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A stolen moment, capturing the calm afternoon light before rushing off to tidy up the mess we made after trimming and setting sails. (Photo: Vår Dundas)

Drifting westward on the currents while zigzagging our way eastward

The currents are pushing us westward while we try to move eastward. Vår Dundas writes about sailing when both the current and the wind work against you, and a bit on the excitement of sail furling. 
 

Body

The compass needle indicating our ship’s direction is swaying lazily from side to side as our ship bobs back and forth in the calm afternoon breeze. It smoothly responds to my adjustments at the helm, and nicely indicates the northeastward direction I’ve been instructed to maintain.

However, I know that our destination is straight eastward. And when I glance down at the map that shows the path we’ve traveled, I realize that we drifted more westward than I thought. 

I’m learning quickly that there are a million aspects to consider if you want to keep this ship on a steady course. Wind and ocean surface currents are two of them.

Sailing into headwind

Here, in the Equatorial Pacific, the steady Trade Winds dominate, and as Kjersti described in her piece “Battling the Trades”, they blow westward. This wind forces the surface current to also go westward, and since oceanography is my field, I’ve been curious to know what role the currents have for our navigation. 

Form Kjersti’s “Battling the Trades” we also know that it is not possible to sail straight into headwind: To travel against the wind we must follow a zigzag pattern.

Looking at our track from Suva towards Tonga, it appears as if we had no sense of direction.
Looking at our track from Suva towards Tonga, it appears as if we had no sense of direction.

In our case, this means that since we want to travel eastward towards Tonga, we have to sail northeast, then southeast, then northeast and southeast again, slowly making our way eastward.

To make sure we catch the wind properly we’re left with lots of sail maneuvering: up and down with the sails, trimming the sails back and forth, and tidying up the ropes on deck after all adjustments are done. It is hard work, but I find that I really enjoy these tasks – climbing up the rig to strap the sails nicely in place on top of the yards (furling the sails) is turning into one of my favorite activities on board.

Drifting with the currents

Compared to the wind, the currents here in the Equatorial Pacific are weak. In addition, the sails of a tall ship have a much larger area than the ship’s keel, and while we can change the angle of the sails to catch the wind, we cannot change the angle of the keel to catch the current.

Consequently, the wind is the most crucial factor when navigating a sail ship. Still, the currents can’t be completely disregarded, which consoles the oceanographer in me, the ocean always plays a role, doesn’t it? But the currents are pushing us off course – and my consolation is gone as the currents are working against us. 

Earlier today we were sailing northeastward with the wind coming in from the east. But due to the currents and the waves also coming in from the east, we were pushed roughly an additional 10 degrees off the eastward course we’re ultimately aiming for. So, while the currents are not our most important consideration, they do affect our sailing, particularly when they hit us straight in the side.

The stronger the current is, and the closer it is to hitting the ship straight in the side, the more efficiently the current pushes us off course. So right now, the currents are pushing us back where we came from, making our eastward travel a very slow progress. 

All the maneuvering has, however, helped us become useful on deck surprisingly fast. In a few days we will turn westward again, sailing back to Fiji, with both the wind and the currents on our back.

Then there will be no more zigzagging and drifting off in the wrong direction due to the currents, but hopefully the crew will still need our help with some sail furling, sail setting, and general rope pulling in our last week of sailing.