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gus
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Rope? Question for the climbers?
A while back I bought a 100m of static (abseiling) rope that I thought I'd keep in the car along with a few other bits and pieces that would be useful for rescue scenarios, most likely wire strikes / hangups. Trouble is, the rope's 10 or 11 mm in diameter and it'd be a real pain to haul it up (for example) a tight internal ladder.
So does anyone have any opinions on something like this? It's 5mm diameter, static and has a breaking strain of 5.5kN. It doesn't need to take falls, just suspsend someone's weight and maybe allow them to ascend or descend.
Or am I just barking up the wrong bush?

Gus
Sean621
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Re: [gus] Rope? Question for the climbers?
not sure the rope diameter is the issue mate...the descender device,(gris gris,reverso or what ever )would be the sticking point with that diameter rope...you ould onlly need to haulone end up though...then drag the rest up afterwards.
gus
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Re: [Sean621] Rope? Question for the climbers?
Yeah I thought that it might be too thin for normal ascenders or descenders but that's secondary to whether it's safe to simply suspend someone's weight.

Gus
Sean621
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Re: [gus] Rope? Question for the climbers?
slowly controlled lowering...youve then got to factor in all variables like them falling off whatever they are hung on...ie snatch force...the rope is more than enough to carry someones weight...
DexterBase
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Re: [gus] Rope? Question for the climbers?
It should be adequately strong, technically, but you're going to have a seriously hard time working with it.

Like previously mentioned, there are currently no ascenders or descending devices available for such a small diameter line.

8mm cord is about the smallest practical rope diameter for ascending or descending.

Go look at some 8mm static line. Sterling ropes makes some incredibly strong thin stuff. It's super lightweight and is thin enough to really freak you out of you're hanging high off the ground with the stuff.
Sean621
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Re: [DexterBase] Rope? Question for the climbers?
5.5kN is around 1250 lbs force...
base915
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Re: [gus] Rope? Question for the climbers?
There are some ultra light, and thin, single dynamic ropes on the market - like the Mammut - Revelation 9.2mm - which would be lighter than the static rope you have. Great for sports climbing but in a rescue situation I would deffo prefer the 11mm static. Two would be better, a working rope and a backup (OK, that's maybe a bit OTT).
I recon it's OK to sweat a little on the climb Wink and carry a stronger rope or two. You could concievably be loading the rope with two persons plus base gear, you and the rescuee will feel a lot better if dangling on a rope rather than a string. Also, you would have to look at the hardware you intend to use with the rope. For example; the abseil device you would use for descending to the 'casualty', and possibly with the casualty attached to you. Will it work; i.e provide enough friction to slow you (both) down. You may need to consider adding more friction into the system; an extra karabiner attached to your harness leg loop should do the trick. Clip the free end of the abseil rope through the karabiner after the abseil device to add another friction corner to the system.
And remember any knot you tie in the system will reduce the breaking strain of the rope. Even the best figure of eight or figure of nine knots will reduce breaking strains by up to ~20%.

Look at 'Life On A Line' for rescue and rope access techniques. This is primarily a resource for cavers but the techniques have also been adapted for use in industrial rope access.

http://www.draftlight.net/lifeonaline/download/

http://www.irata.org/


Cheers.
Mike.
gus
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Re: [base915] Rope? Question for the climbers?
I had thought about the possibility of having more than one person on the rope but to be honest I'm not familiar enough with those kind of techniques. More than likely I would make things worse. The very basic idea that I had was to lower one end of the rope to the stranded jumper, with a figure of 8 knot and a carabiner and have them clip the carabiner through their harness. Then I take up the slack and secure the rope to the antenna. Now at least they have some security. From there they either cut away the canopy and swing in to the antenna (if I've tied the other end a good height above them I think this is feasible) or simply wait for professional help.

Thanks for the links they look interesting.

