The British Rail Class 47 (Originally Brush Type 4) is a class of British railway diesel-electric locomotive that was developed in the 1960s by Brush Traction. A total of 512 Class 47s were built at Crewe Works and Brush's Falcon Works, Loughborough between 1962 and 1968, which made them the most numerous class of British mainline diesel locomotive.
They were fitted with the Sulzer 12LDA28C twelve-cylinder diesel engine producing 2,750 bhp (2,050 kW) (later derated to 2580 bhp to improve reliability), and have been used on both passenger and freight trains on Britain's railways for over 40 years. Despite the introduction of more modern types of traction, as of 2008 a significant number are still in use, both on the mainline and on heritage railways. As of December 2008, 103 locomotives still exist, with 29 working on the mainline.