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Switching from ascender to descender


You are ascending the rope using a waist prusick & a foot prusick & clove hitch attached to a carabiner on your harness as a back up. You switch to an ATC to descend.

What are the exact steps (in clear simple terms)?

Can you break into the system below the clove hitch & attach the ATC below the clove hitch by pulling up some rope?


There are many schools of thought on this...

One school:

Attach your ATC BELOW your 2 hitches.

Take up all the slack in the down line and tie the ATC off.

Remove the waste hitch from the line first. If you have trouble, you can stand in the leg/foot loop to remove the pressure.

Take your foot out of the bottom hitch and remove it from the line.

Keeping tension on the line w/ your control hand, untie the tie-off knot and begin your descent.


Advanced method:

Attach the ATC BETWEEN the waist and foot prusik. Take up slack.

While maintaining pressure on the line with the foot that is in the foot prusik, remove your waist prusik from the line.

Take control of the down line with your favored hand, remove your foot from the lower prusik loop and remove it from the line with your other hand.


There are various different operations and many orders in which to do this. Most climbing accidents happen while on rappel. IF YOU ARE AT ALL UNSURE, DO NOT TRY THIS on a wall. Ask a professional for help, or take a class.

Just reading along....what is ATC please?

I would make a stronger statement than f_klock's caution - given the wording of the OP's post and the question, I would say DO NOT TRY THIS WITHOUT PROFESSIONAL INSTRUCTION! You can get some excellent written instructions in any of several books on self-rescue. But you really should have someone very experienced in this procedure watch you closely and supervise until you get the many tricky points down pat. It is very easy to make a minor mistake with major consequences. As f_klock states, most climbing accidents happen on rappel. Doing a complex maneuver such as the changeover described has far too many steps that could be missed, resulting in a serious fall.

"ATC" is Black Diamond's name for their descender series. Originally it stood for "Air Traffic Controller". There are now 3 versions in the series, ranging from a basic one (ATC) to one with some refinements to deal with the ever shrinking diameter of climbing ropes (the ATC XP) to the ATC Guide, which is intended for professional guides and others with extensive experience.

As f_klock uses it, he is referring to descending devices generically, whether by BD, Petzl, Omega Pacific, Trango, etc etc. This range of different devices is one of the reasons I caution anyone trying to do what he OP is describing to make use of a professional guide or at least someone very experienced in climbing self-rescue.


Switching over from ascent to rappel IS COMPLICATED AND EXTREMELY DANGEROUS. Adventure racers that do this sort of thing all the time must take a low-level skills test to prove they are capable of performing this operation effectively before they are allowed to race.

There are many different ways to accomplish this task - some are safer than others, and some are downright deadly. As a rescue technician and recreational tree climber, I've probably done this operation 200 times or more. When I went to Utah for the Primal Quest race, master climber Jay Smith showed me some techniques that I had never seen before. Though efficient, they were very different from what I had been taught and had practiced for years. Bottom line...Do what you feel comfortable doing. Don't try something new, that you're not familiar with (gear or technique) until you've practiced it LOW TO THE GROUND many times, and are proficient at it.

Gear: There are a multitude of belay/ascent/descent devices out there that basically do the same things. The problem is, each one has some variable that sets it apart from the the others. Sometimes the same operation can be accomplished in exactly the same way using two completely different pieces of equipment. On the other hand, rigging two different, but seemingly similar, pieces of gear in a similar manner can have disastrous results. Know your gear well.

Always read the manufacturer's instructions and get professional instruction before trying new gear or techniques.

Somewhat related technique ...

Always good to have alternative methods to the usual way you do something.

November 28, 2020
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