HSS stands for:
HSS 1500 was the name of a model of Stena HSS craft developed and originally operated by Stena Line on European international ferry routes. The vessels were the largest high-speed craft in the world. Several design patents were registered to Stena Line in the development of the HSS.
Three vessels were ultimately completed in 1996 and 1997. The first of the class, Stena Explorer, entered service in April 1996, serving the Holyhead - Dún Laoghaire route and As of 2014 remains the only one still in service. Two others had served Stranraer to Belfast and Harwich to Hoek van Holland. On the 200-kilometre Hoek–Harwich route, the Stena HSS had cut the crossing time in half by cruising at 41 knots.
Stena Explorer was constructed by Finnyards in Rauma, Finland.
The HSS 1500 is a semi-small-waterplane-area twin hull (SWATH) catamaran, and was designed with the aim of providing a comfortable and fast service.
Power is provided by four GE Aviation gas turbines in a twin COGAG configuration. The vessels employ four Kamewa waterjets for propulsion.