How to sail home

Datum: 13.03.2024
Position: Western / Northern coast of Cuba
Nautische Position: 23°17’N 083°40W
Etmal: 182nm
Total: 7920nm
Schiff: Pelican of London

Homewardbound

Today we made our way around the west coast of Cuba, so from now on the compass will remain between 0 and 90 degrees, which for us means home. And indeed, it’s not hard to grasp a going-home-vibe amongst the inhabitants of the Pelican.

This does not mean that we are waiting to come home, we are still enjoying our time at sea, among the wind and the waves of the last bits of the Caribbean Sea. But many people are starting to write lists on what they are looking forward to, especially including food.

How we are getting home: The currents

At the moment, we are still heading pretty much north, because (similar to the first Atlantic crossing) we will use the help of mother earth (the gulf stream) to carry us back to Europe.

The impact of currents can be overseen quite easily: It’s not as obvious as the Passat winds, but when you see the course varying from our heading, when you notice an additional half a knot or if you suddenly measure a much higher sea water temperature, then you know that you made your way into one of the most powerful sources of movement found on earth.

The winds in our sails

Most people would probably think square sails to be the most important sails on a tall ship. And that’s not completely wrong: They are huge sails, most often the largest sails on a tall ship and especially for aft winds (like we had them on the first Atlantic crossing) really effective.

This is because they work mostly on impulse forces; forces that push from behind the sail, giving us a forward impulse.

This is all fine if you have wind from astern, but if you want to sail closer to the wind you’ll quickly notice the disadvantages of a square sail:

1. Sideways push: When you have wind from the sides, it pushes you sideways of course, even if your heading stays the same

2. Shifted point of effort: The point of effort is basically the turning point of the ship relative to the wind. You can think of it to be the point where (for your wind direction of interest) you could hang up the Pelican on a yarn so that it would stay in a state of equilibrium. The problem is now that if that point is because of the large sidewards squaresails, behind the actual middle point of the ship, it forces the ship to turn its nose into the wind. And with your nose in the wind, you can’t sail.

3. Limited range of courses: You simply can’t sail any closer to the wind than about 70 degrees.

4. Hardly any lifting force: Besides the impulse force there is a force even stronger which is called lifting force. It’s a hydrostatic force which works similar to what happens on airplane wings. Because of the shape of the sails the air travels faster on one side than on the other, creating a pressure difference that pushes the ship forward.

And that’s why fore and aft sails are so important. They have strong lifting forces, are needed to control the point of effort and you can sail as close as 30-40 degrees to the wind.

Furthermore they are very helpful in stabilising a ship, also under engine.

So to get us back through different winds, back to the coast of Amsterdam, without having to have steady aft winds we need our pretty for and aft sails.

The steering

Even though it would be technically possible to sail back, without ever touching the helm, just by moving the sails, practically we need our helm. Our steering works on hydraulics: The turning of the wheel pumps water (according to our engineer) through a hydraulic system building up pressure that turns our rudder.

The turning of the rudder changes its water stream direction, which then steers the ship. The efficiency relies here on the speed of the water stream and the angle of the rudder. This is why for lower velocities you need more helm.

And it is also part of the reason for a time delay between steering and the ships movement especially when steering backwards.

What we learned

Those are only some of the ingredients that we have to learn about, that we have to understand and deal with to become able to sail. There was much more for us to learn on our way till Cuba and there will be even more from here on over Bermuda and the Azores back to where we started almost five months ago.

Schülerin im Klüvernetz
Nach oben scrollen
×