EMD SD70ACU

EMD SD70ACU
NS SD70ACU No. 7305 pulling train 238
Type and origin Power type Diesel-electric Builder General Motors Electro-Motive Division/Norfolk Southern Model EMD SD70ACU Build date 2015-present Total produced 170
Specifications Configuration: ​  • AAR C-C  • UIC Co′Co′ Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Trucks EMD Radial Steering Wheel diameter 42 in (1,067 mm) Length 80 ft 2 in (24.43 m) Width 10 ft 2 in (3.10 m) Axle load 32 tonnes Fuel capacity 4700 gallons Prime mover EMD 16-710 G3B Engine type V16 diesel engine Aspiration Turbocharged Cylinders 16
Performance figures Maximum speed NS 75 MPH, CP 65 MPH Power output 4,300 hp (3,207 kW)
Career Locale North America Disposition 170

The EMD SD70ACU is a 6-axle 4,300 hp (3,207 kW) road switcher diesel-electric locomotive originally built by General Motors Electro-Motive Division as an SD90MAC, and rebuilt by Norfolk Southern and Progress Rail Services. They are operated by two railroads, Norfolk Southern and Canadian Pacific Railway.

The SD70ACU began under Norfolk Southern, who rebuilt their SD90MACs to this configuration at its shops in Altoona, Pennsylvania. The first locomotive entered the rebuilding process in September 2015, which was the 7299. As of 2019, all 110 units have been released into active service on the Norfolk Southern.

All of the SD70ACUs will be rebuilt with the latest EMD cab which meets current FRA crashworthiness standards. The Siemens electronics will be replaced with Mitsubishi electronics. The rebuild also includes the installation of Ultra Cab II, locomotive speed limiter (LSL), and cab signals. The trucks will be rebuilt only as-needed and they are not getting traction motors swapped out.

In 2018, CP started a similar rebuild program with their long dormant SD90MAC fleet. Unlike NS, the work on these rebuilds will not be done in-house, but by Progress Rail at their Mayfield, Kentucky and Muncie, Indiana facilities.

Norfolk Southern

An EMD SD9043MAC, the units that are being rebuilt into the SD70ACU.

The units that were chosen for the Norfolk Southern rebuilding program are either ex-Union Pacific or from the CIT Group CEFX fleet of EMD SD90MAC locomotives. The SD90MAC was introduced in 1995 and was designed to use the new 16-cylinder, 6,000-horsepower (4,500 kW) H-engine. However, technical problems with the 265 engine resulted in the locomotives being delivered with the 4,300 hp (3,210 kW) 16-cylinder 710G used in EMD's SD70MAC model. UP referred to these locomotives as SD9043MACs, and EMD planned to offer customers the option to upgrade them to the 6,000 hp (4,470 kW) 265 engine at a later date. EMD's upgrade program, however, was never carried out due to unresolved reliability issues with the 265. Over 400 SD90MAC locomotives fitted with the 4,300 hp (3,210 kW) 710 engine were built. Of the 309 SD90MACs Union Pacific had acquired, 100 units were sold to Norfolk Southern as part of the SD70ACU rebuild program. EMD was responsible for delivering the locomotives, all units have been delivered by November 2015. They are numbered 7229-7328. In July 2016, Norfolk Southern acquired another 10 SD90MAC locomotives from CIT Financial and the Indiana Railroad for the continuation of the SD70ACU program. They will be numbered 7329-7338.

As of 3 May, 2017, units that have received a full engine overhaul meet Tier 1+ emission standards, while units that have not yet received a full engine overhaul meet Tier 0+ emission standards. While all of the rebuilds are being upgraded to 4,500 traction horsepower, the Tier 0+ units generally only make 4,300-4,400 horsepower. Those units that have been overhauled and meet Tier 1+ emission standards are 7233, 7235, 7243, 7250, 7253, 7258, 7293, 7296, 7298, 7305, 7308, and 7319.

As originally built by EMD, the SD90MAC had a fuel tank capacity of 5,700 gallons. While owned by Union Pacific, the units started developing cracks in the frames around the fuel tank mounts. UP worked with EMD to solve the frame cracking problem by adding additional mounting brackets between the frame and fuel tank. In addition, the fuel filler pipes were modified to only allow a maximum of 4,700 gallons of fuel to be added.

