D199, Class 46 or Peak, nicknamed "Old Reliable" and "Spamcan", is a rude Diesel engine.
D199 was built in the early 1960s and came on trial to Sodor in 1967 with another diesel engine, Bear. D199 soon made himself an enemy of the steam engines when he claimed that "steam engines spoil our image", and he was swiftly quieted by Bear and Duck. The next day, D199 ironically failed and had to be helped home by Henry. He was soon sent home in disgrace.
D199 is based on a BR Class 46 "Peak" 1Co-Co1. Livery D199 is painted in the British Railway's "Rail Blue" livery with yellow warning panels.