zTTS Cls Rail Cl.37 Co-Co 3752HOR R30041TTS Hornby Colas Rail, Class 37, Co Co, 37521 Era 11 Entering service as the English Electric Type 3, the British Rail Class 37 diesel locomotives were built at the Vulcan Foundry in Newton le Willows in a Co Co configuration, based on locomotive designs for export markets. Built to undertake both freight and passenger work across all BR sectors, these engines proved highly reliable and, after overhaul, many survived in service across the