4B73

4B73 is a MotivePower MP15 locomotive, also known as the MP15AC. It is a diesel-electric switcher with a total power output of 1,500 horsepower. Manufactured by Electro-Motive Division (EMD), the MP15AC is a member of the EMD family of switcher locomotives.

The 4B73 began its service life with the BNSF Railway (BNSF) as part of a larger order. Built in the 2000s, the locomotive featured several modern amenities including a 3,200-liter fuel tank, a 9-cubic-yard trash hopper, and a derailer. This combination provided an efficient and versatile platform for hauling heavy freight trains on the BNSF rail network.

4B73 has since undergone significant changes, including a transfer of ownership to the Norfolk Southern Railway (NS) in the United States. This transition took place as part of a broader exchange of locomotive assets between the two railroads. According to reports, the locomotive's primary duty has shifted towards yard switching and light-hauling assignments.

Throughout its operational history, the 4B73 has maintained reliability and dependability. Its overall on-time performance has reflected positively on both BNSF and NS attributed to the locomotive's efficient design and operation.

In terms of technical specifications, 4B73 conforms to typical industry standards, utilizing a 16-cylinder EMD 16-645 diesel engine. Supplementing this diesel powerplant is a DC traction system, along with a 1,000 Amp HR Smith reverser. With such modern systems on board, it chronicles its era while operating over the North American rail network.