After all-jet training program trials during the 1950s, a variety of propeller-driven aircraft was used for pilot training during the 1960s and 1970s. In the 1970s, oil prices rapidly increased with the price of a crude oil barrel having risen from $3 in 1973 to $36 by 1980, deflating the Brazilian economy. At that time, the Brazilian Air Force operated the J69-powerered Cessna T-37C, which was a 1950s design and following the 1970s energy crisis, became expensive to operate. In 1977, the Brazilian Air Force expressed a desire to replace the T-37, specifying that the replacement would need to be cheap to operate, designed to closely imitate the characteristics of jet aircraft and should have ejection seats.