Gus
Sean621
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Re: [gus] Rope? Question for the climbers?
theres 450 feet of static rope at mine if you need it mate...Blush
DexterBase
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Re: [gus] Rope? Question for the climbers?
In this application, the thin cord would be totally fine. You're going to have a hard time if you try to lower them, just because the line is super thin, but if you're just trying to secure them from falling further, you should be cool.
base915
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Re: [gus] Rope? Question for the climbers?
Gus

'Life on a line' is 3 downloadable pdf documents and is superb. Well worth reading for rope rescue stuff.

If I read you right, you want to recover someone from a hang up on a guy wire with minimal kit and personnel? What if they are unconscious, and if they weren't injured initialy they may be after the swing to the antenna?

I've never done this, it's just my thoughts and open to critique:

The rope should be as long as the guy wire, you could use two or three ropes joined with double fishermans knots (lot of stretch though and you need to have two belay devices for passing the knots)
Secure the rope to the antenna at the top of the wire and abseil down the wire to them, use a sling round the wire for this. When you get to a point above them, just before the canopy wrapped round the wire. Use another sling in a larks head choked round the wire, clip the working rope (the rope under tension) to this with a karabiner (you now have a rebelay), remove the sliding sling and try to clip this through as many of the parachute lines as poss and to your harness anchor point. The hung up jumper is now secure (ish).
Now abseil down verticaly to level with the (unfortunate) jumper lock off your abseil device and swing accross till you can grab or wrap your legs roun them. Attach them to you probably via largest of the three rings (both) and either cut the parachute away or cut the lines.
You should now both be suspended from the rope and free to abseil to the ground (if the rope is long enough. Remember the extra friction point for the extra weight.

Also be aware of suspension trauma. An unconscious but live casualty hanging in a harness can be killed by being released from suspension. I.E layed on the ground. Blood pooled in the large muscles of the legs will build up metabolic toxins and overload the system when released, causing death. (I'll try to find the artical on this). The casualty only has to be hanging immobile for 20mins for this to happen but that time varies per person.

This is my humble opinion only, apart from the suspension trauma, that's fact.

Comments?


Mike
gus
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Re: [base915] Rope? Question for the climbers?
In reply to:
If I read you right, you want to recover someone from a hang up on a guy wire with minimal kit and personnel? What if they are unconscious, and if they weren't injured initialy they may be after the swing to the antenna?

Basically I want to be able to do something useful even if it's just to secure the jumper whilst the pros turn up. But even that is sounding more and more complicated with my limited rope skills, limited personnel and limited equipment.

It's been a while since I did any physics but I reckon an 80 kg jumper on the end of a 50 m rope making a 45 degree angle with the antenna will hit the antenna at 17 m/s which is about 40 mph Unsure. So even that idea is sounding bad.

Gus
TomAiello
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Re: [base915] Rope? Question for the climbers?
In reply to:
You should now both be suspended from the rope and free to abseil to the ground.

If you take an extra length of line, you can also just pull yourself (and the injured person) across to the main structure. This is a good backup plan if the rope won't reach the ground, but will leave you having to rig a series of rappels down the tower to get the jumper to the ground.
crwper
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Re: [gus] Rope? Question for the climbers?
Something else you might want to think about (I hope someone with more climbing experience will comment on this): It seems to me that a smaller-diameter cord would be more prone to overheating or abrasion due to friction (or possibly even due to stretch in the cord). As has already been mentioned, this stuff will probably do fine in a perfectly static situation, but be careful using it where movement is involved.