As originally built by EMD, the SD90MAC had a maximum weight of 415,000 pounds. After being rebuilt in the SD70ACU program, the maximum weight initially increased to 420,000 pounds due to the additional weight of the new widenose and cab. Starting with the 35th SD70ACU rebuild, NS began adding additional weight to each end of the units to increase the maximum weight to 432,000 pounds. The first 34 units will also have the additional weight added as shop time permits. Those units that have received the additional weight are 7231, 7232, 7233, 7234, 7236, 7241, 7242, 7243, 7244, 7246, 7247, 7249, 7253, 7254, 7259, 7271, 7272, 7274, 7277, 7278, 7285, 7296, 7302, 7303, 7304, 7306, 7308, 7311, 7312, 7314, 7316, 7317, 7318, 7322, 7326, and 7328.

The original cab and electrical cabinet were replaced with new EMD SD70ACe style isolated cab AAR-style control stand, and electrical cabinet with Mitsubishi electronics. They retain their original TA22 main alternator and 1TB2830 traction motors. As well they are equipped with a CCB II computer controlled braking system and the GE Ultra Cab II Cab Signaling, LSL (Locomotive Speed Limiter) as well as Automatic Engine Stop/Start. All units are equipped with NS LEADER/PTC (Positive train control) system and are equipped for use in DPU (Distributed Power Unit) operation. A new electric parking brake has been added with brake wheel on the left side of the long hood. Ditch lights have also been added to the rear during rebuilding.

Canadian Pacific

CP 9112, a SD90MAC, being transported south on the CP Emerson Subdivision to be rebuilt to an SD70ACU.

In 2018, it was announced that Canadian Pacific came to an agreement with Progress Rail to rebuild 30 of Canadian Pacific's long dormant SD90MAC fleet into a similar rebuild as what the Norfolk Southern had done. The new Canadian Pacific SD70ACUs are numbered 7000-7029. In 2019, Canadian Pacific decided to rebuild their remaining 28 Canadian Pacific SD90MACs. Canadian Pacific had originally purchased 61 SD90MACs but since they had been in long term storage since 2012, several units were unfit for rebuilding, this is why they purchased two SD90MACs from Union Pacific for another batch of 30 rebuilds, these are to be numbered 7030-7059.

The Canadian Pacific units will feature crew comforts and safety features such as the Progress Rail “Q cab," featuring an AAR control stand, an emergency access door located behind the conductor’s seat, forward and inward facing cameras, an electrically assisted hand brake, and full-length window awnings. Also included are new control electronics, Mitsubishi AC propulsion components, NYAB CCBII electronic air brakes, and positive train control. These units are also equipped with Progress Rail’s EM2000 Control System and FIRE display screens. Each rebuild will weigh 432,000 lbs., have a maximum speed of 65MPH, and be rated at 4500 horsepower. These units will meet Tier 1+ emission standards.

In August 2019, Canadian Pacific received the first four SD70ACUs and subsequently assigned them to coal train service in British Columbia for testing. On September 16, 2019, Progress Rail rolled out two SD70ACU rebuilds in Canadian Pacific heritage paint schemes. Units numbered 7010 to 7014 wear a Tuscan red and grey paint scheme with script writing that was used between 1960 and 1968. Units numbered from 7015 to 7019 wear a similar paint scheme with block lettering that was used between 1949 and 1959.

On November 11, 2019, five units with commemorative military themes were released during Canadian Pacific's Remembrance Day Ceremony, these units are numbered 7020-7023, with 7024 being renumbered to 6644 or June 6, 1944 in honor of D-Day. The 6644 represents a memorial to WWII, it sports a paint scheme derived from the Allied Spitfire using Royal Air Force Dark Green, Ocean Grey and accented with Roundel Yellow with a font that is RAF standard to planes used in WWII. The 7020 represents the Army in Temperate Regions, it is painted in NATO Green and features a modernized Army font. The 7021 represents the Army in Arid Regions and painted in a Desert Sand Colour and features a modernized Army font like the 7020. The 7022 represents the Navy, it is painted in Royal Canadian Navy Shipside Grey and Oxide Red and uses the correct navel font. The 7023 represents the Air Force, it is painted in the same colours as a CF-18 which uses Light Ghost Grey and Medium Grey as well featuring the correct RCAF font. All five commemorative military units feature Canadian Pacific's unique Support Our Troops logo.

See also

• EMD SD70 series - A list of the many variants of SD70s EMD has produced

References

• "Juniata Diesel Conversions SD90MAC to SD70ACU for Norfolk Southern". 2015. Retrieved 2015-09-22.

• NSDASH9.com is a major source of information.
• Media related to EMD SD70ACU locomotives at Wikimedia Commons