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[Ropemate(Eddie)]

One of These Knots Can Kill You

Posted on September 27, 2016 by David Lottmann

It seems every year we lose climbers to a simple user error that can occur when joining two ropes

 together for a rappel. Compounding the issue is some media outlets refer to the knots (or bends)

 in question with various misnomers that create further confusion within the climbing community.

There needs to be more widespread standardization of the options available for joining two ropes

 together and it starts with referring to them with the correct nomenclature.

The first thing to understand is any knot used to join two ropes together is technically referred to as

 a “bend knot” or simply “bend”. While there are quite a few bends that are appropriate for joining

 two ropes together it is the Flat Overhand Bend that has largely gained popularity for multiple reasons.

Flat Overhand Bend (FOB)

Flat Overhand Bend

Like any option this one comes with advantages and considerations.

Advantages

1. Fast and easy to tie, especially with thick winter gloves on
2. Low profile so less likely to get caught in cracks and on features while pulling the ropes
3. Easy to untie even after a dozen high angle rappels
4. Pull tests indicate a properly tied Flat Overhand Bend will not capsize unless loads exceed at least

         1400 pounds, far more than any climber can generate on a rappel.

Considerations

1. Like any knot this one needs to be “dressed and stressed” to be safe. After forming the knot tighten all 4 strands

         separately.

1. Leave 12 inches (30cms of tail). This is more than sufficient in the unlikely event of the knot capsizing. There has

          been at least one fatality when a cautious climber left 3+ foot tails and then threaded a tail through their belay device e

          nding in catastrophic failure of the system. Twelve inches is sufficient.

1. Use ropes of similar diameter. UIAA recommends within 3mm of each other, which with today’s modern (often skinny)

          ropes is usually easy to stay within. If using a thin tag line consider adding either an overhand tied with the thinner rop

          e over the thicker rope and cinched tight to the flat overhand bend. The idea here is it will help prevent the knot from ca

          psizing but in reality should not be needed. The practice of tying a 2nd flat overhand bend a few inches down from the

          first seems to negate most of the advantages (fast to tie and less likely to get stuck while pulling) so this author feels

          that practice is not needed.

          I’ve made it this far without calling this bend knot by its more common name. I’ve decided to leave the common name

          out. It serves no educational purpose and its use should be considered archaic in nature.

Now we get into the two options that really exacerbate this issue.

One of the two knots below can kill you.

Reverse Traced Figure of Eight Bend (Flemish Bend)

Reverse Traced Figure of Eight Bend

Like any option this one comes with advantages and considerations.

Advantages

1. Low profile so less likely to get caught in cracks and on features while pulling the ropes
2. Super strong. If you look closely you realize this is the same option we use to tie into our harnesses.

          We can not generate enough force to get this knot to fail.

Considerations

1. Like any knot this one needs to be “dressed and stressed” to be safe. After forming the knot tighten all 4 strands

         separately.

     2. Leave 6 inches (15cms of tail). Since this knot can not capsize by design it is logical to follow the same guidelines

         as using the knot to tie into a harness. Six inches of tail on a dressed and stressed knot is sufficient.

     3.  Adding “back-up” knots to both tails greatly increases the likely hood of a stuck rope and is completely unnecessary g

          iven the strength of the main knot.

      4. Can be very difficult to untie after heavy load, especially with gloves on and slick new ropes.

      5.   While tecnhically called the “Flemish Bend” adding the METHOD one uses to create it (reverse traced) to the

           common name will help differientate between the two.

Flat Figure of Eight Bend

Figure of Eight Bend aka FATAL MISTAKE!

The above knot has a proven track record of killing climbers. It routinely capsizes and fails at loads

easily generated in rappelling. So why is it still being used after years of accidents showing it’s not

 sufficient?

New Climber Perception

I’ve had hundreds of new clients look at the FOB (first knot pictured) and say “That’s it?” Having

 confidence that such a simple and quick to tie bend could be sufficient for joining two ropes together and

committing our full body weight out over the abyss is not so easily won. Let’s be honest, its simplicity and

small volume make people nervous regardless of its more than adequate strength.

So what does the new climber do? Well if one twist around the ropes forms a Flat Overhand Bend then two

twists around the ropes must be safer right? That mindset creates the deadly Figure of Eight Bend pictured

above… and kills people.

Misunderstanding

The common name I’ve heard used to describe both the Reverse Traced Figure of Eight (Flemish Bend)

 and the Figure of Eight Bend is the “Flat Eight”.

This needs to stop. One is a strong and suitable bend for rappelling. The other keeps killing people.

We should not use the term “Flat Eight” as most climbers, especially new climbers, do not easily see the

difference between the two. They tie a Figure of Eight Bend, thinking it is a “Flat Eight”.

Solution

In order to reduce or eliminate the amount of fatalities the confusion these options create,

we, the climbing community at large, especially the widely read climbing magazines, need to step up and

standardize our definitions of these knots and not use mis-leading negative sounding catchy names

to describe safe practices. Using misnomers can encourage a new climber to switch to a different,

and potentially much more dangerous option for joining two ropes together.

If every guide, mentor, instructor, and tenured climber starts referring

to these knots with the correct terminology we will see a reduction in

unnecessary loss of life.

[날아라뿅알]

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