"三帆快速战舰" can be translated as "Three-Masted Fast Warship" or more specifically in a nautical or historical context, it might be rendered as "Three-Masted Swift War Vessel" (though "warship" is more commonly used in modern English for such vessels). However, "Three-Masted Fast Warship" is a straightforward and generally acceptable translation.
If it refers to a specific historical type of ship with a particular name or classification in historical texts, the exact translation might vary slightly depending on the context and the specific terminology used in historical naval records. But for a general translation, "Three-Masted Fast Warship" is appropriate.