British Rail 11001

11001 was one of the first British Railways diesel locomotives, built in 1949 at British Railways' Ashford railway works. It was designed by Oliver Bulleid when he was Chief Mechanical Engineer of the Southern Railway. It was powered by a Paxman RPH Series 1 engine, capable of delivering at 1,250 rpm. It was driven via a Vulcan-Sinclair fluid coupling to an SSS Powerflow gearbox. The gearbox provided three forward and reverse gears in either high or low range, with top speed ranging from in 1st gear, low range up to. It had a 0-6-0 wheel formation, driven by rods from a rear jackshaft on the final drive, and with Bulleid's favoured BFB wheels.
Its main duties were on branch lines and shunting around Norwood Junction, working goods services on the Caterham line during the 1950s. During 1952, it was trialled at Stourton marshalling yard in Leeds. Following a gearbox failure in 1958, it was stored at Ashford, before withdrawal in August 1959. It was cut up at Ashford in December 1959.