UKC

Hoping that I don't get shot down for asking this question!

I'm planning on taking a small group of friends and family for abseiling at a nearby crag and I was just wondering how bad it would be to use a standard multi-pitch bail-out type abseil setup for a group of newbies. I would be using a 10.1 mm dynamic rope on a bomber redundant anchor with a standard belay device backed up by a prussik.

But I don't have a second rope to use as a safety rope controlled by myself so they would be self-reliant once they're off. I know them well and I know they are sensible/won't panic etc and I would make sure loose clothing/hair etc is tied away appropriately.

I'm guessing some people will always say why risk it but I'm just trying to judge if that is the majority viewpoint. My view is that you are a bit stuffed if something does go wrong but it is extremely unlikely and I'm happy to accept the risk, after fully briefing my friends.

In reply to s1362083:

Can you have someone at the bottom to lock it off from there?

In reply to s1362083:

How long's your rope? Can you not double it and belay them on the other strand?

In reply to s1362083:

Or failing that, as mentioned above have someone on the ground to belay from below by pulling on the rope if it all goes wrong.

In reply to s1362083:

If you really haven't another rope and your single rope isn't long enough to double as safety as well as ab rope and you don't have or trust someone to hold the ropes below then you could stack the abseilers at the top then descend and hold the ropes yourself.

In reply to Oceanrower:


This.

I wouldn't want the faff of a Prusik with beginners.

I did think about that but I ruled it out on account of it being more important that I'm at the top making sure the belay and prussik are put on properly. However, I suppose anyone can pull the rope from below so I'll make sure we have someone at the bottom to do the job.

In reply to jezb1:

Good point, I could do away with the prussik entirely in this case.

In reply to s1362083:

The two best alternative methods to a second rope for backing up an abseil have been mentioned already.

1. Double the rope and secure with top rope method (my personal choice).

2. Have a fireman's belay at the bottom (dead-man's hand).

I would recommend the first method as you still have the ability to perform rescues requiring unweighting the rope and do not need a second person.

I cannot under any circumstance recommend using just a prussik backup with novices - too much room for error and ultimately, catastrophe.

Perhaps a tandem abseil if you are confident in setting it up and problem solving on the way down?

Merry Christmas and a Happy New Year. Stay safe out there.

In reply to s1362083:

By multi-pitch bailout set up do you mean a retrievable abseil? If so, rather than just clipping the rope through the anchor point, tie a figure of eight on a bight at the middle of the rope and clip it to the central point of the anchor with a screwgate (admittedly this assumes that the rope is not needed in the set up of the anchor), one strand can be used to abseil on and the other used as a safety back up. This allows you to supervise people setting themselves up to abseil, have them backed up and also able to move the weight off their belay plate if they get hair etc stuck.

In reply to s1362083:

If it's a single pitch crag then why not just set up a releasable abseil? I don't see what you are gaining by doing a retrievable one other than a load of faff. That said, if you must do the latter then make sure they know how to clip the belay on and do a fireman's belay. No Prussik needed that way.

In reply to s1362083:
You could maybe buy or borrow another rope?

In reply to spenser:

The place I have in mind is around 30m so I'll do as Spenser says if it is within 30m and resort to a fireman's belay if longer. Will set up a retrievable abseil in either case and get rid of the prusik.

Thanks for the help everyone!

In reply to s1362083:

I recall either in On Rope or Alpine Caving Techniques a discussion about protecting abseils. They were of the opinion that a second rope top rope top belay style was more of a cluster than it was worth. If you do opt for this method, you're going to have to pull the safety up rope for each abseiler which is more faff (also it'll mean people will abseil single strand instead of double, so may find it a bit harder to control). If it were me I'd go with a fireman's belay with someone who had done it before at the bottom. That first person down could have a prussik, or a top belay, no one else though.

My caving club around here does a fair amount of SRT practice. We use racks or bobbins, and semistatic lines, if someone's never abseiled before they'll get a firemans belay the first night. After that, no firemans belay and no prussik is the usual. It's interesting as they're more safety conscious than climbers on the whole. The system does admittedly have notably more friction in it when using the racks.

Regardless of what you do I think everyone having a cows tail and weighting everything before disconnecting, is a good idea.

In reply to s1362083:

I've done this with someone at the bottom for safety, but the 1st time abseiler went upside down! It ended ok, but it looked like he could have dropped out of the harness. Make sure the abseiler can't drop out of the harness. Maybe you can adapt a sling to use as a chest harness.