In 1961 Toni Hiebeler, Toni Kinshofer, Anderl Mannhardt, and Walter Almberger completed the first winter ascent of the North Face of the Eiger. They spent 6 cold March days trusting their lives to their skill, thier gear and to each other.
After this historic ascent Hiebeler, who was a writer and gear designer, developed the “Hiebler Steigklemme (ascender)” in partnership with Salewa Equipment Company. I can only guess that his experiences on frozen faces in the Alps led him to design something that worked better on dangerous icy ropes than methods available at the time.
The Hiebler ascender was introduced in the mid 1960’s and produced through three distinct versions into the 1970’s. The original (version A) pictured above was a simple rope clamp consisting of a body which held the rope and a spring loaded camming arm. When the rope was inserted it was supposed to be held in place by the spring action of the cam and the design of the rope tunnel. As a climber applied their weight to the arm of the unit it would pinch and hold the rope allowing for upward movement. They were designed to be used in pairs for vertical rope work but could be used singly for fixed ropes on lower angle terrain.
The design was never very successful. I have found references as early as 1967 warning of the tendency for these to twist off the rope under “normal” use. Lateral loading was the major problem. Heiblers could twist off under some circumstances. The later units (versions B and C) tried to address the issues by incorporating a small clip which was supposed to keep the rope in place. These fixes where never very effective.
A simple method for backing up the Hiebler with a Prusik knot did add an extra safety margin but diminished the speed and convenience of the ascender and made knot passing more difficult.
It was important to size the Prusik knot so it would not interfere with the operation of the camming arm. If it was too long the Prusik tail could get caught in the mechanism; too short and the cam and the knot might fail to fully engage.
Many early ascenders had growing pains similar to the Hiebler ascenders. Early Jumars could come off the rope easily and some climbers felt that the weak cast aluminum body needed to be backed up by rigging slings through the upper attachment points as well as through the bottom of the handle. These fixes solved most of the problems and the versatility of the design allowed for confidence inspiring design improvements through the years.
Sadly, the very simplicity that made the Hieblers so interesting also left the design with no way to improve safety without a radical change in approach. Altering the depth of the rope tunnel and the size of the cam would have seated the rope deeper in the unit but would have increased the already extreme bend in the rope created when the unit was weighted. Adding a handle would have essentially made it a Jumar and probably weakened its main claim to fame, holding power on icy ropes. Adding the clips, as in the later versions, didn’t increase the safety enough (the clips bent easily) and thus didn’t inspire confidence or positively affect reliability. Some climbers of the day came to refer to Hieblers as “death clamps” but it is unclear whether any fatal accidents can be attributed solely to the ascenders.
On the left a Heibler (version A) with no safety clip followed by later model (version B) showing the position of the clip.
A lightly weighted Heibler showing the bend put in the rope during normal operation.
Toni Hiebeler’s design was elegant but flawed. The ultimate problem being that the action required to advance the ascender was also the action required to disengage the ascender from the system. Moving the piece a little too aggressively produced unintended results leading to dangerous consequences for the climber.
Salewa Heibler Ascenders were an interesting side road in fixed rope climbing technology. They might, as one climber said, have been like “staring death in the eye and not liking what you see…” but they were probably a necessary step to prove the concepts and develop the tools we use today. Although they seemed to be unsuited for most vertical single rope techniques developed around the Yosemite method (being virtually impossible to incorporate into an efficient hauling system[iii]) they did have a few uses in alpine and expedition climbing as well as fans in the caving world. Doug Scott, in his 174 book “Big Wall Climbing” states “…they (are) very effective on icy ropes and (are) often carried by alpine climbers”. While the December 1968 edition on the National Speleological Society News mentions their superior holding power on ropes with damaged sheaths.
By the late 1970’s climbers were warning against the use of Heibler ascenders and recommending safer more efficient designs[iv]. Still, these unique tools were interesting for their simplicity and form, but were terrifying in their function. Toni Heibelers design went out of production in the mid to late 1970’s.
A note on the name: Toni Hiebeler spelled his name “Hiebeler” and the name on the units dropped the middle “e”. I have heard several explanations suggested for this:
· “Hiebler is the English spelling of Hiebeler” – This seems unlikely.
· “Purposeful renaming of the product by Salewa” – again, why? Unless it was to slightly distance the company from any controversy surrounding his winter ascent of the Eiger Nordwand[i].
· “Oops!” – Maybe a casting mistake? Why wouldn’t it have been corrected?
My inquiries to Salewa have not provided any answers to the interesting mystery of the name and have even offered up a new puzzle:
· The exact date of introduction seems to be in question. Prototypes and early production models may have been circulated as early as 1961/1962 but Salewa representatives don’t have records of manufacturing that early. Patent inquiries have come back with little additional information[ii].
[i] This first winter ascent of the Eiger North Face (nordwand) was completed in two sections. The team climbed up to the train tunnel door and exited the face to escape a coming storm. They left their gear and descended to town for 5 days returning later to retrieve their gear and continue to the summit taking 6 more days to complete their ascent. Most climbers of the day recognized the difficulty of the climb but as with many climbs in the public eye, there was some media unpleasantness.
[ii] Patent inquiries were made though US and European databases as well as available online resources.
[iii] The traditional Yosemite hauling system was roughly 1:1 ratio and used 2 ascenders and a pulley. One ascender was inverted on the haul bag side of the rope in order to capture the slack as the climber pulled up the haul bag. Heibler bent the rope when loaded and were horribly inefficient (or impossible!) in this roll.
[iv] Many recognized the issues almost immediately upon their release thus the redesign and addition of the safety clip. The following appeared in NSS newsletter dated March 1969 in response to a previously favorable review: