Northern Pacific Baldwin DRS-4-4-1500 501, probably at Marshall, Washington, date unknown. Photographer was probably Phil Hastings.

This was one of only 35 Baldwin DRS-4-4-1500's built. This engine was built by Baldwin in September, 1948, as NP 176 as a two unit order for Northern Pacific 175-176.

NP 501 was re-engined with an EMD 567-BC in 1966.

(Craig Garver, Public domain,


BALDWIN DRS-4-4-1500

The Baldwin DRS-4-4-1500 was a diesel-electric locomotive of the road switcher type rated at 1,500-horsepower (1,100 kW), that rode on two-axle trucks, having a B-B wheel arrangement. It was manufactured by Baldwin Locomotive Works from 1947 until it was replaced in 1950 by the 1,600-horsepower (1,200 kW) AS-16.

Nine railroads bought 35 locomotives, with five railroads later buying the successor model.


Seaboard Air Line Baldwin DRS-4-4-1500 1471 at St Petersburg, Florida, September 1, 1962. Photographer: T King.

(Craig Garver, Public domain,


Railroad Quantity Road numbers Notes
Erie Railroad 6 1100–1105
Lehigh Valley Railroad 1 200
Iron Mines of Venezuela (Bethlehem Steel Company) 3 1–3
Minneapolis, St. Paul and Sault Ste. Marie Railroad ("Soo Line") 8 360–367
Missouri Pacific Railroad (St. Louis, Brownsville and Mexico Railway) 4 4112–4115
New York Central Railroad 2 7300–7301
Northern Pacific Railway 2 175–176 Renumbered 500–501 to Burlington Northern 405-406
Pennsylvania-Reading Seashore Lines 6 6000–6005
Western Maryland Railway 3 170–172
Total 35

Baldwin DRS-4-4-1500 Overview

Type and origin
Power type: Diesel-electric
Builder: Baldwin Locomotive Works
Model: DRS-4-4-1500
Build date: July 1947–May 1950
Total produced: 35
​• AAR B-B
• UIC Bo′Bo′
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Length: 57 ft 10+3⁄4 in (17.65 m)
Height: 14 ft (4.27 m)
Locomotive weight: 120 short tons (107 long tons; 109 t)
Prime mover: Baldwin 608SC
Engine type: Four-stroke diesel
Aspiration: Turbocharged
Displacement: 15,832 cu in (259.44 L)
Alternator: Westinghouse YG42A
Generator: Westinghouse 471A
Traction motors: Westinghouse 370F (4)
Cylinders: 8
Cylinder size: 12+3⁄4 in × 15+1⁄2 in (324 mm × 394 mm)
Transmission: Electric
Locomotive brake: Straight air
Train brakes: Air
Performance figures
Maximum speed: 65 mph (105 km/h)
Power output: 1,500 hp (1,100 kW)
Tractive effort: 61,510 lbf (273.61 kN)


Burlington Northern Baldwin DRS-6-6-1500 407 at Pasco, Washington, June 30, 1971. Photographer: Ed Kanak.

(Craig Garver, Public domain,