Fiat-Materfer (Buenos Aires Underground)

Fiat-Materfer
Fiat-Materfer at Plaza de Mayo station on Line A
Manufacturer	Materfer
Built at	Córdoba, Argentina
Entered service	1980
Number in service	95 cars
Formation	5-6 cars per trainset
Operator(s)	Buenos Aires Underground
Line(s) served	(former)
Specifications
Car body construction	Stainless steel
Doors	4 per side
Track gauge	1,435 mm (4 ft 8 1⁄2 in)

The Fiat-Materfer Buenos Aires Underground rolling stock was built by the Argentine company Materfer - then a subsidiary of Fiat Ferroviaria - beginning in 1980 and continuing on through that decade. It was originally conceived to standardise the diverse of the Buenos Aires Underground with the use of one model throughout all the lines. However, with the economic and political turmoil faced in the country during and following the collapse of the National Reorganisation Process junta in 1983, its production ended up being far more limited. Today the cars serve as temporary stock for two lines, being phased out as newer models arrive from overseas.

By the late 1970s, the Buenos Aires Underground had a vast array of ageing rolling stock - given that the different lines were developed by different companies in different periods - and the need for standardisation was becoming apparent given the increased cost of dealing with so many different models. One challenge was the use of 1100v electrification on Line A (though it was converted to 1500v in 2013) and 1500v on other lines, but also the use of third rail on Line B while all others use overhead lines.

In 1978, Materfer presented a prototype vehicle which solved the issue of the different voltages by providing a model which could be easily switched between the two voltages, though Line B would remain an independent entity in the underground network. The trains were produced throughout the 1980s for use on Line E, however due to the economic problems in the country at the time, they never attained widespread use on the rest of the network since there was not the funding available to purchase new rolling stock for all the lines.

Over the years, the cars have seen cosmetic upgrades, as well as technical ones, such as the incorporation of Automatic Train Protection and ability to play pre-recorded messages through its speakers - which was unusually left out at the time of production. While the Fiat-Materfer trainsets briefly made up the entire rolling stock of Line E, today they find themselves on Line D and Line A as temporary rolling stock alongside newer trains while more new cars arrive. As the new rolling stock arrives for these lines, the Fiat-Materfer trains will be stored, then incorporated into Line E once again in time for its extension to Retiro station, though this has yet to be confirmed by SBASE or whether the purchase of new rolling stock for Line E would mean the complete retirement of the trains from service.