The Union Pacific Turbine Locomotive.
These machines were the only condensing steam locomotives built and operated in the USA and were in many ways engineering triumphs but eventually proved practical failures, like almost all the turbine experiments in both the USA and Britain. The locomotives were complete electric power-stations on wheels, and correspondingly complex. A large air-cooled condenser recycled most of the water and provided (in theory, at least) a vacuum that improved turbine efficiency.
Two were built by General Electric and rolled out in December 1938.
Delivered to UP in April 1939
Returned to GE in June 1939, following unsatisfactory results
Saw extensive use on the GNR in a motive power shortage in 1943
Returned to GE and retired late 1943.
1500 lb/sqin, 920 degF
Water-tube with forced circulation
Bunker C fuel oil
Two-stage cross-compound, 12,500 rpm
Two DC 12-pole variable-voltage, 1200rpm
General arrangement of the UP steam turbine locomotive.