Michael
TomAiello
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Re: [crwper] Rope? Question for the climbers?
If you guys want good answers to these kind of questions, I've found that the folks at many rope manufacturers are quite helpful, and usually available to answer questions.
321Cya
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Re: [base915] Rope? Question for the climbers?
In reply to:
There are some ultra light, and thin, single dynamic ropes on the market - like the Mammut - Revelation 9.2mm - which would be lighter than the static rope you have. Great for sports climbing but in a rescue situation I would deffo prefer the 11mm static. Two would be better, a working rope and a backup (OK, that's maybe a bit OTT).
I recon it's OK to sweat a little on the climb and carry a stronger rope or two. You could concievably be loading the rope with two persons plus base gear, you and the rescuee will feel a lot better if dangling on a rope rather than a string. Also, you would have to look at the hardware you intend to use with the rope. For example; the abseil device you would use for descending to the 'casualty', and possibly with the casualty attached to you. Will it work; i.e provide enough friction to slow you (both) down. You may need to consider adding more friction into the system; an extra karabiner attached to your harness leg loop should do the trick. Clip the free end of the abseil rope through the karabiner after the abseil device to add another friction corner to the system.
And remember any knot you tie in the system will reduce the breaking strain of the rope. Even the best figure of eight or figure of nine knots will reduce breaking strains by up to ~20%.

Look at 'Life On A Line' for rescue and rope access techniques. This is primarily a resource for cavers but the techniques have also been adapted for use in industrial rope access.

http://www.draftlight.net/lifeonaline/download/

http://www.irata.org/


Cheers.
Mike.

Gus

'Life on a line' is 3 downloadable pdf documents and is superb. Well worth reading for rope rescue stuff.

If I read you right, you want to recover someone from a hang up on a guy wire with minimal kit and personnel? What if they are unconscious, and if they weren't injured initialy they may be after the swing to the antenna?

I've never done this, it's just my thoughts and open to critique:

The rope should be as long as the guy wire, you could use two or three ropes joined with double fishermans knots (lot of stretch though and you need to have two belay devices for passing the knots)
Secure the rope to the antenna at the top of the wire and abseil down the wire to them, use a sling round the wire for this. When you get to a point above them, just before the canopy wrapped round the wire. Use another sling in a larks head choked round the wire, clip the working rope (the rope under tension) to this with a karabiner (you now have a rebelay), remove the sliding sling and try to clip this through as many of the parachute lines as poss and to your harness anchor point. The hung up jumper is now secure (ish).
Now abseil down verticaly to level with the (unfortunate) jumper lock off your abseil device and swing accross till you can grab or wrap your legs roun them. Attach them to you probably via largest of the three rings (both) and either cut the parachute away or cut the lines.
You should now both be suspended from the rope and free to abseil to the ground (if the rope is long enough. Remember the extra friction point for the extra weight.

Also be aware of suspension trauma. An unconscious but live casualty hanging in a harness can be killed by being released from suspension. I.E layed on the ground. Blood pooled in the large muscles of the legs will build up metabolic toxins and overload the system when released, causing death. (I'll try to find the artical on this). The casualty only has to be hanging immobile for 20mins for this to happen but that time varies per person.

This is my humble opinion only, apart from the suspension trauma, that's fact.

Comments?


Mike

Sounds like a fresh Level II to me... Congrats on that one bro! Well done. Smile

Also looks like somebody is offshore at the moment...Tongue

Cya,

J.
base915
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Re: [321Cya] Rope? Question for the climbers?
Oh Yes. Very, very 'offshore'! You know what I mean Blue Tongue. Are you staying out of the smokers T shack?

That's why I reply to emails within 3 seconds and monitor three BASE forums at once Wink

Yup, a brand new Level 2 rope access monkey.

BTW. I don't think returning to the antenna is a good idea. Just makes the rescue more difficult. It is possible to do the whole rescue with one rope and a few slings leaving at most one sling behind on the guy wire. You can work your way down the guy wire with choked soft slings. Then abseil to the casualty etc etc..
321Cya
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Re: [base915] Rope? Question for the climbers?
In reply to:
Are you staying out of the smokers T shack?

Make that T shack... Gave up on the bad habit dude Smile

Looking forward to do the mushroom together bro... Prepare for a quick hike up Wink
TomDancs
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Re: [gus] Rope? Question for the climbers?
Hi Gus,

Glad to see that you are thinking about rescue situations. I am a climbing guide, and as such have taught many vertical/high angle rescue courses to climbers and to local mountain rescue groups.

