During the 1980s, there was considerable interest within French aerospace manufacturer Aerospatiale to further develop their successful AS350 B3 Écureuil rotorcraft, which had been originally developed in the early 1970s. On 6 February 1987, a prototype AS350 Z (a modified AS350 B2) conducted its first flight with a Fenestron tail-rotor fitted in the place of its conventional counterpart. The AS350 Z test program stretched across several years, the aircraft receiving additional modifications such as a new air intake based on that of the Eurocopter EC120. The AS350 Z contributed to the overall development of the fenestron tail rotor.