The design was started in 1959 for a four-seat cabin monoplane aircraft with a high wing and fixed undercarriage. The prototype, designated the Neiva Regente 360C, was first flown on 7 September 1961 with a 145 hp (108 kW) Continental O-300 piston engine.
The type was ordered into production by the Brazilian Air Force with a more powerful 180 hp (134 kW) Lycoming O-360-A1D engine. Eighty aircraft were built originally designated the U-42 (later changed to C-42) for the utility role. First delivery occurred in February 1975.[1] Neiva developed a three-seat air observation post version for the Air Force, designated the Regente 420L. Its tailcone was lowered in order to improve visibility, and it used a more powerful Continental IO-360D 210 hp engine. The aircraft was first flown in January 1967 as the YL-42. Forty were built for the Brazilian Air Force as the L-42. It had provision to carry light bombs or rockets on underwing hardpoints.
Neiva also developed a four-seat civil version designated the Lanceiro. The prototype (Registered PP-ZAH) first flew in 1970, followed by production aircraft in 1973. The company's subsequent involvement with Embraer resulted in the Lanceiro's program termination.