GE U18B

GE U18B
A Maine Central Railroad U18B, on lease to the short-lived Niagara and Western New York Railroad, July 2002
Type and origin Power type Diesel-electric Builder General Electric Model U18B Build date March 1973 – October 1976 Total produced 163
Specifications Configuration: ​  • AAR B-B  • UIC Bo′Bo′ Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge Length 54 ft 8 in (16.66 m) Prime mover GE 7FDL Engine type V8 4-stroke diesel Aspiration Turbocharger Displacement 5,344 cu in (87.57 L) Cylinders 8 Cylinder size 9 in × 10.5 in (228.6 mm × 266.7 mm) Transmission DC generator, DC traction motors Loco brake Straight air, Dynamic Train brakes 26-L Air
Performance figures Power output 1,800 hp (1.34 MW)
Career Locale North America

The GE U18B diesel-electric locomotive was introduced by GE Transportation as a branch line roadswitcher in 1973. Easy to spot due to its relatively short length — 54 ft 8 in (16.66 m) — it was the only North American locomotive powered by the 8-cylinder 7FDL engine.

The Seaboard Coast Line Railroad (SCL) bought 105 U18Bs, far more than the second-best U.S. customer, the Maine Central Railroad (MEC), which ordered 10. Most of the SCL and MEC U18Bs rode on refurbished Blomberg trucks, recycled from old EMD locomotives, making the U18B even more visually distinct from other GE locomotives.

Many railfans refer to the GE Universal Series locomotives as "U-Boats." Due to its smaller size, the U18B received the nickname "Baby Boat."

Not many U18Bs still exist, but some short-line railroads, such as the Pickens Railway, still have several U18Bs in everyday service.

GE included information about a B18-7 locomotive (which would have followed the U18B) in its 1978 "Series-7 Road Locomotives" service manual, but none of these updated units were ordered, sold, or built.