Your concern about rope diameter is legitimate, but should be taken into consideration with regard to your intended goal.

If your intent is simply to secure a victim to the structure to and wait until high angle rescue arrives, the thinner cord will likely be adequate, as long as you can protect from sharp edges, and you have the additional gear and knowledge for building secure anchors.

If your intent is to execute a high angle rescue without outside intervention, you will need thicker ropes, and additional equipment, but most importantly training. In most BASE scenarios I can think of, your rescue goal would play out as follows:

1.) First get to the victim (preferably from above).
2.) Ensure scene safety (i.e., secure the victim, and yourself, as to prevent another accident).
3.) Assess the victim, and administer the needed first aid. In some cases you will come to the conclusion that it is unsafe to move the victim because of injuries that could be further compounded due to the somewhat rough nature of self rescue, and lack of a rescue litter/basket.
4.) If you decide that you can continue your rescue, you will re-rig to a counterbalanced or tandem rappel situation, and may have to do multiple rappels, depending on the height of the object, the length of your rope(s), and the availability of appropriate anchor points and equipment.
5.) Once you have reached solid ground, you would further stabilize your victim, and decide on the best alternative for further transport. At this point you could presumably have more people help out.

That said, none of this works, with out good first aid training; high angle self rescue training, the correct equipment, a solid plan of action, and good judgment.

You should be able to contact different reputable organizations in the UK for both First Responder and High Angle Rescue Training. I would suggest being honest with your trainers about BASE, explain to them the limitations in man power and equipment, and ask them to tailor a course for a group of BASE jumpers.

Yes it will cost you, but it will be fun for you and your friends, and it could cost you a whole lot less in the long run.

Safety First!

Tom Dancs
Calvin19
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Re: [gus] Rope? Question for the climbers?
keep in mind,
there is a lot of rope out there that is not even used by climbers/rescuers that is perfect for this,

some stuff i would recommend is not even kernmantle,

there is no rules here, we are trying to make progress right?
councilman24
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Re: [base915] Rope? Question for the climbers?
In reply to:
Gus

Secure the rope to the antenna at the top of the wire and abseil down the wire to them, use a sling round the wire for this. When you get to a point above them, just before the canopy wrapped round the wire. Use another sling in a larks head choked round the wire, clip the working rope (the rope under tension) to this with a karabiner (you now have a rebelay), remove the sliding sling and try to clip this through as many of the parachute lines as poss and to your harness anchor point. The hung up jumper is now secure (ish).
Now abseil down verticaly to level with the (unfortunate) jumper lock off your abseil device and swing accross till you can grab or wrap your legs roun them. Attach them to you probably via largest of the three rings (both) and either cut the parachute away or cut the lines.
You should now both be suspended from the rope and free to abseil to the ground (if the rope is long enough. Remember the extra friction point for the extra weight.



Mike

As some one trained in confined space/high angle rescue there's some problems here.

One "use a sling round the wire for this"

This sling isn't going to last long loaded and sliding down a wire. Then you swing into the tower and if you don't fall you have two potential victims. IF I was trying to improvise this I might use a pulley instead of a sling.

"Use another sling in a larks head choked round the wire, clip the working rope (the rope under tension) to this with a karabiner (you now have a rebelay),"

Your trying to transfer the load from one anchor to another. Sling to Sling To do this you have to be able to take the load off. Not to mention the larks headed sling may or may not hold on a wire cable. What happens when you find yourself with the sling sliding down, again being cut and you out of control?

Getting the "victim" onto your harness and repelling with both is not an easy task. I practiced this two weeks ago with the proper gear. Also, you may or may not have enough friction for the two person load depending on what you chose. We use 6 bar racks.

