Patent specification GB2493789B discloses a T-shaped boat comprising planar deck and keel in support of a single hydro-ski, and subsequent developments include a pattern for sheet materials which features a top for a foam-filled deck and a double-sided keel. Consequently in order to extend the flat-packed means of construction to operational deployments, this hydro-ski might be split into two parts able to be folded upward for storage. The same means would allow for shallow-water operation prior to deployment of the keel at a greater depth.
This hasn't just occurred to me now, but John Crawshaw Taylor from hereabouts, who invented the cordless kettle, was fond of pointing out that most patents could be got around or improved upon by a technicality.
