The AA class were a development of the A class, the main difference being the more powerful 645 engine in place of the 567 fitted to the earlier locos but the same electrical gear (traction motors and generator). Some subtle body differences between the class were evident too. The AA's were numbered following on from the the previous classes numbering. ARG sold the entire class off and exported them to FCAB Chile where they have been rebuilt and continue in service.
Drive Type: Diesel Electric - DC
Engine: EMD 12-645E
Generator: EMD D25
Traction Motors: EMD D29
Horse Power: 1,650hp
Weight: 91.5t
Max rated speed: 100km/h
Builders Model: G22C