going directly to Keppel Bay via the “Narrows” the tides are just not high enough today. We would need a 3.6m tide to get through the shallowest part at the “Cattle Crossing”, where it dries to 1.3m at LWS. As it is neap tide at the moment we would have a maximum of a 3.3m tide, so that route was out of the question. That left the “North Channel”. I asked the advice of the owner of the local bait and tackle shop – a keen angler – and determined that the North Channel was doable, as long as we had a tide greater than our draft of 2 metres. This meant we could leave any time after 10AM, with high tide (3.3 metres) at 14:24.

We followed the route recommended by my new friend, and it was just as advertised. On a 3 metre tide height we never had less than a metre under the keel. Note though that there are several shoal areas along the route, so one has to make sure you have enough water right from the start until out in the open water. Our track and route through the North Channel are shown in the screenshot.

The Romantic Navigator

The romantic in me insists that sailing belongs to a time when real men with long grey beards squinted through brass sextants to fix their vessels’ positions with pin-point accuracy, predicting landfall to the nearest hour… That hasn’t stopped me from kitting Sunny Spells out with the latest GPS chartplotter; in fact, at last count I carry four GPS receivers on board if I include my Nokia Navigator mobile phone. Hopefully the handheld, floating Garmin GPS and spare batteries travelling in a tin in the grab bag will survive a lightning strike…

Before our first passage I purchased an updated set of paper charts of the Australian East Coast, just to be sure, and a Davis Mk III sextant came my way at Birthday time, so now I had the tools, if not the skills.

So, how to acquire the skills?

The sextant came with pretty good instructions: it comprises about 10 pages, notebook size, with enough information and the basic tables to enable you to calculate a fix from a noon sighting of the sun. This was a revelation to me, as one of the things that always made me shy away from doing the sextant thing (sounds suggestive, eh?) was the perceived need to carry volumes of tables and almanacs to do the calculations, and update these every year.

While on passage between North Keppel Island and the Percy Isles in July 2008 we floated downwind under spinnaker for hours on a calm sea: ideal conditions for learning the intricacies of the sextant.

Lesson 1: adjusting the sextant was a doddle, maybe because my instrument is so simple. It was quite a thrill though, finally holding the sextant in my hand and getting a feel for how it works.

Our next opportunity for continuing the education was two days later while continuing north from Middle Percy Island to Scawfell Island. In about four paragraphs of instructions and one small table I had enough information to do a noon sighting of the sun and plot our position to within 10 nautical miles! I was well pleased knowing I can now, in an emergency fix our position once a day and know that, with very limited data and an accurate timepiece, I can be within about 10 miles.

With my new found knowledge I could also show the crew how to take the sights and we all took turns to take sights every three minutes from about 11AM onwards – great practice.

Vicky taking a noon shot of the sun while George takes the time and logs the readings