The Comet class were 12 4-4-0ST broad gauge locomotives operated on the South Devon Railway and associated railways. They were designed for passenger trains on this steep and sharply curved line but were also used on goods trains when required. They were ordered by Evans and Geach who were contracted to operate the railway's locomotives. They were designed by Daniel Gooch and based on his Bogie class locomotives built for the Great Western Railway who had previously operated the South Devon Railway.