Gate Flutter and Gate Shutter Explained

There are two types of scenarios that will unintentionally cause a carabiner’s gate to open.

1. Gate Flutter – when the movement of the rope through the carabiner creates a harmonic vibration in the carabiner causing the gate to slightly open and close (“fluttering”). This could be caused by a really big fall where the rope enlists a lot of weight on the carabiner.

Gate flutter happens more dramatically on solid gate carabiners versus wire gate carabiners and is why many folks have recommended using wire gate carabiners on the rope-end of a quickdraw.

2. Gate Shutter – When the gate opens (“shutters”) due to the spine of the carabiner hitting against some debris (rock, other hardware, etc). This problem is exacerbated when it opens the carabiner gate at the same time the full force of the fall is absorbed as you are now in an “open gate” position, certified to a much lower strength rating.

You can see an example of gate shutter in action on this non-scientific YouTube Video:

We made this blog post to accompany other posts that mentioned gate flutter such as, Ensure your carabiner is strong enough to climb on.