Picture the scene aboard two yachts, sailing the same course on a summer’s day. They are in exactly the same place, each in a parallel universe to the other: A healthy breeze streams across the deck, ruffling your shirt. The yacht is nicely heeled, powering forwards on a comfortable, close reach. The sky is a deep blue, with cirrus clouds slow-waltzing serenely above. The sea has some green to it, with a moderate swell running, and occasional wisps of spray sprinkle the foredeck as the hull rises and falls to a steady rhythm. Off to starboard a sail has appeared on the horizon – presumably running downwind, though it’s hard to tell. To port, a tanker is passing. A glance back at the sails. Perhaps the headsail is sheeted slightly too hard? Slacken that off just a fraction. The miles wash by.

When sailing, balance the rudder or you will increase drag, putting strain on the rig, rudder and stock; plus you will need more canvas up to achieve the same boat speed. Credit: Richard Langdon/Ocean Images

Teleporting to our parallel universe we note that the companionway readout for the windspeed generally hovers around 16 knots, but if we look long enough, we do see occasional gusts rising to 21. Does that mean we should reef? The angle of heel on the inclinometer hovers around 18°. The autopilot readout shows the rudder correction sits around 8°. We’ve one eye on the AIS as SV Summer’s Breeze gradually bears down on us. Their course is 193°, still four miles away. Thankfully that tanker has passed. It was hard to know if they had seen us on AIS or radar for a minute there, and they hadn’t answered the radio. Speed over ground (SOG) is 5.6 knots.

You get the idea. In our modern, data-rich world it seems logical that sailing can benefit from this. The information can feed systems, making life at sea easier and safer – or so the argument goes. Instrumentation and data promise more time to enjoy everything a life on the water can offer, as well as allowing us better insight into how the boat is behaving. Perhaps all these numbers might even make us better sailors. I’m not sure it’s quite that simple.

Take autopilots

Electronic autopilots first appeared for yachts sometime in the 1970s. Nowadays, they are near ubiquitous. They are an incredible tool, an extra crew member and increasingly powerful and reliable. They also help skippers get away with poor sail trim at times; completely unbalanced, the rudder is permanently angled well away from the centreline of the yacht, increasing rudder drag, and adding strain to the rudder and stock. That extra drag also requires slightly more sail up to achieve the same boat speed, and so strain on the rig may also be marginally higher.

More seriously, the ability to correct yawing is reduced with the rudder already well angled, which could even become critical in a seaway. A tendency to pay less attention to sail balance may be exacerbated by the rise in form stability of many modern yachts and a simultaneous decline in directional stability.

Compared to the yachts of yesteryear, many modern designs with wide transoms and narrow fin keels are often very good at staying upright but not so good at tracking a straight line. The result? With directional stability now reduced, I believe some skippers slide into eventual apathy to sail balance; they stick the autopilot on and forget about it. No need to worry about the extra drag from the rudder as higher form stability means she stays upright longer, so you can keep sail on her for longer.

The principles for balancing a boat remain the same regardless of keel shape; the key is learn the nuances of your boat. Credit: Richard Thomson

Not untrue, perhaps, but it is still poor seamanship and less kind to the boat. In an unfortunate series of events, it could even become unkind to the crew for the reasons hinted at above.

In contrast, traditional yachts with longer keels generally track extremely well. Our 1983 38ft Trident Marine Voyager Namika has a long-chord fin keel with a cutaway forefoot, and we sailed her for two seasons without self-steering. With some experimenting with sail trim, we discovered she’d sail herself for hours at a time, anywhere from close-hauled to a broad reach depending on the sea state.

Generally, we had to lock the rudder ever so slightly to leeward (perhaps a degree or two at most). Having since added a staysail, the helm can now be completely centred above a beam reach. These experimentations with sail plan, trim and balancing the yacht were hugely beneficial and undoubtedly made us better sailors.

They were also fun: it forced us to pay more attention to the behaviour of the boat, to the effect and trim of each sail, and to the wind and waves. I remember being like a child on Christmas morning when we first locked the helm and were counting the minutes (and later the hours) that Namika held her course alone.

