PA Specifications
Locomotive type |
Diesel-Electric |
Power source: |
Alco 244 16 cylinder |
Power |
2,000 hp |
Max. speed |
102 mph
(164 km/h) |
Gear ratio |
64:19 |
Alternator
(rectified output) |
AR10 |
Traction motors: |
Four model D77 DC, series wound, axle-hung |
Max. continuous tractive effort |
33,000 lb (23,586.8 kg) |
Wheel configuration |
Eight 40-in (15.75 cm), tapered tread in B-B configuration (two sets of two driven axles) |
Height |
14 ft. 11 in. (4.7 m) |
Weight |
156.1 U.S. tons (141.5 metric tons) |
Length |
65 ft. 8 in. (18 m) |
Width |
10 ft. 6 in. (3.1 m) |
|
The Alco PA series (Alco is short for American Locomotive Company) has often been regarded as the most beautiful and aesthetically pleasing diesel locomotive model ever built, even going so far as being designated an honorary steam locomotive!
Southern Pacific PA / PB
ALCO's beautiful PA-1 was ALCO's entry into the passenger train diesel craze in 1946, competing directly with the E-Units from EMD.
The first PA1 celebrated Alco's 75,000th loco to roll out of the erecting shop.
This attractive 2000HP loco was their high-speed passenger diesel.
Having more horsepower than their leading competitor, Alco felt that they had a fleet-ready competitive product.
PA1's were sleek, stylish, powerful, and were very well suited for America's passenger and fast freight trains. Additionally, their 65'8" bodies became excellent billboard advertising for the railroads that they served with pride.
The new unit were built with a single model 12-244 engine rated at 200HP and were carried on two A1A-A1A trucks.
The passenger units were built in two configurations: the Cab unit ( PA-1 ) and a booster ( PB-1).
In 1952 the model was again changed to PA-3 and PB-3. The change included external modifications, removal of a porthole behind the radiator shutters, and replacement of the original side grills with Farr grills, removed the unique piece behind the cab and made the models easy to spot.
However, the PAs were offset by serious problems in the 244 engine. The PAs frequently broke down due a variety of reasons, and by the 1950s, railroads were pulling their PAs from their priority passenger trains.
Southern Pacific owned the most of units with 64.
Originally run on the Texas and New Orleans, Southern Pacific PA's #6055 and 6056 were later put into service on the SP's coastal division, pulling trains such as the Morning Daylight.
Most PA’s were out of service by the mid-1960’s, but is significant that the last operators were ATSF and SP. |