The Offshore Voyaging Reference Site

It Ain’t Necessarily So

In these days of hyper-accurate GPS navigation and deck mounted plotters, it can sometimes seem like navigation has been reduced to no more than a video game.

And it sometimes seems that more and more people are implicitly trusting what they see on a screen, having never known the nervous twitch that accompanied entering a new bolt hole in the days before the magic of satellite navigation. But when sailing in remote areas where so much remains uncharted or uncertain, sometimes the latest kit doesn’t always help.

In the early 1990s, when I first started skippering boats on the west coast of Scotland, GPS was still in its infancy. But for those of us weaned on nothing more sophisticated than compass and chart it was a revelation, except when close to shore when we reverted to the old methods. And at that time, there were still a few of the old fishermen’s painted transits to be found in some of the tighter entrances to sea lochs, which were wonderfully effective. So eyeball navigation still predominated, coupled with religious reading of every available pilot book to get the maximum amount of information into your head before attempting a tricky entrance for the first time. And because we simply couldn’t be certain of the position of some charted rocks (let alone the uncharted ones) in the way we believe we are today, everything was taken really slowly, with tide rising and good visibility in our favour. We didn’t push our luck, but understandably there were still occasional ‘surprises’.

This was partly due to the lack of accurate information in these remote places, and this was at its most obvious each year when the pilot book corrections arrived. In our home waters of the English Channel these would usually amount to no more than half a page or so for a really substantial stretch of coastline, and mainly consisted of changed light characteristics and the occasional new wreck. The Scottish ones were an order of magnitude different—pages for each pilot, and more often than not with laconic entries such as “obstruction found in position….”. Well, yes—it was only too easy to imagine how the obstruction had been ‘found’.

And some of the charted and pilot information was plain wrong. Entering a tiny harbour with an entrance that would have been best described as ‘nadgery’ (tight and tortuous) in west country vernacular, timed to be there with over a metre under our keel for us to cross the shingle bar, we were surprised to ‘discover’ that there was no metre and the bar consisted of boulders. Once inside we tried hard to find the promised minimum 2.5m depth anywhere, and couldn’t. Yet the chart and the pilots were unanimous that their information was correct. And so it’s easy to see how all of the cutting edge wonders of screens and software won’t help if the basic information isn’t right in the first place.

And it’s easy to become complacent with all of our space age kit, and that can lead to corners being cut, and chances taken. I was reminded of this last summer entering one of the loveliest inlets at Loch Moidart on the rugged Lochaber shore. I hadn’t been in there for several years, and the entrance looked different—just a trick of age and memory in fact, but enough to warrant extra care. With careful pilotage and slow speed we were soon safely in and well on our way up the loch. Glancing at the plotter I noticed that our track line had disappeared for a large chunk of the distance travelled, and our position had shifted by a substantial distance, probably due to insufficient chart data. No big deal, but potentially a nuisance on the way back out if conditions were less than perfect, or for a newcomer unaccustomed to old fashioned plotting and pilotage.

I’d be the first to agree that modern navigation equipment is a real asset, and I’d much rather have it onboard than not. And it’s also true that as a result of having it onboard I’m probably more bold in my choice of entrance or anchorage than I would have been 20 years ago, and that has definitely enhanced my enjoyment of cruising on occasion. But at the same time, it has to be accepted that these modern devices are not infallible, and can only function effectively when they have accurate and adequate information. It was certainly a timely reminder for me that when sailing in remote places we shouldn’t rely entirely on what appears on a screen, but also use traditional navigation methods, imbued as they are with a taste of humility and a sprinkling of uncertainty—still vital elements to keep us out of trouble even in today’s byte driven world.