The trawler yacht is a descendant of its working cousins, the tugboat and the trawler fishing boat. Maybe it is tradition, maybe preference, but these yachts are often equipped with Bitts and / or Bollards just like their relatives. Just like other boats they still have cleats, but Bitts and Bollards are there to do the big jobs.
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.
Friction is necessary to keep lines attached to Bitts, Bollards, Cleats, Lines, or other things. Friction increases as the "normal force" increases. The normal force is the perpendicular force between two objects. When the load on a line increases, say by the boat drifting away from the dock with the line tension increasing as a result, the normal force between the line and the Bollard increases and therefore the friction increases. The connection will hold if the total friction between the wraps of the line and the Bollard is greater than the force on the line to the boat, otherwise it will slip.
Line connections to Bitts and Bollards can be made to quickly release or made for a more permanent connection. The problem with the quick release method is that a boat tugging on a line can cause it to become undone. Alternatively, when a line is positively tied off it may be hard to undo when required or when in a hurry. If a pre-tied loop is to be used the difficulty is that its size has to be predetermined which may not be possible when the intended bollard is on a dock yet to be reached. Also, a loop may not be a positively secure way of attaching to a Bollard. However, a loop may be used as a Lark's Head on a double cruciform Bollard. This would be a very secure attachment in my opinion and if it does not have a load on it, it can be released quickly. If loaded, however, it cannot be easily released. Another way to more securely attach a loop to a single post Bollard is to first place the loop over the Bollard and then put a half twist in the loop behind the Bollard to form another loop and then bring the resulting second loop back over the Bollard toward the front. A larger loop will be required for this, but the result is more secure than just dropping a loop over the Bollard.
The bowline has been called the king of knots. Nothing can jam it. It will never slip if properly made. It can be tied in the hand forming a loop that may be dropped over a cleat, Bitt, or piling or formed around a mooring ring.
A Clove or ratline hitch is a convenient knot for making a line fast to a spar, the standing part of another line, a piling, or a Bollard. It is used to temporarily fasten a line, but it must be watched as it might undo if slack. When under a strain, however, it will not slip, but when under a hard strain, it will set up tight and may be difficult to break loose.
The correct method of securing a line to a double Bitt is to make one turn on the first post of the Bitt and then make several wraps of the line in a figure eight pattern over both posts of the Bitt. This method may be undone quickly if necessary. Further security may be had by belaying the bitter end coming off the Bitt on a nearby cleat. On a single post Bollard the usual way is to use an appropriate sized loop of line over the Bollard or as described earlier or tie several hitches to the Bollard. A Bollard with cross pieces will help keep a loop from slipping off; even so secure ways of belaying are preferred to ensure that the line will not accidentally come off.
A method known as the Lighterman's Back Mooring Hitch may be used on a single post Bollard, on a piling, or for heavy towing. This method is used on tugboats and is called the Tugboat hitch and sometimes the Backhanded Mooring Hitch. It is a well known and trusted attachment and, like the figure eight described earlier, can be undone even if there is a massive pull on it. Once learned It works well when you wish to moor to a Bollard (maybe whilst waiting for a lock or taking on water etc.) and can be tied or untied in moments.
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