Ascender (climbing)

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A pair of left and right handed ascenders (the left rigged to a rope) Petzl Ascenders (On Rope).jpg
A pair of left and right handed ascenders (the left rigged to a rope)

An ascender is a device (usually mechanical) used for directly ascending a rope, or for facilitating protection with a fixed rope when climbing on very steep mountain terrain. A form introduced in the 1950s became so popular it begat the term "Jumar" for the device, and the verb "to jumar" to describe its use in ascending.


Ascenders can also be used as a braking component within a rope hauling system, often used in rescue situations.


Ascenders in use on a single rope on a steep mountain slope, offering the two climbers both security plus an additional aid to their upward ascent. Note that they are not roped together, but are climbing independently of one another. Zumarovani.JPG
Ascenders in use on a single rope on a steep mountain slope, offering the two climbers both security plus an additional aid to their upward ascent. Note that they are not roped together, but are climbing independently of one another.

Ascenders are usually used in pairs on a single rope, and offer similar functionality to friction knots, but are faster, safer and easier to use, [2] albeit still with consequences in weight and in security (as ascenders can, even with a locking carabiner, come off the rope, and fail by shredding the rope at high loads, rather than slipping and fusing as with friction knots). A mechanical ascender employs a cam which allows the device to slide freely in the intended direction of movement, but provide a firm grip on the rope when pulled in the opposite direction. To prevent an ascender from accidentally coming off the rope, a locking mechanism or trigger is deployed. The ascender is first attached to the climber's harness by a piece of webbing or sling, and then is clipped onto the rope and locked on.

Ascenders are usually used in pairs, so that one is free to be slid up the rope whilst the other bears the weight of the climber. The ascender which has just been slid upwards is then made to take the climber's load, locking the climber to the rope, and freeing the other one so it can then be slid upwards too. The process is then repeated to ascend the rope. [2]

For climbing on with a fixed rope attached for security (for example, to snow anchors on a steep slope) only one ascender is used, keeping the other hand free for holding an ice axe.

Ascenders are not used on free climbing routes, where a climber uses only their hands and feet on the features of the rock without artificial aids to gaining elevation (though mechanical aids purely for protection are acceptable). Instead, they are used in aid climbing, where aids to ascending and weighting "protection" to assist elevation gain are allowed. [3]

The climbing verb "to jumar" means to use an ascender (generically) to "climb" a rope, regardless whether it is done in sport climbing, caving, in occupations that require working from (or being protected by) ropes, or a rescue. A form of sport climbing exists where the "second" belays the leader, then follows "up the rope" without climbing the rock or ice using an ascender. Terms applying to such a second's ascent include "jumaring", "ascending", and "jugging". [4]


Historic Jumar rope ascender (ca 1975) Jumar rope ascender.png
Historic Jumar rope ascender (ca 1975)

The first mechanical rope ascending devices were created by Henri Brenot, and were used in France both for mountaineering and caving as early as 1934. [5]

A popular example of the ascender is the jumar, named for its inventors Adolph Jüsi and Walter Marti and the Swiss firm Jümar Pangit they created to manufacture it, beginning in 1958. Jusi was studying eagles for the Swiss Government, and desired an ascender (rather than relying on the traditional technique of prusiking using friction knots; Marti developed one for him. [6]

French caver Fernand Petzl developed a mechanical rope ascender in 1968, and his company Petzl continues to produce both handled and handleless models that are popular with mountaineers and cavers today.

In his 1978 memoir Life Is Meeting, John Hunt, leader of the 1953 British Mount Everest expedition, credits the jumar with enabling climbers "to climb at alpine standards even at high altitudes". [7]

Other countries, notably the United States, have also produced rope ascenders. Other names for different specialized styles of ascenders include 'ropeman' and 'tibloc'. [3]

Versus friction knots

Using ascenders in to jumar up a fixed rope. Jumaring.webp
Using ascenders in to jumar up a fixed rope.

Used correctly, ascenders are safe, dependable, and require less effort and dexterity of a climber than the traditional method of ascending and descending ropes using friction knots and short lengths of cordage (or nylon slings) known as prusiks.

The principal disadvantages of ascenders relative to the "prusiks" [8] [2] :46–48 are weight, complexity, and possibility of failure due to coming off a rope or mechanical issue with the device.