Though we have since added an autopilot, I still take pride in centring the rudder using the sails, and spend time actively tweaking as the hours go by. As the wind increases or decreases, the angle of heel changes and this affects Namika’s balance, which sometimes calls for a change to sail plan or trim without a change in wind direction or course.

All in the balance

There are many single-handed sailors who have covered incredible distances when their self-steering gear broke. Joshua Slocum famously sailed around the world with no self-steering at all, relying purely on sail balance and lashing the helm from day one. Sir Robin Knox-Johnston used a wind vane and carried spares in the 1968 Golden Globe Race, but after his last spare broke near Australia, he sailed the remaining halfway round the world and home by balancing the sails, inspired at least in part by Slocum.

However, both Slocum’s Spray and Knox-Johnston’s Suhaili had long keels. Does this mean there’s no hope for the narrow fin keels so common on modern yachts? I’d argue the contrary. They may be harder to balance and keep balanced, but fundamentally the principles remain the same, and every keelboat and multihull I’ve sailed could be largely balanced on at least some points of sail.

Spend time centring the rudder using just sails alone. Credit: Richard Thomson

If you have not already, next time you are out on the water with a bit of time and sea room try to get the rudder centred, or as near as possible to it. At its most basic, if there is weather helm (ie the bow wants to turn into the wind), the rudder would have to be pointed somewhere to leeward to maintain a straight course. To balance this you’ll need more pressure forward of the pivot point; in other words more pressure from the headsail (or less from the mainsail). If there is lee helm (ie the bow wants to turn downwind), the opposite is true.

Initially I’d suggest first experimenting with the sheeting angle to change sail shape or, depending on wind strength, by selectively reefing fore or aft of the pivot point. Finer control can be achieved by moving the cars for the headsail (if you have them), adjusting the tightness of the vang for the mainsail, and moving the mainsail traveller to adjust sail twist. There are other adjustments such as halyard tension which you could move onto later, and of course if you have a cutter or a ketch there are even more options to play with.

Experiment with sail trim and even the sail plan, and you will eventually find the correct sail balance for your boat. Credit: Richard Thomson

There’s been a lot written on sail trim and there are many resources which will better explain the theory than I can, but yachts are all different and I’d suggest the best thing you can do is get out there and do some experimenting on YOUR yacht. Switch the autopilot off, try adjusting sail trim, and you might be surprised what you can achieve.

I’d challenge anyone to spend a few hours experimenting, make some progress and would be very surprised if it fails to raise a smile. When you manage to get the boat to sail straight by locking the helm (without a helmsperson, autopilot or wind vane), a logical next step could be to experiment with adjusting course using just the sails. You do this using the same logic: by altering sail trim so the sails are temporarily unbalanced. You can even gybe this way. Try it.

Reef by feel

I have similar feelings about other instruments. I know plenty of skippers (many of them good sailors) who reef according to wind speed shown on their anemometer. Others do it by the angle of heel on their inclinometer. We don’t have an anemometer, inclinometer, or an electronic wind direction indicator for that matter. There’s just a wind vane at the top of the mast, and even that you could do without if you were feeling spartan.

Instead, we reef by feel: the boat starts to seem pressed, perhaps uncomfortably heeled, the sheets might groan on the winch as the ropes stretch that little bit more. A yacht can be quite chatty if you’re listening to her. Linking back to our discussion of autopilots, the underwater profile changes as heel increases, and so the rudder has to move away from the centreline to hold the course. A helmsperson should notice this.

An anemometer will only tell you wind speed at your yacht’s precise position; squalls generally can be spotted well before they hit, giving you time to adjust your sails accordingly. Credit: Theo Stocker/Future PLC

If the sails had been balanced and the wheel locked or lashed you’d notice a change of course. If the autopilot is on and you aren’t paying attention, you might not notice at all. Rather than looking at instruments, if you have half an eye on the trim, heel, rudder, and course you can make the call to reef (or set more sail) based on how the boat behaves. In time, you can feel the yacht’s behaviour with your eyes closed.

