British Rail Class 151

The BR Class 151 was a pair of three-car DMU prototype sets built in 1985 by Metro-Cammell of Birmingham, constructed as a competitor to the BREL Class 150 Sprinter in BR's evaluation of second-generation DMU designs. Metro-Cammell, which had built much of BR's first-generation DMU fleet, proposed the Class 151 as its own interpretation of the modern regional DMU — a more technically ambitious design than the Class 150, with a stainless-steel body structure and a more sophisticated interior specification intended to demonstrate what a purpose-designed second-generation DMU could achieve.

The two three-car prototype sets — numbered 151001 and 151002 — were powered by Cummins NTA855R engines and used a Voith hydraulic transmission. The stainless-steel body, unusual for British practice, was intended to reduce maintenance costs over the life of the vehicle, and the interior was finished to a higher standard than the production Class 150. Metro-Cammell hoped that the evaluation would result in a production order that would see the Class 151 design become the standard second-generation regional DMU.

BR evaluated both sets in service alongside the Class 150 from 1985. Despite the Class 151's technical merits, the production contract went to BREL York for the Class 150 and subsequently to Metro-Cammell itself for the Class 156 — but to a simpler, cheaper design than the Class 151 prototype. The two Class 151 sets were withdrawn in 1989 after the evaluation period and both were scrapped. Neither was preserved, despite their historical significance as prototypes for the Sprinter generation.