GE Dash 9 Series (C40/C44-9W)

Introduced in the mid-1990s, the GE Dash 9 Series remains one of the most popular locomotives on the rails. This 4,400 horsepower, direct current (DC) traction locomotive continues to command the rosters of various railroads, and are known for their reliability and versatility. The series acted as the replacement for the venerable Dash 8 series, which introduced the GE wide cab design in 1990. The Dash 9 locomotive was purchased by various railroads throughout North America, South America, and Australia, including Norfolk Southern, Atchison Topeka & Santa Fe, BNSF, Southern Pacific, Canadian Pacific, Chicago Northwestern,  Estrada de Ferro Vitória a Minas in Brazil, and various iron ore carriers in Western Australia.

Development of the Dash 9 began when the Chicago Northwestern anticipated the need for additional horsepower for their Powder River Basin coal trains. The railroad began upgrading their current Dash 8 locomotives from 4,000 to 4,125 horsepower, however, improvement in power output was inadequate. Thus, the CNW contacted GE, and the two organizations began developing a higher horsepower successor to the C40-8/8W locomotive. Thus, the C44-9W was developed as the first production locomotive to have 4,400 horsepower, and was first delivered to the CNW and various other railroads in 1993.

The Dash 9 included various improvements over the Dash 8 locomotive, such as improved cooling, high adhesion (Hi-Ad) trucks which included special springs and suspension, providing a smoother ride, and an updated braking system. The locomotive was technologically advanced, as the analog controls of the Dash 8 were replaced with computer screens, which gave the crew readings on train speed, RPM, end of train device (EOT) information, and brake pipe status. One of the most significant advantages of the locomotive was the addition of a upgraded alternator, which allowed the locomotive to reach its allotted 4,400 horsepower rating. The development of the Dash 9 solidified GE as the world’s premier locomotive builder, surpassing longtime rival EMD.

In a sense, the Dash 9 series of locomotives is an upgraded version of the reliable and versatile Dash 8 series, which lead many railroads to place large orders for the new locomotive. Norfolk Southern ordered 1,215 examples, 125 standard cab, and 1,090 wide cab versions. Due to the addition of an air conditioner on the top of the standard cab, railfans began calling the 125 locomotives “top hats”, due to their unique appearance. Norfolk Southern was the only railroad to order standard cab versions, as it was less expensive than the wide cabs. However, pressure from the Federal Railroad Administration (FRA), and the fact that the standard cab was more expensive than the wide cab due to it being an option, led Norfolk Southern to modify the order for widecabs instead.

Interestingly, the Norfolk Southern examples were rated at 4,000 horsepower as opposed to the standard 4,400, thus designating them C40-9W. This was due to Norfolk Southern management’s belief that saving the extra 400 horsepower from the prime mover would extend the life of the engine while increasing fuel efficiency. Furthermore, the prime mover could easily be uprated to 4,400 due to an override switch accessible from the cab. In 2015, Norfolk Southern decided to increase the horsepower of the fleet to 4,400, as the override switch was flipped as each locomotive ran through its regular maintenance cycle.

The standard cab Norfolk Southern Dash 9s have since been rebuilt into AC44C6M rebuilds by the railroad’s Juniata and Roanoke Shops. The rebuilds include a GE wide cab and alternating current (AC) traction equipment. In addition to the 125 standard cab rebuilds, several wide cabs were rebuilt as AC44C6M.

Further orders for the locomotive came from ATSF, and later BNSF, who currently command a 1,697 strong fleet of the type. Several examples have been rebuilt into AC44C4M locomotives by GE, which includes an A-1-A A-1-A wheel arrangement similar to the ES44C4, where the middle axle in each truck lacks a traction motor.

Further orders of Dash 9s were ordered by Canadian National, Southern Pacific, and BC Rail. A number of BC Rail versions were designated C44-9WL, which included the four window Canadian safety cab, and two sets of ditch lights. Union Pacific inherited many of the Dash 9s from the CNW and Southern Pacific, after their merger with UP. Canadian National now rosters the BC Rail Dash 9s after they assumed its operations in 2004.

Although the Dash 9 was a popular locomotive, models built after 2000 were fraught with cooling issues. In an effort to further improve the efficiency and reliability of the fleet, GE opted to include larger cooling systems. However, this system was inadequate for proper cooling, resulting in failures such as engine explosions, overheating of various components, and fires. The issue was rectified when GE ordered updated cooling systems from more reputable manufacturers, and repaired customer’s locomotives at no cost.

The Dash 9 was the last highly successful direct current (DC) locomotive, as its successor, the AC4400CW provided superior tractive effort and was a viable competitor against EMD’s SD70MAc.

Technical

The C40/C44-9W designation denotes, C for C-C AAR wheel arrangement, 40 or 44 for 4,000 or 4,400 horsepower, 9 for the Dash 9 series, and W, for wide cab. Operation of the locomotive consists of GE’s venerable 4 cycle 7-FDL16 prime mover supplying power to a GE – GMG197 main generator, which delivers direct current (DC) traction to the 6 GE 752AH traction motors, supplying 142,000 lbs of tractive effort to the rail.

One of the most prevalent upgrades from previous GE models was the addition of the Hi-Ad trucks, which provided increased traction power and a smoother ride for the crew. The addition of an updated GYA30A alternator provided the capability for the locomotive to generate 4,400 horsepower.

The addition of the various electronics supplied train crews with more information than ever before, as the interactive computerized screens allowed the crew to configure various readings, neatly displayed in a modern format.

Technical Information Courtesy of The Diesel Shop