american invasion: the usatc s160 class 

- Alien engines on the Great Western and elsewhere

- S160 visits GWSR for 'Workhorses of Steam' Cotswold Festival of Steam 2017

Lima Locomotive Works picture of S160 no. 5740 - over 2,000 of the class were built and after the war could be found all over the world (Creative Commons)

During World War 2 the railways of Britain were for a time, invaded - by locomotives that shared none of the elegant lines of typical British designs. They were chunky, powerful-looking, robust and - oh, so American. They were the S160 2-8-0s that were constructed in considerable numbers, many shipped to Britain for the D-Day invasion of France in 1944. But while they were being stockpiled, several of them found use on British railways - and the Great Western was the largest user, employing them mainly on coal traffic from South Wales.

The class was designed by Major J W Marsh of the Railway Branch of the US Corps of Engineers, later to become the United States Army Transportation Corps (USATC).  During the 1930s, the US Army adapted a Baldwin 2-8-0 design of World War 1 vintage to create class S159, of which just eight were built in 1941. Major Marsh, in conjunction with the Lima locomotive works in Ohio, undertook a large number of improvements, including details from the 'lease-lend' S200, a 2-8-2 built for the British Army (none of which ever reached Britain), to create the S160 class. The first of them rolled off the production line in 1942. There were variations of the class too: S162 and S166 for Russia (with its broader gauge track) and S161 for Jamaica.

The S160 could hardly be labelled an aesthetic triumph. Instead, it was very much an austerity design intended for quick and economic manufacture, simple maintenance and a relatively short working life. Cast bar frames, greased axleboxes, fabricated rather than cast components and wide tyres contributed to relatively light weight and the ability to cope with the most indifferent of track. The boiler incorporated thermic siphons that supported the brick arch, although these became troublesome in practice and later boilers omitted this feature. The all-steel boiler steamed well, with or without the siphons, while the wide firebox could burn almost anything combustible, including oil. The bogie tender was large by UK standards, carrying 6,500 US gallons (5,400 Imperial gallons) of water and nine US tons (eight long, UK, tons) of coal. The cab was roomy and comfortable with controls easy to reach for both driver and fireman.

Use in the UK

In all, 2,120 S160s were produced, construction being shared between Lima, Alco (American Locomotive Co) and Baldwin. Of these, nearly 800 were shipped to Britain under a lease-lend agreement signed by President Roosevelt and Prime Minister Winston Churchill. The rest were shipped direct to Europe, North Africa and China.  

The first 398 to arrive were used by the British War Department to supplement depleted locomotive stocks and high traffic demands in the UK, although adaptations were carried out in UK works to make them suitable for use here, not least of which was turning the wheel flanges to suit UK track. Even so, they had a tendency to 'snatch' pointwork when running in reverse. Their distribution was as follows:

  • 174 - Great Western
  • 168 - London & North Eastern
  • 50 - London Midland & Scottish
  • 6 - Southern

Their use in the UK was relatively short-lived as they were all taken back into USATC stock after D-Day and shipped to mainland Europe.

The locomotives must have been a shock to GWR crews as they were quite unlike anything that had ever run on the system before. But while GWR sensibilities may not have led them to be liked, in practice they proved to be extremely powerful, surprisingly economical and entirely suitable for heavy freight traffic. They also enjoyed rapid acceleration and were also often used for troop trains and, occasionally, ordinary passenger traffic.

However, they did suffer a high failure rate - they tended to develop hot driving axle boxes while those fitted with thermic siphons tended to suffer leaks and tubeplate cracks. The locomotive steam brake was very poor - particularly when working unfitted trains. In the boilers, a major weakness was excessive corrosion and fatigue of the firebox crown bolts, especially if the boiler water level was allowed to fall too low or there was an accumulation of scale on the firebox crown. As a result, there were five incidents of the crown collapsing while in UK use, a disaster for the crew, of course, although only one such event resulted in fatality of a fireman. That actually happened near Honeybounre on the Stratford-upon-Avon to Cheltenham line with a Margam-bound freight, in December 1941.  The conclusion of the accident inquiry found that a contributory factor was the unusual gauge frame design, which could give a false reading if the screw valves (quite different to UK gauge frame valves) were not opened properly - in other words, a satisfactory water level could be indicated when the water level was, in fact, dangerously low. Incidentally, the gauge glass was designed to last the life of the

S160 2-8-0 no. 6046 during the Churnet Valley Railway's 2017 Winter Gala, 25 February 2017 (Picture: Ray O'Hara)

Another member of the class, no. 5197 is based on the Churnet Valley Railway and visited Foster Yeoman's Meerhead Quarry in Somerset in June 2008 and was put to work lifting 1,000-ton stone trains on the quarry railway system (Photo: Ian Crowder)

locomotive - rather than a protected glass tube as in UK practice, the American version was a bored solid square-section block of glass, the light refracting in a way that made the water appear black and easy to read.

Post war

After hostilities ceased, the USATC transferred most of the surviving locomotives to countries throughout Europe whose railways were struggling to get back to some kind of normality. After the war, the following countries eventually took members of the class into their own stock:

  • 576 to Poland as PKP classes Tr201 and Tr203
  • 510 to Hungary as MAV class 411 and CSD class 456 (26 broken up for spares)
  • 243 to Italy as FS class 736
  • 80 to Yugoslavia as JDZ class 37
  • 50 to Turkey as TCDD class 45171
  • 30 to Austria as ÖBB class 956
  • 27 to Greece as SEK class THg

Several locomotives surplus to USATC requirements were sold direct to other railway systems. The locomotive visting the GWSR for the 2017 Cotswold Festival of Steam is no. 6046, which never ran in the UK but was delivered straight to France from the builder, Baldwin, arriving in 1945.  After the war, French National Railways (SNCF) sold the engine to Hungarian State Railways (MAV) where it become no. 411.144.  The locotive was evenutally privately bought out of industrial use and shipped to the UK; and after partial restoration at Tyseley, was bought by Greg Wilson in 2006 for use on the Churnet Valley Railway.  The engine steamed for the first time in Britain in 2012 and has been a reliable performer ever since. 

Although many only survived for a very short time, a good number continued in use until relatively recently and several survive either preserved by railway museums across Europe and in America or are dumped. Six have been imported or re-imported to the UK, some of which saw service on British railways before D-Day.

Only a small handful ever found their way back to their country of birth.

Vital statistics

Cylinders (2) 19 x 26in
Valve gear Walschaerts
Boiler Superheated, 225psi
150 smoke tubes
30 flue tubes
Grate 41 sq. ft.
Leading Wheels 2ft 9in
Driving Wheels 4ft 9in
Tractive Effort 31,490lbf
Wheelbase Length 51ft 8in
Weight 124tons 12cwt
Axle Load 15tons 15cwt