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Flat overhand bend - how long a tail?

John Godino

A great knot choice to connect to rappel ropes for a double strand rappel is the flat overhand bend. (It was previously known by some as the “European Death Knot”, or EDK. Let's not call it that anymore, okay?)

Why is this a good rappel knot?

  • It’s known as an “offset” knot, because the body of the knot is offset from the line of pull. This can help the knot work its way around obstructions such as rock nubbins or ledges to lessen the chance of it getting hung up when you pull your rope.

  • Works well with ropes of different diameters (up to about 3mm difference). So if you want to connect a skinny 7.7 twin rope with a 9.5 single rope, no worries.

  • Super easy to tie and visually check.

  • It's plenty strong for any normal two strand rappel situation. (For a single rope rappels more common in caving and canyoneering, or for extra heavy loads, some recent research recommends a more robust knot. We’ll cover that in a future tip.)

It’s important to have the right amount of tail in the flat overhand bend. A good rule of thumb is about 30 cm / 1 foot.

Think of that as about the length of your forearm, or two hand spans. It's sort of the Goldilocks length, not too short and not too long. This length gives you a margin of error to prevent minor mistakes from becoming catastrophic.

  • If the tails are too short, the knot could potentially roll once or twice under an extremely heavy load and roll off the ends. A decent sized tail (hopefully) prevent this.

  • If you tie a sloppy, poorly dressed knot, a proper tail allows the knot to tighten up under load without pulling in the ends.

  • Not-too-long tails give you use of the full rope, which can be important in reaching the next rappel station if it's a real rope stretcher and you need every possible meter.

  • Proper length tails keep your nervous partner happy, and gives them room to add another overhand knot (aka stacked flat overhand bend) in the tail if they like, to give them a warm fuzzy feeling before they rappel. =^)

  • Many people think a longer tail is better. Not so. If the tails are too long, it increases the chance of someone mistakenly clipping their rappel device to the tails rather than the actual rope. While you may think this would never happen to you, this has caused fatal accidents to extremely experienced climbers, usually in darkness and/or from major exhaustion. Eliminate this potential mistake by having tails not too long, but just right.

  • If for some reason you’re ever fixing a rope (or using someone else's fixed rope) or tying two together like this, and the tails are longer than about 30 cm, at the very least tie a stopper knot in the ends, or tie them together, or do something to prevent someone from ever rapping off the ends.

Here are two accounts of tragic accidents where someone rigged a fixed rope with a long tail, and rappelled off the tail instead of the actual rope.