The British Rail Class 55 is a class of diesel locomotive built in 1961 and 1962 by English Electric for British Rail. They were designed for the high-speed express passenger services on the East Coast Main Line (ECML) between Edinburgh and London King's Cross. They gained the name "Deltic" from the prototype locomotive, DP1 Deltic (the running number DP1 was never carried), which in turn was named after its Napier Deltic power units. Twenty-two locomotives were built, which dominated express passenger services on the ECML. Until 1978 when Class 43 High Speed Trains (HSTs) were introduced. They were subsequently relegated to semi-fast services on the Kings Cross to York, Edinburgh and Hull routes and continued on sleeper services along the ECML. Other occasional destinations, although with no officially diagrammed work, included Cleethorpes, Stockport, Liverpool Lime Street and Aberdeen. They rarely worked to Skegness and Scarborough. Expect Random Stuff on my Channel