At first glance, it may appear to be merely a harness pinned to the inside of a soft frame of similar dimensions and that is all there is to the device. It will not be readily apparent that it is only possible for the renowned sling separation to occur if certain opposing forces are primed to tension against each other in a particular sequence, not before, but immediately after the casualty is captured within the hollow and then only when the rescue line is being pulled in. Essentially, the primed device will transform into two separate lifting slings by pulling in a rescue line against longitudinal resistance to achieve harness elongation which overpowers side resistance (detachable mountings) and correctly places a chest sling, surrounds the immersed casualty with flotation and then masterfully provides a comfortable leg sling and hand hold for the hoist from the water. The small diameter soft frame is a major advance in thinking and requires only the lightest flip overhead to get inside the hollow.
So how does it work?
1. Only detachable side mountings connect harness to frame while both harness and frame are jointly connected to a single lifting point at the extremity of the rescue line. However, the crucial detail is that the frame straps affixed between the frame and the lifting point are longer than the corresponding lengths of the harness which protrude beyond the frame and attach the harness to the lifting point. This frees up the frame from being under any longitudinal tension even when the rescue line is taught for it is the two forward detachable harness mountings which carry first tension to the rescue line.
2. Once the immersed person is inside the hollow and the rescue line is first pulled in, the back of the frame and the back of the harness move up, as one, against the casualty’s back and the substantially rigid frame back immediately forms resistance whereupon the side mountings that hold harness to frame have no option but to break out as the pulling tension on the rescue line continues.
3. The frame and harness separate and the frame drifts backwards on its longer attaching straps while the harness elongates under tension of the rescue line being pulled in. With the harness fully elongated around the casualty’s chest, the back of the frame remains well clear of the casualty’s back allowing this rigid element to be easily plunged under water to form the leg sling and a comfortable hand hold. By ingeniously designing the floating frame to become the “sinking sling” - the opposite of what would be considered normal – the easiest way of placing a leg sling beneath an overboard person in rough seas has been achieved.
A UK PATENT has been issued for this and is now Patented by George West.
Effort required by the immersed person.
The product is primarily a first response throw out device to speedily capture someone immersed in water: in the same quick way that a lifebuoy would be thrown out. The casualty is only required to flip the small diameter soft frame overhead to enter the hollow and then to drape both arms out over the device. This automatically and correctly places the harness under both arms and as rescuers haul in the rescue line, the harness separates inwardly from the frame to lodge securely around the casualty’s chest while the frame continues to provide flotation during the haul to safety. Then, at an opportune moment before being hoisted, the frame is required to be plunged under both legs to ensure a comfortable and substantially level lift from the water: all as per video clips.