The longest leader fall I have ever witnessed, was dern near a 100' on a single 9mmx100m and guess what, it held. I have never heard of a rope breaking during a climbing fall, cut yes but not just breaking. I climb regulary on a single double rope and have in the past used just a single twin.

I agree more with Brutus. But, talking or reporting about climbing skills is hard at best and things get chaboni'd up in the meaning. (Thats why reading books on skills has little do to with real climbing) Climbing is not black and white, there is lots of gray.

No matter how you put it, a double rope system has the least impact force and when use correctly, the other rope backs this up by the phyics of dynamic ropes stretching making it the safest.

For ice / alpine climbing, which I know little about, you just cant report how to use a rope system and how it applies to all skills, at least give insight on how to do it right if you must report it. For double / half ropes with I use primarly, just off the belay, you clip both ropes into a piece to protect the belay, not just a single strand, then clip alt maybe, the line will determine, then ever so often like after clipping each strand once, you clip both strands either into a single bomber or use a screamer on a single piece or if you know how its done, you put two pieces real close to each other and clip 1 strand into just one piece. When using double ropes, clipping each stand into its own piece is done but the two peices are or should be sort of close together, not 50' apart. I know what has been seen and been told but, most climbing rag stars are not that gifted at doing it correctly or safely. Just look at the French in Pata mag, how unsafe can you be! Everybody can pull down M9 these days but nobody knows how to build a safe belay or even climb that safely!! In fact, most guides are confussed and teaching improper skills.

Oh well back to being the chaboni I am , it has been a grand year of ice climbing for me, I finaly led grade 3 ice, OK it was cheater ice is the sun and +35f but I made it and even TR'd grade 4 but I did fall 2 times. Someday I will be a hero.

-10F tonight, spring is here!!!

However, in a half-rope setup,
the higher the fall factor,
the more the second rope shares in the load,
regardless of the length of runout between
pieces. It is a directly-porportional
relationship.

I believe that failure of a single
strand in runout situations MAY be a
valid concern, so I clip both in to
bomber pieces. But I do not agree with
Mr. Microy's ultimate conclusion.

> The twin rope was designed to be
> used in the double strand and both
> strands must be clipped in every
> runner. Generally these ropes have a
> diameter of only 8 mm.

Less, for the Ice Floss.

> The benefit of a twin rope is its
> essential safety and the advantage
> in the mountains for a full length rappel.

same benefit for two half-ropes.

> A half rope used singly is, therefore,
> much more likely to be cut than
> a single rope.

duh. but it is backed up by the second strand,
same as the twin rope. I know of no one who
recommends using a half rope singly on vertical
terrain, and to do so is not in accordance with
its intended uses. Mr. Microy is setting up
"straw men" for targets then shooting them down
to impress us. I'm not impressed. Let's continue:

> It could potentially be used
> for all climbing, but you
> better not plan on falling off.
> A twin rope is much safer, because of
> the higher capacity and the redundancy
> (only one strand may be cut).
> Using half ropes like a twin, clipping
> both strands in every carabiner
> is, of course, the safest solution
> (a pair of decent half ropes,
> tested like a twin rope will most
> likely hold over 30 falls).

Safest, unless one considers impact force:

> Using two half ropes clipped in
> together will produce forces on the
> protection higher than when using
> a single rope. Twin ropes act like a
> single rope.

Actually, no. Twin ropes as a general
rule have a higher impact force
than most single ropes. They also hold
more high factor falls.

> So in a scary, poor ice, situation
> the only thing, which may be of
> value, is to put protection at very
> close spacing.

The only thing? How about Screamers
or other load limiters? How
about self-equalizing placements
in combination with screamers?

In fact, it has been my experience that
in scary, poor ice, NOTHING will likely
hold a fall, regardless of what rope I'm using.
Don't fall. Period.

> but that unfortunately is often not possible.
> But it would help to clip both ropes in the
> last bomber protection.

True. I agree there. But how about what
I also do when I can in these situations:
Place TWO good screws at your last good ice and
good stance. ("last bomber protection")
Load limiters on each. Clip half,
twin or single rope in accordance with standard
half, twin, or single rope technique. Sure,
sometimes ya can't, but no hard-and-fast rule
applies to all situations (except DON'T FALL (TM).
It's a BIG DEAL (TM). You could DIE (TM).)