Certain specialty forms of ascender - but not all - are capable of taking a dynamic load (as in preventing a fall), whereas the friction knot/Prusik combination may the synthetic sheath of the climbing rope or sling and fuse under such extreme forces. [9]

Related Research Articles

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<span class="mw-page-title-main">Tree climbing</span> Ascending and moving around in the crown of trees

Tree climbing is a recreational or functional activity consisting of ascending and moving around in the crowns of trees.

<span class="mw-page-title-main">Glossary of climbing terms</span> For rock climbing and mountaineering

Glossary of climbing terms relates to rock climbing, mountaineering, and to ice climbing.

<span class="mw-page-title-main">Rock-climbing equipment</span> List of manmade gear

Rock-climbing equipment varies with the type of climbing undertaken. Bouldering needs the least equipment outside of shoes and chalk and optional crash pads. Sport climbing adds ropes, harnesses, belay devices, and quickdraws to clip into pre-drilled bolts. Traditional climbing adds the need for carrying a "rack" of temporary passive and active protection devices. Multi-pitch climbing adds devices to assist in ascending and descending fixed ropes. And finally aid climbing uses unique equipment.

<span class="mw-page-title-main">Abseiling</span> Rope-controlled descent

Abseiling, also known as rappelling, is the controlled descent of a steep slope, such as a rock face, by moving down a rope. When abseiling, the person descending controls their own movement down the rope, in contrast to lowering off, in which the rope attached to the person descending is paid out by their belayer.

<span class="mw-page-title-main">Crevasse rescue</span> Retrieving a climber from a crevasse

Crevasse rescue is the process of retrieving a climber from a crevasse in a glacier. As a result of the frequency with which climbers break through the snow over a crevasse and fall in, crevasse rescue technique is a standard part of climbing education.

<span class="mw-page-title-main">Solo climbing</span> Style of climbing performed alone

Solo climbing, or soloing, is a style of climbing in which the climber climbs a route alone, without the assistance of a belayer. By its very nature, it presents a higher degree of risk to the climber, and in some cases, is considered extremely high risk. Note that the use of the term "solo climbing" is generally separate from the action of bouldering, which is itself a form of solo climbing, but with less serious consequences in the case of a fall. The most dangerous form of solo climbing is free solo climbing, which means both climbing alone and without any form of climbing protection.

Self-locking devices are devices intended to arrest the fall of solo climbers who climb without partners. This device is used for rope solo climbing, for "ground-up climbing", and for "top rope solo climbing". To date, several types of self-locking devices have evolved.

<span class="mw-page-title-main">Munter hitch</span> Adjustable knot used control friction in a belay system

The Munter hitch, also known as the Italian hitch, mezzo barcaiolo or the crossing hitch, is a simple adjustable knot, commonly used by climbers, cavers, and rescuers to control friction in a life-lining or belay system. To climbers, this hitch is also known as HMS, the abbreviation for the German term Halbmastwurfsicherung, meaning half clove hitch belay. This technique can be used with a special "pear-shaped" HMS locking carabiner, or any locking carabiner wide enough to take two turns of the rope.

<span class="mw-page-title-main">Bachmann knot</span> Type of knot

The Bachmann hitch is a friction hitch, named after the Austrian alpinist Franz Bachmann. It is useful when the friction hitch needs to be reset quickly or often or made to be self-tending as in crevasse and self-rescue.

<span class="mw-page-title-main">Petzl</span> French consumer goods company

Petzl is a French manufacturer of climbing gear, caving gear, work-at-height equipment, and headlamps based in Crolles, France. The company was created by the cave explorer Fernand Petzl in the mid-1970s. Their three specialties are:

<span class="mw-page-title-main">Prusik knot</span> Type of knot

A Prusik is a friction hitch or knot used to attach a loop of cord around a rope, applied in climbing, canyoneering, mountaineering, caving, rope rescue, ziplining, and by arborists. The term Prusik is a name for both the loops of cord used to tie the hitch and the hitch itself, and the verb is "to prusik" or "prusiking". More casually, the term is used for any friction hitch or device that can grab a rope. Due to the pronunciation, the word is often misspelled Prussik, Prussick, or Prussic.

<span class="mw-page-title-main">Sling (climbing)</span> Item of climbing equipment

A sling or runner is an item of climbing equipment consisting of a tied or sewn loop of webbing. These can be wrapped around sections of rock, hitched to other pieces of equipment, or tied directly to a tensioned line using a Prusik style knot. They may be used as anchors, to extend an anchor to reduce rope drag, in anchor equalization, or to climb a rope.

