The bowline on a bight is a
knot
A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ' ...
which makes a pair of fixed-size loops in the middle of a rope. Its advantage is that it is reasonably easy to untie after being exposed to load. This knot can replace the
figure-eight loop
Figure-eight loop (also figure-eight on a bight, figure-eight follow-through, figure-eight retrace, Flemish loop, or Flemish eight) is a type of knot created by a loop on the bight. It is used in climbing and caving.
The double figure eight i ...
knot when tying into a climbing harness. It is one of the two tie-in knots that are being taught by the
German Alpine Club (DAV), generally being considered secure.
Dangers
2011 testing shows that the knot might slip when only one loop is loaded. Cavers and canyoneers ought to fasten their cow-tail carabiner through both loops.
[ Video with genuine ''et voilà!'' ending ] European cavers widely advocate the use of
a figure eight twisted version of the bowline on a bight.
Applications
This knot can be used to provide a toe hold in the middle of a rope; to make an emergency
bosun's chair; and to create an upper rope "block" to make a crude purchase by threading the rope round an anchor point and then back up through the loop. It is sometimes used in
sport climbing
Sport climbing (or Bolted climbing) is a form of rock climbing that relies on permanent anchors (or bolts), permanently fixed into the rock for climber protection, in which a rope that is attached to the climber is clipped into the anchors to ...
to tie into two anchor bolts independently. This knot is convenient when a dependable loop is required but neither end of the line is available. It's also commonly used as a seat while being hoisted as there are two secure loops as opposed to the traditional one loop bowline. In theory, this knot would make hoisting many people with one line possible. This knot is very popular in
caving
Caving – also known as spelunking in the United States and Canada and potholing in the United Kingdom and Ireland – is the recreational pastime of exploring wild cave systems (as distinguished from show caves). In contrast, speleology i ...
as it allows the load to be spread between two anchor points, reducing the stress placed on them and providing a backup should one fail. Commonly known as the Y-hang it allows for a free-hang descent and can be easily adjusted to avoid waterfalls or rub points.
As mentioned earlier, this knot can replace the figure-eight knot when tying into a climbing harness by tying a regular bowline knot and then re-threading it, such as is done with a figure eight knot. However, it is ''critical'' to use a
strong backup knot with plenty of tail beyond the knot, as the knot may untie during long climbs. The advantage of using this knot instead of the figure eight knot is that it can be easily untied after a severe fall.
Technique
The
bight
The word is derived from Old English ''byht'' (“bend, angle, corner; bay, bight”). In modern English, bight may refer to:
* Bight (geography), recess of a coast, bay, or other curved feature
* Bight (knot), a curved section, slack part, or loo ...
of rope is initially used to make a
bowline
The bowline ( or ) is an ancient and simple knot used to form a fixed loop at the end of a rope. It has the virtues of being both easy to tie and untie; most notably, it is easy to untie after being subjected to a load. The bowline is sometimes ...
in the usual way (picture on right). However, the bowline is ''not'' completed by going on round the standing end(s) and tucking the bight back down beside itself. Instead, the bight is opened up to allow the whole knot to pass through it (see picture on right). When tightened, the bight now embraces the pair of standing ends (see top picture)
Image:Doppelter Palstek-1.jpg, 1
Image:Doppelter Palstek-2.jpg, 2
Image:Doppelter Palstek-3.jpg, 3
Image:Doppelter Palstek.jpg, 4
Image:BowlineBightStep1.jpg, 1
Image:BowlineBightStep2.jpg, 2
Image:BowlineBight.jpg, 3
Notes and references
See also
*
Double bowline
A double bowline (or round turn bowline) is a type of loop knot. Instead of the single turn of the regular bowline, the double bowline uses a round turn. This forms a more secure loop than a standard bowline.
Naming
Though called "double bowlin ...
*
List of knots
This list of knots includes many alternative names for common knots and lashings. Knot names have evolved over time, and there are many conflicting or confusing naming issues. The overhand knot, for example, is also known as the thumb knot. The ...
External links
*
{{Knots
Climbing knots
Double knots
Multi-loop knots