Where two bomber pieces are not possible,
but one piece is, yes, it does make sense to
clip both half strands. And don't forget
the load limiter.

> 3. How soon/often do I have to retire
> the half ropes provided I take
> falls on them (very few climbers are
> 55kg and under, I am 90kg)?

When you no longer trust them.

> If there are no sharp edges, a rope
> could most likely be used until
> the mantle starts shredding and can no
> longer be used in a belay
> device. This applies mainly to a
> single rope. The half rope is simply
> not designed to take major leader
> falls. But as mentioned before, the
> forces in the system are determined
> by the belay device. With a
> properly working dynamic belay, not
> much will happen to the rope. Do
> not belay with a static belay device
> such as a Grigri,

Yaah, like, everyone here routinely
uses the grigri for belaying on
double ropes and twin ropes. First, it
would take two grigris to belay on
either twins or halves. Second, the
grigri is not designed for ropes of that
small a diameter ANYWAYS: From the
Petzl website, Grigri technical notice--
the grigri "is for use only on single
UIAA ropes from 10mm to 11mm in diameter."

Once again, a straw-man issue.

> which should be used for top roping only.

Hmmm. I also can't say I agree that
the grigri is only for top roping.
Also from the Petzl website, grigri
technical notice: "The Grigri is
a belaying device for the leader or second
on a rope." When used intelligently, the grigri
(together with the climber) can apply a dynamic
belay in a leader fall situation. Use of
load limiters (Doesn't anyone but me use
these things??) also has a large effect
on the impact force.

> 4. Is the conclusion that one just
> should not buy or use half ropes?
> Or they are still manufactured for
> cases where falls are not dead
> vertical, in alpine terrain wit
> lots of rope drag? Or perhaps they are
> manufactured out of inertia and
> for marketing purposes?

> They are most useful in alpine
> terrain where lots of friction may
> result, if the ropes are clipped
> in all the runners. An additional
> advantage is that there is a backup
> rope of sufficient capacity,
> should a rope be cut by rock fall.
> Finally the rope offers redundancy
> in the case of sharp edges. Double
> ropes have more holding capacity
> over an edge to start with. Even
> if both ropes run over the same sharp
> edge, it is less likely both get
> cut because one will get loaded more
> than the other. In a retreat,
> being able to rappel the full length of
> the rope is invaluable.
>
> The other option is to climb
> with twin ropes. Extra edge strength
> (remember twelve UIAA falls minimum),
> redundancy, lighter ropes, in a
> severe case the option of clipping
> in alternately,

Whoa. Clipping TWIN ropes alternately?
wonderful advice. Just wonderful. No, thanks.

> rappel convenience.
>
> I personally have not owned a single
> rope for at least 25 years.

I personally own uh... eight different
lead ropes of the single variety, ranging from
70m x 11mm to 50m x 9.2mm. One set of twins (ice floss)
and sometimes we also use my partner's half-ropes.

> I used to climb with two half ropes
> and clipped them together when it
> was suitable.
>
> Now I climb with twin ropes. I use
> these ropes in any terrain.

Personally I would not follow some of this
fella's advice if you paid me.

1. My standard on long trad, walls, and
backcountry is still single rope.
When taking a pack, (or haul bag) a
second lighter rap line serves
as a haul line as well. In most
1-day, 2-climber situations it is
not possible to haul with
twins or doubles, as they pass
through protection, thus
one UIAA single plus a light haul/rap rope is
the lightest solution for many specific
situations.

2. On big walls with a team of three, the fuster-
cluck from using twins or half-ropes can be
mind-boggling.

3. When fixing ropes, on vertical terrain
in the backcountry, the thinnest I
will accept is a half-rope (aka double).
I consider a single strand of twin
to be too thin, due to the
possibility of cutting over an edge
while sawing up and down as I jug,
similar to what happened to Harlin
on the FWA of the Eiger NF (7mm jug
rope cut).

Conclusion:
I say different gear for different
situations. Twins, doubles, and
singles all have their place. Twins
may be best for everything *you* do. Or
halfs (doubles.) Or single ropes.
If your climbing ranges from roofs
and wandering edgy routes to steep
featureless ice to big walls to fixing
ropes on new remote routes
in the backcountry, to alpine, to
sport, to bouldering, to gym routes,
you may find that a quiver of different
types and lengths of ropes is
best, and to select for each climb
based on your anticipated needs.

