Designed primarily as a fast ferry for operations in sheltered waters, the SR.N6 Mk I can accommodate either 38 passengers or 3 tonnes of freight. Fully amphibious, it can operate from relatively unsophisticated bases above the high water mark, irrespective of tidal state.

Directional control is achieved by twin rudders and skirt lift, with a thrust port system to assist in low speed manoeuvring. Two manually actuated elevators provide pitch trim at cruising speed.

SR.N6s have been in regular civil operations since 1965. Operators have included Hoverwork Ltd and the Canadian Coast Guard.

Military variants have seen service with the Egyptian Navy, Iraqi Navy (type Mk 6C), Iranian Navy and the Saudi Arabian Frontier Force.