The Aerospatiale Ecureuil was designed for the civil market, the prototype (F-WVKH) being flown for the first time on 27 June 1974 with a Lycoming LTS 101 turboshaft, being followed by the second prototype (F-WVKI) with a Turbomeca Arriel 1A engine.

The prototype of the Ecureuil (Squirrel) light utility helicopter, powered by a Lycoming LTS 101 turboshaft, was flown for the first time on 27 June 1974. On 14 February 1975, the second prototype was flown, powered by the French Arriel turboshaft. The type subsequently entered production France at an initial

The AS 355 was a development of the AS 350 series with twin engines aimed at the police, ambulance, EMS and media role seating six persons, and more than 650 examples have been produced.