J class

J class or Class J may refer to:

Locomotives

• NZR J class (1874), steam locomotives operating in New Zealand from 1874 until 1935
• NZR J class (1939), steam locomotives operating in New Zealand from 1939
• WAGR J class, steam locomotives operating in Western Australia from the 1890s
• WAGR J class (diesel), diesel locomotives operating in Western Australia from the 1960s
• Victorian Railways J class, branch line steam locomotives operating in Victoria, Australia from 1954 to 1972
• N&W J class (1879), steam locomotives operating on American Railroads from 1879 until 1900
• N&W Class J (1903), steam locomotives operating on American Railroads from 1903 until 1935
• N&W J class (1941), steam locomotives operating on American Railroads from 1950 until 1959

Watercraft

• J-class yacht, a racing yacht design constructed for the America's Cup competition between 1931 and 1937
• J, K and N-class destroyer, a class of British-built destroyers active from 1937 until 1949
• British J-class submarine, a class of British-built submarines operated by the Royal Navy and Royal Australian Navy between 1916 and 1930
• Jymy-class motor torpedo boat, an Italian World War II boat

Other uses

• J-class blimp, 1920s airship
• Class J, a fictional planet category from Star Trek, consisting of small gas giants