Short on cash? then get the rope
most suited to the kind of climbing
you typically enjoy.

Just my two ascents' worth.

Brutus

brewtie,

is it okay if i get bumperstickers of the above made? because that rocks. royalties to be worked...

best,
mkg
__________________________
make way for gumby!

Screamers good. Ice screamers bad. Be careful when equalizing to use only one or make sure the screamers are in series, not in parallel.

I'm on my second set of doubles. The first set was PMI Verglas 8.1s. They croaked when the green one took a core shot in December. I replaced them with Mammut Phoenix 8.0s. The Mammut ropes have a double pic sheath which really cuts down on the tangling issues I had with the single-pic PMIs.

Anyway, I like the flexibility of clipping one or both ropes. If the pitch doesn't wander and the screw is bomber, then I clip both. The ropes are stretchy, so I know that a fall from 20 feet above a screw onto one strand is probably a 50-footer, but that is still better than a full-force grounder because the impact force blew out the screw. And I expect to retire the ropes if they sustain one significant leader fall. It just goes with the territory.

I use a 37m Ice Floss for glacier walking. It handles three fine and four in a pinch. More than that on one rope is a pain anyway.

Don't do what I do, but I've used the Ice Floss for moderate rock, where we are simul-climbing the whole time, and I used a single PMI Verglas on the Jefferson Park Glacier route. It is a calculated risk.

I like what they say in the "West Coast Ice" book: Regardless of what anyone says about clean ascents and good form, the worst possible style is to fall.

Amen, especially on ice.

Mr. Wyde, how was your trip to The Great White North, eh?

-CascadeClimber

<snip>
Screamers good. Ice screamers bad.
<unsnip>

Okay, what have I missed? Why negative bias towards ice screamers? Short and sweet, I'll do my research on r.c as well. I'll start with force data and work from there (activation, load mitigation, that sort of thing), but I assume there's some other factors involved. Not the colors.

Being relatively new to WI ice leads (relatively=1-1/2, I sketched out this weekend on a nasty WI4 hooking problem about 40' up and took the smart alternative) I'm interested. Working on funding for screamers... Until then, just lots and lots of pro close together combined with in-my-ability leads should help me out.

All righty. Looks like tele, maybe a pitch at Shroud this weekend.

tradkelly
http://www.geocities.com/tradkelly

I have four of them that I used a lot last season. Unless I clipped the two biners together, which made for an extra step when placing a screw, they hung too low off my harness and I repeatedly caught my crampon points on them. Nothing like going for a highstep twenty feet above your last screw and getting your foot caught on your ass.

So I ditched them this season and switched over the the regular Yates Screamers, which are long enough to help minimize drag, but short enough to stay out of the way.

YMMV

-CascadeClimber

Brutus

>However, in a half-rope setup,
>the higher the fall factor,
>the more the second rope shares in the load,
>regardless of the length of runout between
>pieces. It is a directly-porportional
>relationship.

Can you explain this further? How does this work when the fall is caught by only one rope? What am I not understanding?

>The only thing? How about Screamers
>or other load limiters? How
>about self-equalizing placements
>in combination with screamers?

Absolutely! Screamers are a must for ice. Personnally, I place more pro (when possible) and use screamers when the fall factor is the highest and decking is most likely if a piece fails, right off the ground/ belay. Fall factor plays a huge role in the loading of protection. I run it out farther when higher off the ground. Also in ice, the lower impact force afforded by half ropes is beneficial as well by causing less impact on a screw in the event of a fall.

I have heard that clipping both ropes of a half rope system into one biner can cause improper loading on that biner due to the thickness of the ropes. Can anyone comment on that? Perhaps its less of an issue with todays thinner ropes.

I'll try, although my understanding of
the subject is far from expert, and mostly
gleaned from discussions with Ken Cline on
Rec.climbing...

(bear in mind also that percent elongation for a dynamic
rope represents elongation under a static body weight,
not the behavior of the rope in a shock-absorbing
situation.)

First let's look at the worst cases
for both ropes catching the fall, and for one
rope catching the fall in a half-rope system.

I'm going to eliminate the wierd scenarios from
the discussion, such as the soloists' rope and
carabiner fatality on ZM on the Captain during a 2+
factor fall from the rope jammed in a crack, etc.

