British Rail HS4000 “Kestrel”

For use as a future type 5 locomotive, Brush Traction built a single technology demonstrator in 1967. It was designated HS4000 after Hawker Siddeley, the owner of Brush and the horsepower rating of its engine. The engine was an oil-cooled V16 from Sulzer, with the idea that a single engine would be easier to maintain than two. To enable a top speed of 110 mph (177 km/h), it had hollow shaft drive and dynamic brakes. 

After being handed over to British Railways, it was tested in freight and passenger service. No additional orders followed since its axle load was too high for many British lines. In 1971, it was sold to the Soviet Union where it was put on display, re-gauged to Russian gauge and tested. After some years of service, it was finally scrapped.