Updated: 10 Mar 2003

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.

Steam conditions	1500 lb/sqin, 920 degF
Boiler	Water-tube with forced circulation
Fuel	Bunker C fuel oil
Turbine	Two-stage cross-compound, 12,500 rpm
Generators	Two DC 12-pole variable-voltage, 1200rpm
Traction motors	Six, air-cooled

General arrangement of the UP steam turbine locomotive.

1-6 Traction motors 7-8 Main generators 9 Alternators 10 Exciter 11 Battery charger 12 Braking resistances 13 Control contactors

14 Storage battery 15 Traction motor blower 16 Boiler 18 HP turbine 19 LP turbine 20 Exhaust header 21 Air-cooled condensers

23 Condensate tank 26 Feed water pump 27 Feed water heater 28 Boiler auxiliaries turbine 29 Condenser fan turbine 30 Air compressor 31 Train heating evaporator

33 Raw water tank 34 Boiler draught fan 36 Boiler control panel 37 Traction motor blowers 38 Fuel oil tanks

---