The trouble with reefing by numbers is that it doesn’t take account of other variables such as sea state, or gusts. If the sea is flat, you might feel comfortable carrying sail slightly longer than you would if the seas are large – 25 knots with a low-lying coastline to windward and a flat sea is completely different to 25 knots with a 2-3m swell running.

If you listen carefully, a yacht will tell you when it is time to reef, such as when sheets start groaning on the winch or heel becomes uncomfortable. Credit: Richard Thomson

Though sometimes overlooked, the Beaufort Scale is an estimate of experienced conditions, not wind speed. In other words, it includes wind speed AND sea state. And if conditions are gusty, should you reef according to the maximum windspeed you see, or the average? Depending on the situation, it might be prudent to actively helm or to occasionally spill wind instead.

In a seaway with gusts, you might want to keep slightly more sail up to prevent the yacht from rolling around in the lulls. Or you might not: my point is that I don’t think the answer is in the instrumentation.

Wind speed indicators or inclinometers might be interesting, but I personally don’t think they should change how you sail. An anemometer can also only tell ywind speedndspeed at a precise moment in a precise position: the yacht’s position. An approaching squall can generally be seen in daytime if you’re looking at it. I don’t know of any instrument that can tell you what the wind speed is half a mile to windward. By the time the squall hits and it shows on the instruments, you may have already reefed or taken some other action.

On Namika, we shorten sail as soon as anyone thinks about reefing, based upon the feel of the boat and the state of the sea and sky around us. At night, we sail slightly under-canvassed. In contrast, we have seen countless yachts hit by squalls and their crews scramble to reef with the wind suddenly howling around them. Perhaps if they’d been less surrounded by or focused on instruments, they might have seen it coming?

Chartplotters are not infallible, so always make sure you pay attention to your environment. Credit: Theo Stocker/Future PLC

One final thought on GPS, AIS and positioning this time. Now, I’m not going to bash GPS. It’s an incredible facility to have on board whether using chartplotters or tablets. That said, to my mind (and with reference to the theme of this article) there is one oft-overlooked advantage to the paper chart: you KNOW you are rarely ever 100% sure exactly where you are, and you hopefully exercise caution because of it, trust your feel in relation to your fixes, and act accordingly.

In contrast, GPS provides a position that will most likely be accurate to a couple of metres. However, the chart it’s plotted on could be based on surveys that are 100 years old (sometimes more) and potentially inaccurate. I’ve personally experienced these discrepancies, even in the well-furrowed sea lanes of Europe.

Furthermore, with the rise in geopolitical tensions we must perhaps become ever more aware that GPS is not neutral: it is operated by the US Government which retains the power to disable or degrade the positioning at will. Likewise, it may in specific locations be subject to jamming by powers hostile to the US. The same applies to the various alternative global satellite positioning systems, whether operated by the EU, Russia, or China.

This doesn’t mean I believe GPS or its alternatives should be ignored, but they still require comparison to the world we experience around us as we sail, with positions compared to observed waypoints, landmarks or other fixes taken.

Awareness of surroundings

We could have the same discussion about the rise of AIS and radar. Great as these features are, not all boats have them, systems can malfunction, and they still require someone to check the screen or listen for an alarm.

I remember reading the account of a single-hander reflecting on the time it would take for a reasonably fast tanker or freighter to appear over the horizon and potentially run down a yacht. A sobering 20 minutes is all that may be needed. Robin Knox-Johnston was famously horrified to conclude there was clearly not always a lookout kept aboard merchant shipping, and so there remains an onus on yacht crews to keep a lookout.

AIS Is a great asset, but not all boats have them so make sure you still maintain a good lookout. Credit: Nick and Wendy Taylor

That’s really the overarching point I want to make. By looking up from our instruments we better attune our senses to the world through which we sail. Maybe we could even turn some instruments off from time to time. If you’re thinking of splashing cash on fancy new tech perhaps pause and ask yourself how much value it will really add.

I’m not anti-instrumentation, but do fear the explosion of data may be dulling the senses of many a skipper. Doing without would certainly improve our feel for the boat and the situation around us. In an ever-more digital world, surely that’s as good a reason as any to cast off the shore lines? I for one did not go to sea simply to sail by numbers.

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