English Electric Deltic

The English Electric Deltic is a British diesel-electric locomotive, built by English Electric and introduced into regular service with British Railways in 1961 as Class 55, named for the distinctive Napier Deltic opposed-piston diesel engines that powered it. Built with two of these compact, high-power Deltic engines per locomotive, an unusually powerful combination for a British main-line diesel of its era, the Deltic gave British Railways locomotives with a power-to-weight ratio well ahead of contemporary diesel designs, allowing them to haul express passenger trains on the East Coast Main Line between London, Yorkshire and Scotland at higher speeds and with better reliability than the aging steam locomotives they replaced. Only twenty-two production Deltics were built, and their combination of distinctive engine sound, striking two-tone livery and high-profile express passenger duties made them among the most celebrated and popular British diesel locomotives with railway enthusiasts, with several examples preserved and returned to main-line operation after withdrawal from regular service.