After an uneventful wingsuit jump, this skydiver deployed their main while appearing to be in a slightly uneven body position. The main opened with some minor line twists, but the jumper was unable to get out of them and made the decision to cutaway and deploy his reserve — but the reserve failed to fully deploy! The jumper was on his back with the reserve pilot chute in front of him, so he attempted to pull the reserve out and as he did so, he also rolled to his belly. The reserve deployed and the jumper landed safely. (We don't know where they landed, but given that it was a wingsuiter, we assume it wasn't at the dropzone.)
(We're going to skip over the line twists because, obviously, had the jumper not had line twists in the first place, this whole incident would have been prevented.) While we expect a reserve to deploy regardless of body position, here it appears that the way the jumper was positioned on their back as they pulled their reserve handle prevented the reserve pilot chute from creating enough pull force to remove the reserve pin. Consequently, the pull force is largely — probably exclusively — being exerted on his body, rather than on the pin which needs to be extracted in order to deploy the reserve.
Regarding how the failed reserve deployment could have been prevented — again, outside of not having line twists! — as is clearly visible in the video, the reserve pilot chute goes over the jumper's shoulder. As we see in the video, the second he rolled over, the reserve deployed. It seems like such a simple thing but because we all expect our reserve to be infallible, we may not think about this. This video is a great example of why not just trusting your equipment, but knowing how it works, is important in our sport.
After an uneventful wingsuit jump, this skydiver deployed their main while appearing to be in a slightly uneven body position. The main opened with some minor line twists, but the jumper was unable to get out of them and made the decision to cutaway and deploy his reserve — but the reserve failed to fully deploy! The jumper was on his back with the reserve pilot chute in front of him, so he attempted to pull the reserve out and as he did so, he also rolled to his belly. The reserve deployed and the jumper landed safely. (We don't know where they landed, but given that it was a wingsuiter, we assume it wasn't at the dropzone.)
(We're going to skip over the line twists because, obviously, had the jumper not had line twists in the first place, this whole incident would have been prevented.) While we expect a reserve to deploy regardless of body position, here it appears that the way the jumper was positioned on their back as they pulled their reserve handle prevented the reserve pilot chute from creating enough pull force to remove the reserve pin. Consequently, the pull force is largely — probably exclusively — being exerted on his body, rather than on the pin which needs to be extracted in order to deploy the reserve.
Regarding how the failed reserve deployment could have been prevented — again, outside of not having line twists! — as is clearly visible in the video, the reserve pilot chute goes over the jumper's shoulder. As we see in the video, the second he rolled over, the reserve deployed. It seems like such a simple thing but because we all expect our reserve to be infallible, we may not think about this. This video is a great example of why not just trusting your equipment, but knowing how it works, is important in our sport.