The idea of jumper rescue is not a very good idea. You really need to be trained professionally and practice routinely. Even then, trying to figure this one out in the heat of a jump situation is dicey.

But, also don't depend on the locals to have experts. In my area the largest city (75,000) stopped training and doing high angle rescues. The second largest city (45,000) does train their fire dept. on high angle rescue but this would be an extraordinaty situation not trained for. The company I work for is mandated to maintain rescue capability (hence my training) but we don't practice enough to be very good, and have varying levels of training. Probably the best trained locals might be the Ski Patrol for chair lift evacuation but probably not easily available.

Don't play at figuring this out. I'd suggest securing somebody rather than attempting rescue.

When I landed in a tree half way up a ski slope and was 40' in the air with a shattered leg, I had to direct the rescue. The fire guys didn't have a clue what to do. Not their fault.
stuntedflyer
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Re: [base915] Rope? Question for the climbers?
Alright,

Maybe a new thread needs starting, but how many others into BASE have a rope access qual??? Preferably irata!!??

In response to the original post, maybe you should consider hooking up with one of the rope-access qualified guys for some basic tips and training....

Just my two cents worth from down under...

p.s. Yes I have an irata ticket and would love to assist any toasters with access... however somebody stole all my gear (not mentioning any names of course)
base915
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Re: [councilman24] Rope? Question for the climbers?
"This sling isn't going to last long loaded and sliding down a wire. Then you swing into the tower and if you don't fall you have two potential victims. IF I was trying to improvise this I might use a pulley instead of a sling."

Depends what type of sling you use and how fast you abseil. The main load is on the abseil rope, the sling is just to keep you next to the wire. There will be friction so maybe use a steel wire strop or a rope protector round the sling. I don't recon you will find a pulley big enough, not easily anyway.

"Your trying to transfer the load from one anchor to another. Sling to Sling To do this you have to be able to take the load off. Not to mention the larks headed sling may or may not hold on a wire cable. What happens when you find yourself with the sling sliding down, again being cut and you out of control?
"

In the situation I was describing the rope stays anchored to the antenna at the head of the guy wire. All you are doing is putting in a re-belay. If you think a larks head will slip add another turn to the knot and hey presto you have a prussik knot which won't slip (even if it did, the forces on it would push it back up the guy wire and not very fast at all). Add the rebelay to the tensioned rope above your belay device, no effort required, then all you have to do is pull yourself a little closer to the wire and unclip the sliding sling from your harness and ease yourself on to the rebelay. 1 or 2 foot at most.

Getting the "victim" onto your harness and repelling with both is not an easy task. I practiced this two weeks ago with the proper gear. Also, you may or may not have enough friction for the two person load depending on what you chose. We use 6 bar racks.

In this situation getting the victim attached to your harness is easy. If you abseil down till you are level with their head, lock off the stop or ID, clip a quick draw onto each of the large rings on their BASE harness and to your harness belay anchor point. Then cut their lines or use the cut away to get them on to your harness, they will hang from your main anchor point between your legs. For abseiling I'd use a petzel stop or an 'ID' with the tail round a karabiner on your leg loop for extra friction. This is relatively easy compared to a mid rope rescue from a croll or other ascending device. No counterbalance or pulley systems required.

I do agree that training would be a good idea. The IRATA L1 course would be good. Plenty of rescues, knots, rebelays, etc in that.
Sean621
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Re: [gus] Rope? Question for the climbers?
some info that may be of interest

http://www.narc.co.uk/

The National Access and Rescue Centre
LDBP, Mintbridge Rd.
Kendal
Cumbria
LA9 6NH
phone and fax numbers:
tel: 01539 728866
fax: 01539 728833
op5e
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Re: Rope? Question for the climbers?
I have to say I do not have much knowledge of this area.

I did find the below link (in the appendix) helped me understand how much I did not know about ropes. Any more good resources about knots that would be useful or similar information.

http://www.petzl.com/...log/sp/SP2005_EN.pdf