Apparently, a (uncited) wikipedia page, and the site for a heritage railway, make reference to an event where a WD 2-8-0 Austerity engine was transferred to the USATC for a S160 after the second world war. Did this actually happen? I don't think it'd be needed - a lot of the engines for either the US or the UK were pooled...
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WD-USATC Post-War engine swap?
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Moderator: Aa3rt
It did. The purpose was for testing and design comparison, presumably for planning a new fleet of locomotives for a future war.
Do any photographs or documentation exist of a WD 2-8-0 in the USA?
The locomotive in question was WD 79189, and it was shipped to the US. My information is from R. Tourret's Allied Military Locomotives of the Second World War. I can't find any photos online.