What is it?
This is an 1890s design of tank engine, which kept working until they were replaced by the first generation of diesel units – a long working life of 60 years or so by the standards of any locomotive. Like the F5, it is intended for use on preserved lines.
Status: quite a lot of major components partially or fully completed, including significant progress on the boiler -scroll down to the bottom of this page for a pictorial overview (then read the rest of the page for the detail!).
Possible completion date: not given, but updates on the website speak in terms of a couple of years.