The Prusik knot. Where would kite-fliers be without this great
shiftable, lockable knot... A bit of a pain to tie at first, but it
makes adjusting a bridle so easy!
Pulling the bridle straight unlocks the knot, letting you shift it
along the bridle line. Pulling on the lines as pairs as in the last
photo causes the knot to fold, locking it in place.
I use the Prusik on horizontal bridle loops to shift the knot left or right across
the kite, for trimming purposes. More commonly, it's also used to slide
up and down the bridle line of, say, a Diamond kite to adjust the
Towing Point fore and aft.
On kites with 4 legged bridles, arranged as an upper and lower
loop plus a connecting line, this means 3 shiftable knots. For example,
the Dowel Rokkaku and Dopero. At least you only have to tie these knots
Although it seemed a little excessive at the time, I took this approach on
even my smallest Dopero. A tiny kite with a 30cm (12") wingspan. But it
sure paid off, since some fiddling was required to get a decent flight
out of it!
More recently, I have also used this knot on the vertical bridle
loops of a large Genki. Same deal, tiny adjustments can trim the kite
left or right.
In the video below (which takes 22 seconds to get started!), I take it slow, showing how to tie, lock, unlock and shift the Prusik. Note also how I first tie a Simple knot to prevent the loose end from ever pulling through...
There are other ways, some possibly a little simpler, to obtain a shiftable knot. However, the Prusik has worked so well for me over the years that it's the one I would recommend.
This mountaineering knot was invented in 1931 by Dr. Karl Prusik. With one 's'. At least this
web-master has finally got it right. Many others still haven't! Prusik
later authored a mountaineering manual, which was the first publication
to feature this well-known sliding knot.
Tying a Prusik knot actually becomes fun after a while, funnily
enough! Be sure to put a Simple knot into the short end of the line
though, since constant use tends to pull line through the knot. The
short end gets noticeably shorter than you remember tying it originally.
Perhaps this happens during locking and unlocking.
Knowing your knots is particularly handy if you make your own kites at home...
The Big MBK Book Bundle is a collection of downloads - printable PDF files which provide step-by-step instructions for many kites large and small.