The trawler yacht stems from its working cousins, the trawler fishing boat and the tugboat. Whether it is tradition or preference, often these yachts are equipped with Bitts and / or Bollards just like their relatives. Of course they have cleats as well, but the Bitts and Bollards are there to do the big jobs. light bollards for driveways
Now if you have a trawler yacht, you might want to know the correct way to belay a line to one of these babies. Well, first let’s look at them because there are many styles. If your boat doesn’t have all of them (and I have never seen one that does) then you should pay attention anyway because chances are the docks that you pull up to will sooner or later present the other styles, especially if you travel around the world as trawler folks like to do.
Bitts and Bollards are heavily built devices for belaying lines. Bitts may be classified as single, double, H-Bitt, Cruciform Bitt and others. Bollards may have a single post, double posts (either vertical or angled outward from center), Cruciform, staghorn, and many other styles. Sometimes Bitts are called Bollards and vice versa.
Lines rely on friction to keep them attached to Bitts, Bollards, Cleats, Lines, or other things. Friction increases with what is called normal force. Normal force is the perpendicular force between two objects. So, for example, when the load on a line increases (the boat drifts away from the dock and the line tension increases) the normal force between the line and the Bollard increases and the friction increases. If the total friction of the connection to the Bollard is greater than the force on the line to the boat, the connection holds.
Lines can be secured to Bitts and Bollards in such a way that they can be quickly released or made with a more permanent arrangement. The first such method has the problem that a boat tugging on a line can cause it to become undone or alternatively, if a line is positively tied off it can be hard to undo when required. The obvious difficulty with using a pre-tied loop of line is that its size has to be predetermined which may not be possible when the intended object for the bitter end is not in sight. A loop may not be a
positively secure way of attaching to a Bollard. It may be used as a Lark’s Head however with a double cruciform Bollard which would be a very secure attachment in my opinion and it can be released quickly if it does not have a load on it. If loaded it cannot be easily undone. Another way to more securely attach a loop to a single post Bollard is to place the loop over the Bollard and form another loop behind the Bollard by making a half twist in the loop and then bringing the resulting second loop back over the Bollard toward the front. A larger loop is required for this, but the result is more secure than just dropping a loop over the Bollard.