What is the best way to belay a rappeler? Petzl ASAP?

[Ch33s3n1p]

I occasionally lead rappelling (above ground) trips with a few friends with some vertical experience, but not enough to make me feel comfortable leaving them on their own. In the past, I would rappel first a provide a "fireman's" belay while another experienced person verified each rappeller's equipment was connected properly before going over the edge. I am interested in trying a running belay on a second rope with the Petzl ASAP or a similar fall arrestor. Does anyone have experience with the ASAP or any similar product? At what speed does the ASAP "lock"? Would there be a possibility of the device locking at normal rappelling speeds? The primary use would be above ground, so I'm not concerned about potential problems with a muddy rope or muddy device. As long as folks need a belay, we won't be going in cave.

Of course I would need to consider how to lower the belay line when the ASAP does lock. That is something I'm already familliar with and I'm not looking for advice on that topic.

Thanks in advance for any input.

[Ch33s3n1p]

Also, would the Petzl ASAP function correctly on the same line you are rappelling on? Maybe extended 12" above your descender or attached on the other side of the descender and connected to a leg loop?

[snoboy]

I am interested in trying a running belay on a second rope with the Petzl ASAP or a similar fall arrestor. Does anyone have experience with the ASAP or any similar product?

Yes. I have used the ASAP, the DMM Buddy, and the Kong Backup. The ASAP works well in all orientations, the other two work best when the rope is vertical or very close to vertical but they tend to lock when the rope is sloped.

At what speed does the ASAP "lock"?

Can't remember exactly, it's in the specs somewhere.

Would there be a possibility of the device locking at normal rappelling speeds?

No, this is what it's designed for. It works well.

I can't imagine that using it as an autoblock attached to the leg loop would be very practical, it's bigger than you might imagine if you haven't seen it in person yet.

I believe that people have used the ASAP on the same line as the rappel device, but that is not the designed intent.

[Tim White]

The Petzl Technical Notice for the ASAP is:
http://www.petzl.com/files/all/technica ... 1-ASAP.pdf

You can find many of your answers there.

I have to disagree with snoboy regarding possibility of a lock-up under “normal rappel speed”. (Guess we need to define what that is… NSS Vertical Section's Basic SRT class says “Less than 1 meter per second.”)
Having been a part of having over 20,000 people rappel using the ASAP, I can tell you for a FACT, that it does lock-up under “normal rappel speed”. That speed is NOT the Vertical Section’s less than 1 meter per second, but still not a fast rate.

Read and follow the Technical Notice for lanyard attachment, etc.

[Ch33s3n1p]

Yes. I have used the ASAP, the DMM Buddy, and the Kong Backup. The ASAP works well in all orientations, the other two work best when the rope is vertical or very close to vertical but they tend to lock when the rope is sloped.

Thanks for the insight on the different devices. I would be using the device for vertical, free hanging rappels. It seems like for my purposes, the DMM Buddy or Kong Backup will do the job fine for less than half the cost of the Petzl ASAP.

Is releasing these devices as simple as just climbing up a couple feet to relieve tension and just disengaging a cam?

[hank moon]

Your current setup sounds good - why not stick with the fireman's? I would not use the ASAP as it requires a second line (best not to use it on the rap line - not designed for that), and is really expensive, and may not work as desired (might complicate the fun and/or be dangerous). Note that backup devices are generally for experienced users, not beginners. There is no substitute for a good belay, when rap skills are lacking.

[snoboy]

I have to disagree with snoboy regarding possibility of a lock-up under “normal rappel speed”. (Guess we need to define what that is… NSS Vertical Section's Basic SRT class says “Less than 1 meter per second.”)

I think it would come down to the definition. I have never had one lock up at what I consider normal... I had a closer look a the documentation and I don't see a speed mentioned anywhere by Petzl.

[hank moon]

This is from the RIG instructions - FYI.

[cavedoc]

it does lock-up under “normal rappel speed”.

Had to use it once in Tim's OTE scenario. It caught several times at slow rappel speeds. In the OP's scenario, it may cause more problems than it solves if the novice rappeler now needs to have to deal with it and doesn't have the tools to do it.

[hank moon]

In the OP's scenario, it may cause more problems than it solves if the novice rappeler now needs to have to deal with it and doesn't have the tools to do it.

^ ^ ^ ^ ^
yes, this

[NZcaver]

it does lock-up under “normal rappel speed”.

Had to use it once in Tim's OTE scenario. It caught several times at slow rappel speeds. In the OP's scenario, it may cause more problems than it solves if the novice rappeler now needs to have to deal with it and doesn't have the tools to do it.

I agree the ASAP can lock up at relatively slow rappelling speeds. I have a helmet cam video of myself gradually increasing my speed on a building rappel until the ASAP locked up when I reached about 1 meter per second descent speed.

If the ASAP locks, you obviously need to have a procedure in place for unlocking it. One option is to rig the safety/belay line releasable through a descender, and have somebody at the top managing that. They only need to lower a foot of rope or so to release the ASAP, depending on rope length and stretch. Otherwise the person on rope needs to lock their descender and use an ascender with footloop to briefly transfer weight off the ASAP (It only needs to go up and inch or so to release).

A better plan is to either stick with single rope and a bottom belay if that works for you (keep it simple), or introduce a second belay rope connected to the rappeller and have somebody at the top manage this through a fixed descender or Munter hitch. I use one or other (or both) of these methods with beginners, depending on the circumstances. Just be aware than when you introduce a second rope you need to think about the ropes possibly twisting together, especially on a free hanging drop. Your belayer needs to be experienced, and ideally in a position hanging over the edge so they can see and hear what is going on below.

[Foxy.Ferguson]

I don't think there is a "best" way because a lot depends on the type of rappel system the person uses. The belay-from-below that we employed in TAG 'way back when would not at all work on those who used bobbins as they existed then. Whether or not they'd work with the current offerings, I cannot say, having nothing but devices that pre-date 1975 in my collection. But those of us in TAG in the 60's and 70's consistently followed a system of each person down a pit giving a belay-from-below to the next, even knowing how experienced all of us on a particular trip may have been as well as the fact that most of us used the Cole Rack as our primary descent device.