Let's take a factor two fall (supposedly worst-
normal-case except in via ferratta setups):

Climber climbs above belay 20 feet, no pro in,
falls past belay, fall length 40 feet + stretch,
20 feet of rope out:

the fall WILL be caught equally by both ropes:
Used appropriately and traditionally, a factor
2 fall onto just one of a double rope pair is
just not possible.

With me so far?

Okay. Now: Factor 1 fall: Climber climbs
10 feet off the belay, clips just one rope,
climbs another 10 feet off the piece, and falls.

Fall length is 20 feet plus rope stretch, with
20 feet of rope out. Fall is held by only one
rope. *But this is only a factor one fall.*

Factor 1.2 or 1.3 fall is probably somewhere near
the worst case scenario that a single rope of
a half rope pair will need to hold, at a mindless
guess, depending on dynamic elongation characteristics
of the individual ropes and assuming no sharp edges:

Leader places a piece 5 feet off belay,
clips one rope, continues 10 feet and falls off...

15 feet of rope out, 20 foot fall (plus stretch)
Putting the leader about 5 feet below the belay.
Fall factor 1.333. Lets pretend that the first rope
fails at this point. Lets also pretend that the
failure has dissipated most of the force of the fall.
The remaining rope (15 feet out, directly onto
the belay device since only the first rope was
clipped) sees an additional 10 feet of fall
created by the failure of the first rope, putting
the leader 15 feet below the belay. Fall factor
for the second rope is at most 0.666

ALL THIS assumes no slippage of the thin first rope
through the belay device (an unlikely scenario
but we're looking at worst case.)

Now let's look at somewheres in between these two
worst cases:

Leader places a piece just above the belay, say
1 foot, climbs an additional 10 feet, and falls off.

11 feet of rope out, 20 foot fall... Factor 1.8 fall.
A big fall, to be sure. But rope stretch in the first
rope (not to mention slippage) allows the second rope
to come into play in absorbing the fall. Even were the
first rope to fail completely (unlikely except by
cutting) only a short, additional, low-factor fall
would result with little additional force needing
to be absorbed by the second rope.

OK, so much for theory.

Reality is that the additional distances fallen in many
cases vastly increase our likelyhood of injury or death,
regardless of what rope absorbs what force. Hence the
advice to clip both ropes into bomber pieces, and both
into pieces before long runouts.

Reality also is that rope failure is usually due to
either rockfall or cutting over an edge, whereinn
the redundancy of twins and doubles are a plus.

Reality also is that most climbing fatalities
are due not to equipment failure but operator error
made in distracting situations.

Reality also is that in ice climbing we got a lot of real
sharp objects attached, capable of damaging the rope,
ourselves, our partners, or all three.

Hence the advice: Don't fall.

What it all boils down to,
then, is that the double
ropes have the advantage
of redundancy, not needing to
carry an additional rap rope
in some situations, the
flexibility of either reducing
rope drag and impact force by
alternate clipping, or maximum
holding power by clipping in
twin configuration.

Singles and twins have their own advantages.

>Screamers are a must for ice. Personnally, I
>place more pro (when possible) and use screamers when the
>fall factor is the highest and decking is most likely if a
>piece fails, right off the ground/ belay. Fall factor plays
>a huge role in the loading of protection.

On ice these days, nearly every screw gets a screamer
on my leads. Sometimes the belay directional also.

>I run it out
>farther when higher off the ground. Also in ice, the lower
>impact force afforded by half ropes is beneficial as well by
>causing less impact on a screw in the event of a fall.

True. Personally I like twins because with half-ropes I
a) have trouble remembering which one I clipped
b) have trouble keeping two separate ropes from behind my legs
c) get comfoozled and sometimes "trap" one rope when I clip
the other, ending up with tangles and twists.

>I have heard that clipping both ropes of a half rope system
>into one biner can cause improper loading on that biner due
>to the thickness of the ropes. Can anyone comment on that?
>Perhaps its less of an issue with todays thinner ropes.

Haven't heard that, but many of todays half-ropes
are as thin as the twin ropes of the past.

I have heard that due to the different paths the two ropes
take and thus different lengths and stretch in a fall,
that they should be each run through separate carabiners
so one will not saw through the other.

Brutus

Excellent post. Thanks, Zeno.

kelly
http://www.geocities.com/tradkelly