While doing a 2-way jump with a friend, this skydiver's chest strap came undone in freefall at 5,500 feet! With only a few seconds before they had to deploy, they realized they probably didn't have enough time to re-route the chest strap, so they just held onto it while they deployed.
We don't have video from prior to the jump, so we don't know what happened in the plane or on the ground. On top of that, the description that came with the video didn't really elaborate on what might have caused this.
Consequently, all we can do is make logical assumptions about what happened. Our particularly sensitive senses of deductive reasoning leave us thinking that this jumper's chest strap was never routed properly to begin with and it slowly came undone in freefall.
If this chest strap was misrouted, then it should have been noticed by either the jumper or their friends! There's no reason that a jumper should ever get onto a plane without having realized that this scenario is about to occur. They should have noticed during their gear checks. Their buddies should have noticed during buddy checks. Their fellow jumpers should have noticed because we should ALL be looking at one another's chest straps and handles in the plane... to make sure this EXACT scenario doesn't happen.