faREWELL ‘big fOUR’

‘Big Four’ era comes to a close with two all-new designs…

It’s December 1947, and with just one month to go before the LMS ceases to exist, the largest member of the ‘Big Four’ is still as active as ever in locomotive design and construction – bequeathing new steam and diesel classes to the emerging British Railways.

After nearly a quarter of a century, the ‘Big Four’ era – often regarded as the golden age of railways in Britain – came to an end on December 31 1947. For the next five decades, from New Year’s Day 1948, Britain’s railways would be nationalised and under Government control. It is apt that the dawn of this new age would be prefaced by a pair of designs – one evolutionary, the other revolutionary – both in their own ways pointing the way forward for British railway transportation. The first was LMS No. 3000, the prototype of H.G. Ivatt’s ‘4MT’ class 2-6-0s – the last new steam locomotive design for the London Midland & Scottish Railway. Outshopped on December 12 1947, No. 3000 (later BR No. 43000) was the first of three ‘Flying Pigs’ to be built under LMS auspices, the remaining 159 examples were BR-built. The last was No. 3002, which emerged from Horwich Works on December 31 1947 as the final LMS locomotive. Indeed, No. 3002 was one of the last – if not the ultimate – steam locomotive produced by any of the ‘Big Four’. The second design was also Ivatt’s work: English Electric Co-Co No. 10000 – the first main line diesel built for use in Britain. While the ‘Flying Pigs’ represented the short-term future for British Railways, No. 10000 was the ancestor of almost all the BR diesels which superseded steam. Ironically, neither it nor twin sister No. 10001 outlived the steam engines they were intended to replace, while the ‘4MTs’ would influence the design of the Riddles Standard ‘Moguls’, and several ‘Flying Pigs’ would last until the end of BR steam – including preserved example No. 43106.