During the 1970s the Brazilian Air Force operated over 100 piston-powered Neiva Universal basic trainers. Encouraged to undertake a follow-on project known as "Universal II", Indústria Aeronáutica Neiva rolled out the prototype N621A (YT-25A) in 1975 with an extended body, four hard points, and the more powerful 400 hp Lycoming IO-720-A1A engine which drove a three-bladed Hartzell propeller. The YT-25B prototype, a further modified version with six hard points, flew on 22 October 1978, but it did not meet requirements since the type was slower and smaller, and had side-by-side seats and a rear jump seat. Two years later, the company was acquired by Embraer. In 1973, designer Joseph Kovács moved from Neiva to Embraer, bringing with him a number of studies based on the Neiva Universal, including a development of the tandem-seat, turboprop Carajá.