UKC

I was on a sport climb the other day, took a whip and managed to bend the gate out on the quickdraw and it then came unclipped. I was fine and just fell down to the next draw. Any ideas how this could have happen? See pictures

The dent in the gate suggests it took the load on its side with the gate open, which would push it sideways around the nose. What sort of bolt was it?

I'm no expert (at anything) but in the first pic there's scarring on the side of the nose of the biner. It looks to me like the biner could have got pulled at an angle sideways hard enough to let the gate open and pop through the gap maybe? 

That's a complete guess though so feel free to ignore/laugh/deride or all three.

edit: snap - Not just me thinking that then

It was a petzl bolt hanger but it was oriented fully horizontal not the 45° they usually are. I think because I clipped over the top of the bolt the gate was the rock side and caused it to torque sideways in the bolt?

I've got mates who have done this. Did the bolt-end krab come completely off the bolt or did the tape slide off open gate of the bolt-end krab leaving the top krab on the top bolt? I know of cases of each. From the position of the gate I suspect it's more likely you fell when somehow the sling was on the gate of the krab, that opened it and wrenched the gate open, but in that case I would expect the bolt end krab would have stayed on the bolt or fallen to the floor, while the tape and rope-end krab would have still been on the rope?

If the krab was still on the tape, so therefore attached to the rope, its more likely somehow the krab caught on the bolt and got levered open, so just came of the bolt. It's less likely to happen with plaingate keylock krabs but I'm sure it still can!

You're unlucky, but statistically I suspect it's not that uncommon as taking falls is such a normal part of sport climbing, 

That sounds likely. Hangers that have turned are very much prone to twisting krabs in ways that can cause failure.

The best advice I can give, when faced with a hanger that's sticking out sideways, is to clip the krab into it such that the gate faces away from the bolt, regardless of what effect this may have on the orientation of the krab at the other end of the quickdraw, since the primary risk will now have become one of the top krab failing rather than the still hugely unlikely risk of the bottom krab coming unclipped.

This has happened to me before. In my case it was a route with quite old bolts with homemade hangers. I think, in my case, the crab twisted and got wedged horizontally in the bolt and the tape pulled onto the gate. I was also fine, and was caught by the next bolt, but it did make me wary.

At the time I emailed both the BMC and the manufacturer with pictures, but they both pretty much said that it happens and you should build redundancy into the system. 

What style bolt?

It could have simply been overloaded in the off-axis direction by a hard fall or it could have been hung up so some additional leverage was applied and or the gate opened by the bolt/hanger. The witness mark hints at the latter but without seeing it in the bolt I'd be guessing.

Worrying!

jk

Weird crossloading comes into the picture I'd assume.. if the bolt is rotated near the gate, gate flutter opens the gate, krab opens enough to let the nose out and then gate snaps back to it's final position.  But the other suggestions are good and maybe more likely

Not really the same thing but I had a very odd occurance at an indoor wall once.

I was dogging up the main overhang and I was resting on clip 4 or 5. I noticed that my rope was no longer running through the quickdraw below me but I had definitely clipped it. I know this because I also hung off that quickdraw. How the rope unclipped itself from the rope-end biner I'll never know. 

Hi John,  my preference is to always clip the quick draw such that the rope end has the gate facing away from the direction of the climb / me. If I had a concern over the orientation of the gate at the bolt end I would just flip the krab so it hangs upside down in the bolt,  but now with the gate on the favoured side. Do you see any issue with that?

Cheers

No issue at all. That's also a good strategy.

Could it have been accidentally half clipped to the bolt hanger in some way that the hanger remained caught in the nose, holding the gate part open and the fall was taken by an open carabiner. With all the force on the nose, bending the basket/nose open away from the spine the gate could have popped open past the nose like that and unclipped from the hanger

We'll probably never know, but it's a *theory* that would explain it all?