X1, X1A1 Carcara and X1A2 Light Tank

Bernardini S/A Industria e Comercio (Bernardini Industrial and Commerce Company) of Sao Paulo, Brazil, which operated from 1912 to 1992, was originally a safe manufacturer. During its later years it branched out into vehicle production, with products including the M41B and M41C Light Tanks upgrades from the American M41, and the X1, X1A1 and X1A2 Light Tank rebuilds of the American M3, the MB-3 Tamoyo tank and the Xingu BT25 and BT50 wheeled vehicles.

At least 20 American M3 Stuart Light Tanks (out of a promised 65) were received in 1942 and used to replace armor then available in Brazil. A further 200 were acquired between 1944 and 1945, both in the M3 and M3A1 versions. By the 1970's it was becoming increasingly difficult to find spare parts for these tanks, so a decision was made to modernize part of the M3A1 series. The decision to modernize vehicles so old was a political one: by 1977 Brazil had denounced the US-Brazilian military agreements, so no more obsolete (and cheap) vehicles were available from North American sources.

In the early 1970s Bernardini rebuilt two American M3A1 Stuart light tanks for the Brazilian Army. Technical control of the project was under the direction of the Brazilian Army Research and Development Centre. The modifications included replacing the armor above the tracks by new sloped armor provided by the Biselli company, replacement of the original American gasoline engine with a six-cylinder Saab-Scania diesel developing 280 bhp, new volute suspension designed by the Novatracao company, new turret with a French DEFA D-921A 90 F1 90mm gun as fitted to the Panhard AML (4�4) and other light AFVs, and a fire-control system designed by the D F Vasconcelos Company. The vehicles weighed 15,000 kg, had a road range of 450 km and could ford to a depth of 1 meter without preparation.

Following prototype trials, the Brazilian Army ordered 100 M3A1 light tanks to be rebuilt to the new standard. The first 80 vehicles were modernized between 1975 and 1978. These were delivered to Cavalry Regiments under the designation X1, with final deliveries made in 1978. The new car, known as CC MB1 (Combat Car, Brazilian Model nr. 1) or X1A, remained in service until the 1990's.

The X1 was followed by the Carcara, or X1A1. This is essentially a stretched X1 with an additional volute spring suspension group, and three bogies (instead of two) on each side. The engine and turret were the same as fitted to the earlier X1 tank. Trials with the X1A1 were completed in 1977-78 but the Brazilian Army did not place an order for the vehicle and it didn't reach production.

Further development resulted in the CC MB2 X1A2 which was based on a new chassis rather than a rebuild of an M3A1 chassis. The X1A2 was offered for export. Based on the X1A1, this version retained very little of the original Stuart as even its hull was redesigned. The vehicle weighed 19 tons, had a crew of 3, was armed with a 90-mm gun and was powered by a Saab-Scania 300 hp diesel engine. A total of 30 vehicles - completely new ones, not modernized Stuarts - were produced in 1979-1983.

All had been withdrawn from Brazilian service by the end of the 1990s.