The reference for locomotives and railcars
United States | 1946 | 297 produced
New Haven PA-1 as class DER-3a No. 0779 and 0775 in June 1950 in Tremont, Massachusetts
New Haven PA-1 as class DER-3a No. 0779 and 0775 in June 1950 in Tremont, Massachusetts
Ralph H. Payne / collection Taylor Rush

With the development of the new Type 244 engine, ALCO introduced the PA passenger locomotive in addition to the FA freight locomotive in 1946. Not only did the propulsion electrics come from General Electric, the streamlined and modern design of the car body also came from Ray Patten, head of GE's design department. The PA got the more powerful sixteen-cylinder engine and stood on two bogies with the A1A wheel arrangement. What all PA and FA have in common is that black smoke came out when accelerating due to the lack of air in the turbo lag.

With a 2,000 hp engine, 169 PA1 and 39 PB1 without a cab were built. From 1950 onwards, 81 PA2 and eight PB2 were built with 2,250 hp. Three PA-2s went to Brazil with a gauge of 5 ft 3 in. Some railroads also used their PA and PB in freight traffic, but the number of units remained behind EMD's E series due to lower reliability. The Massachusetts Bay Transit Authority used its locomotives until the late 1970s and then sold them to the Ferrocarriles Nacionales de México, which continued to use them until 1981.

ManufacturerALCO, General Electric
Axle configA1A-A1A 
Gauge4 ft 8 1/2 in (Standard gauge)4 ft 8 1/2 in (Standard gauge), 5 ft 3 in (Irish broad gauge)
Dimensions and Weights
Length65 ft 8 in
Wheelbase49 ft 6 in
Fixed wheelbase15 ft 4 in
Service weight300,700 lbs306,000 lbs
Power sourcediesel-electric
Top speed117 mph
Starting effort51,000 lbf
EngineALCO 244
Engine typeV16 diesel
Fuel1,000 us gal (diesel)
Engine output2,000 hp (1,491 kW)2,250 hp (1,678 kW)
Power Plant
Calculated Values
diesel locomotive
last changed: 05/2023

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