GE AC6000CW. The AC6000CW is a  diesel electric locomotive built between 1995 and 2001 by GE Transportation. It is among the world's most powerful single-engined diesel locomotives. The locomotive was designed for extremely high horsepower needs, such as pulling heavy coal and ore trains. Most examples were purchased by two railroads: Union Pacific and CSX.

Design and production
The AC6000CW was designed at the height of a horsepower race between the two major locomotive manufacturers, Electro-Motive Division of La Grange, Illinois with the SD90MAC, and GE Transportation of Erie, Pennsylvania with the AC6000CW, in the early to mid 1990s. The goal was .

GE worked with Deutz-MWM of Germany in 1994 to design and construct the  7HDL engine for the locomotives. The first locomotive with a 7HDL was the "Green Machine" GE 6000, nicknamed for its green paint scheme. The first production models were also built in 1995: CSX Transportation 600-602, and Union Pacific Railroad 7000-7009. All these locomotives were released to their respective owners in late 1996, once GE's testing was complete.

GE built 106 AC6000CWs for Union Pacific, but with the older, proven 7FDL engine installed, rated for . These units were originally intended to be converted to the  7HDL engine after some problems with the 7HDL were solved, but the conversion never occurred. GE calls these units AC6000CW "Convertibles", while UP classifies them as C6044ACs or AC4460CWs.

The AC6000CW ended production in 2001. Union Pacific designates their units as C60AC, CSX as CW60AC and CW60AH.

Service history 

The initial locomotives suffered from various mechanical problems with the most severe being the engine itself. There were major vibration problems which were addressed by increasing the engine mass to lower the resonant frequency. This in turn caused problems with the twin turbochargers. These problems caused GE to push back full production of the new model until 1998. Changes such as stiffer materials and increased engine wall thickness (to increase mass) were in place at full production.

CSX Transportation had re-powered many of their AC6000CW units from 16-7HDL engines to GEVO-16 to make them more reliable and environmentally friendly. These units were capable of  but had been rated at  and classified as CW46AHs. Union Pacific also had their 16-7HDL AC6000's repowered with FDL-16's, creating an entire fleet of 4,400-hp AC6000CWs. 

Beginning in 2018, Union Pacific had begun sending its AC6000CWs to GE for rebuilding. The rebuilt units are classified as C44ACMs. By 2023, all of the units have been rebuilt. 

By 2024, CSX had scrapped or sold off all of their AC6000 except for three of their pre-production AC6000CWs that were repowered with FDL16 engines. The rest were either sold off to leasing company Progress Rail Services (PRLX), the Western New York and Pennsylvania Railroad (WNYP), or scrapped.

World record 
On June 21, 2001, all eight of the Australian mining company BHP Billiton's Mount Newman railway AC6000s worked together to set the world record for the heaviest and longest train. They hauled  and 682 wagons for  between Yandi mine and Port Hedland. The train was  long and carried  of iron ore. The record still stands . These are the only AC6000CWs that were exported outside of the United States. They are the most powerful locomotives to have operated in Australia.

Operators

Preservation 
GECX #6002 (ex-Union Pacific #7511) was donated by GE to the Lake Shore Railway Museum in North East, Pennsylvania in 2022. It is the first modern AC traction locomotive to enter preservation.

The Aberdeen Carolina and Western Railway has created their "Engine Room 87" out of the scrapped husk of former PRLX 656/CSX 666 for the US Open special train.

See also

Notes

References

BHP Billiton diesel locomotives
C-C locomotives
Diesel–electric locomotives of the United States
Diesel locomotives of Western Australia
AC6000CW
Freight locomotives
Railway locomotives introduced in 1995
Standard gauge locomotives of the United States
Standard gauge locomotives of Australia
Diesel–electric locomotives of Australia