Another springing from Litvyak's AltBC concept ...
After WWI, the British firm of Pemberton-Billing had reinvented itself as Supermarine. Wartime AD flying boats were bought back for rebuilding and refurbishment for peacetime roles. One such AD reincarnation was the Strait, Supermarine's first foray into British Columbia.
The Supermarine Strait was an AD airframe shipped in 1919 to the Hoffar shipyard in Vancouver for assembly and installation of a Liberty L-12 engine. Otherwise unchanged from the AD, the completed Strait was submitted to the RBCAF as a light patrol flying boat.
Unfortunately for Supermarine, British Columbia had no requirement for such a flying boat (being content with float-based patrol aircraft). The sole Strait was retained by the RBCAF for flying boat training at Jericho Beach but, lacking dual-controls, it was of limited use.
The Strait also participated in harbour-to-harbour air mail trials btween Victoria and Vancouver. While landing in Vancouver's Coal Harbour, fog obscured a piling until it was too late. In an unavoidable collision, the Strait's starboard mainplane was completely destroyed.
The damaged Strait was towed to the nearby Hoffar shipyard where its engine was recovered. Shorn of its ruined wings, the hulk of the Strait sat near the ways until Hoffar decided to use the hull to test its new, Fokker-style wing design. The latter was a plywood-covered wooden monoplane, necessitating a new engine-mounting structure as well.
Hoffar named its 'new' flying boat the Hornby (H-5, in the old Hoffar designation style). To subsidise development trials, Hoffar offered the Hornby as a dedicated air mail carrier to the BC government. Accepted, the Hornby flew the Victoria-Vancouver route until striking a deadhead in Victoria's Inner Harbour. The Hornby was recovered but the wing had been damaged by immersion and the hull was beyond repair.
[BTW, images based on various Zygmunt Szeremeta AD/Channel sideviews]