<span class="mw-page-title-main">Single-rope technique</span>

Single-rope technique (SRT) is a set of methods used to descend and ascend on the same single rope. Single-rope technique is used in caving, potholing, rock climbing, canyoning, roped access for building maintenance and by arborists for tree climbing, although to avoid confusion in the tree climbing community, many have taken to calling it "stationary" rope technique.

<span class="mw-page-title-main">Autoblock</span> Rope device used in climbing and caving

An autoblock is a rope device used in climbing and caving for both rappelling (downward) and ascending (upward).

<span class="mw-page-title-main">Pit cave</span> Cave with significant vertical passages

A pit cave, shaft cave or vertical cave—or often simply called a pit and pothole or pot ; jama in Slavic languages scientific and colloquial vocabulary —is a type of cave which contains one or more significant vertical shafts rather than being predominantly a conventional horizontal cave passage. Pits typically form in limestone as a result of long-term erosion by water. They can be open to the surface or found deep within horizontal caves. Among cavers, a pit is a vertical drop of any depth that cannot be negotiated safely without the use of ropes or ladders.

<span class="mw-page-title-main">Grigri</span> Assisted braking belay device

A Grigri is an assisted braking belay device manufactured by Petzl designed to help secure rock-climbing, rappelling, and rope-acrobatic activities. Its main characteristic is a clutch that assists in braking under a shock load. The success of this device has led to grigri becoming a common name for devices of this type. In 2011 a new version, the Grigri 2, was released to replace the original 1991 model. Petzl released the Grigri+ in 2017, adding safety features to the original design, however this added weight and many climbers felt the new safety features were more of a hindrance than a help. 2019 saw the release of an updated version of the device, simply called the Grigri. It is named for the African amulet gris-gris, believed to protect the wearer from evil.

<span class="mw-page-title-main">Belay device</span> Mechanical piece of climbing equipment

A belay device is a mechanical piece of climbing equipment used to control a rope during belaying. It is designed to improve belay safety for the climber by allowing the belayer to manage their duties with minimal physical effort. With the right belay device, a small, weak climber can easily arrest the fall of a much heavier partner. Belay devices act as a friction brake, so that when a climber falls with any slack in the rope, the fall is brought to a stop.

<span class="mw-page-title-main">Z-drag</span> Method of increasing the pull on a rope

A Z-Drag or Z-Rig is an arrangement of lines and pulleys, effectively forming a block and tackle, that is commonly used in rescue situations. The basic arrangement results in pulling the hauling end 3 times the distance the load is moved, providing a theoretical mechanical advantage of three to one. In actual practice the advantage will be reduced by friction in the pulleys or carabiners. The advantage will also be reduced if the pull on the hauling end is not parallel to the direction the load moves in. The name comes from the fact that the arrangement of lines is roughly Z-shaped. Besides the mechanical advantage to pulling, it also uses only part of the total length of the rope for the block and tackle arrangement.

<span class="mw-page-title-main">Dülfersitz</span> A classical abseiling technique

The Dülfersitz, also known as body rappel is a classical, or non-mechanical abseiling technique, used in rock climbing and mountaineering. It is not used frequently any more, since the introduction of belay devices. In the Dülfersitz, the rope is wound around the body, and the speed of descent is controlled using the friction of the rope against the body.


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  3. 1 2 Houston, Mark; Cosley, Kathy (2004). Alpine climbing : techniques to take you higher. Seattle, WA: Mountaineers Books. p. 86. ISBN   0898867495. OCLC   55672068.
  4. Cox, Steven M.; Kris Fulsaas, eds. (September 2003). Mountaineering: The Freedom of the Hills (7 ed.). Seattle: The Mountaineers. ISBN   0-89886-828-9.
  5. Chevalier, Pierre Subterranean Climbers Faber & Faber, London, 1951. ISBN   0-914264-14-1
  6. This page (archived) gives an overview on the older jumar models. A current model is still in production.
  7. Hunt, John (1978). Life Is Meeting. London: Hodder and Stoughton. p. 122. ISBN   0340229632.
  8. "Self Rescue for Climbers 4 - Prusiking Up a Rope" . Retrieved 2018-03-30.
  9. March, Bill (1983). Modern Rope Techniques in Mountaineering . Cicerone Press. pp.  38. ISBN   0902363409.