The Munter hitch belays with one screw-gate carabiner and friction. Where it makes sense, where it does not and why you learn it only in a course with a coach.
The Munter hitch, HMS for short in German, is the simplest way to use a rope as a brake: the rope runs in turns around a screw-gate carabiner, and friction replaces the belay device. The honest answer to "Do I even still need it?": in the gym no, in the mountains sometimes yes, and in an emergency it is the hitch that works with a single carabiner.
The advantage is radically simple: you need only one screw-gate carabiner [1]. Today the hitch is mostly used in alpine terrain on easy multi-pitch routes, especially from the belay stance. There you belay leader and second without being directly part of the chain, and you are not pulled uncontrolled towards the wall in a leader fall [1].
The price: the Munter hitch forgives no belaying mistakes and twists the rope [1]. For climbing gyms and crags the German Alpine Club therefore recommends assisted-braking tubes or semi-automatic devices, because if the brake strand is lost they massively reduce the chance of a ground fall [1].
The Munter hitch is the reserve parachute among belay techniques: you want to know it, but not use it every day.
Entry criteria (practice standard):
Device and hitch brake by the same principle: friction. As on a bicycle: without brake pads you would have to put your feet on the ground, with a brake a light squeeze on the lever is enough [1]. With the Munter hitch the friction arises in the carabiner, and your brake hand remains the last part of the chain.
Milestone: You explain to your coach in your own words where the friction arises and why the brake hand must never let go.
You practise the set-up in the course without load and with a coach. For changing over at the stance the DAV describes: lay the lead rope "in line", that is as it is meant to run upwards, in the HMS carabiner, so that it runs without interference and over the "healthy leg" of the carabiner [2].
Milestone: You set up the hitch correctly three times in a row without your coach correcting.
When taking in rope even experienced belayers sometimes fall into the dangerous "tweezer grip", where the brake strand is held only with two fingers [2]. That is exactly what you train the brake-hand position against until it sits automatically.
Milestone: Your coach sees you take in ten metres of rope without the brake hand ever leaving the rope.
In the course you first hold a fall with weight on a back-up belay by a coach or third partner. That way you feel how the pull comes through the brake hand without anything being able to happen.
Milestone: You have held several falls in the course and then re-set up the rope cleanly.
One of the most important skills is deciding against the Munter hitch. With two seconds it cannot be used sensibly, here the plate is standard [2]. And in half-rope use with only one loaded strand, the unloaded second strand can be badly damaged by the rope running past, up to being severed [3].
Milestone: You name three situations in which you do not choose the Munter hitch.
Belaying is the role in which mistakes cost most. In an Austrian analysis of climbing rescues, 138 falls were accompanied by a belaying error. The authors advise high vigilance when belaying [5]. The Munter hitch is more error-sensitive than modern devices: if you let go of the brake strand, nothing holds. That is why the DAV recommends semi-automatic devices as the primary device for sport climbing [6].
Practise the hitch once deliberately on the ground with a weight, for example a full rucksack on a back-up belay. You learn in peace how the rope runs and how much force the brake hand needs. That is course practice, not a study finding, but it lets you understand the hitch before an emergency demands it.
Mainly in alpine terrain on easy multi-pitch routes, especially from the stance, and as a solution when only one screw-gate carabiner is available [1]. In gym and crag it is not the recommended standard device.
Not automatically. With correct handling the braking effect is high; a DAV expert article even rates the hitch above any tube in braking value with double or twin ropes [3]. At the same time it forgives no belaying mistakes and twists the rope [1].
The hitch lays the rope in turns around the carabiner and creates kinks [1]. That is part of the technique. If you lay the rope "in line" it stays easier to handle [2].
No. Setting it up looks simple, but a mistake stays unnoticed until the first fall comes. Learn the hitch in a course with a coach and a back-up belay.
With two seconds at once when the plate fits better [2], and with half ropes when only one strand is loaded [3]. When in doubt you choose the device you got to know in the course.
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