Editing SR.N4 (section)

===Prototype and testing===
Having realised that the market for large hovercraft was not yet large enough to sustain a number of competing companies at that time, in 1966, the hovercraft divisions of both [[Saunders-Roe]] and [[Vickers Supermarine]] merged to form a new united entity, known as the [[British Hovercraft Corporation]] (BHC), which was headquartered on the [[Isle of Wight]].{{sfn|Paine|Syms|2012|p=165–166}} In autumn 1966, production work commenced on the structure of the first SR.N4, which was internally designated ''001''. The vehicle was assembled in the same hangar in which the three [[Saunders-Roe Princess]] [[flying boat]]s had been constructed 15 years before.{{sfn|Paine|Syms|2012|p=236}}{{sfn|Paine|Syms|2012|p=238}} During 1967, as 001 was taking shape, it was announced that the SR.N4 had been named the ''Mountbatten-class''.{{sfn|Paine|Syms|2012|p=238}} Throughout the development and production of 001, both Hoverlloyd and [[Seaspeed]] carefully monitored progress on the project.{{sfn|Paine|Syms|2012|p=295}}

In October 1967, the completed 001 was officially presented to gathered members of the press and to various representatives and dignitaries.{{sfn|Paine|Syms|2012|p=249}} On 20 November 1967, the first engine run was performed, after which 11 weeks of intense test runs on land were performed and the exposed faults were addressed. On 4 February 1968, 001 was launched onto water for the first time.{{sfn|Paine|Syms|2012|p=249}}{{sfn|Paine|Syms|2012|p=297}} The launch, while successful, had involved some risk due to the lack of space to manoeuvre with an untested control system. Later that same day, 001 conducted its [[maiden flight]].{{sfn|Paine|Syms|2012|p=249}}{{sfn|Paine|Syms|2012|p=297–300}}

As experience with the prototype accumulated, the control arrangement proved to be quite effective even within confined spaces; incidents involving a loss of control did occur during the test programme, but these were mainly due to error on the part of the operator.{{sfn|Paine|Syms|2012|p=303–305}} Ray Wheeler, BHC's chief engineer, was reportedly very pleased with the progress made during the initial trials. At the same time, 001 required substantial refinement and alteration in order to become a commercially viable craft.{{sfn|Paine|Syms|2012|p=305}} The air intakes had to be substantially modified in order to minimise [[salt]] ingestion, and a revised skirt system was also developed.{{sfn|Paine|Syms|2012|p=305}}