Eurocopter ancestor Aerospatiale undertook development of the AS350 Ecureuil, or Squirrel, as a successor to the Alouette light helicopter built by it and its own predecessor, Sud Aviation.
The emphasis of the design effort was on an aircraft with low operating and maintenance costs, low noise emissions, and low vibration. That effort got under way in the early 1970s, and the AS350 prototype first flew on June 22, 1974, powered by an Avco Lycoming LTS101 turboshaft engine. A second prototype, powered by a Turbomeca Arriel turboshaft, took to the sky on Feb. 14, 1975.
Deliveries of the Arriel-powered AS350B began in March 1978, five months after its certification by the French DGAC. The Lycoming-powered aircraft was sold in North America; it gained FAA certification on Dec. 21, 1977, and deliveries began in April 1978.
The aircraft’s versatility, costs, and performance made it an appealing product for a wide variety of missions. According to Xavier de la Servette, who manages light helicopter programs for Eurocopter, roughly half the Ecureuils in service are used for some form of utility mission, including firefighting, emergency medical services, and aerial work. About 25 percent of those in service fly in passenger transport or corporate/VIP service, he said, and 25 percent fly with para-public operations.
In addition to the civil applications, the aircraft has seen service with various military services. In its military utility or armed version, it is designated the AS550 Fennec.
Eurocopter has built and delivered Ecureuil variants for nearly 30 years. More than 4,000 members of the AS350 have been delivered worldwide. That type has accumulated about 43 million flight hours. The aircraft today accumulates about 1.15 million flight hours a year.
De la Servette said the fleet leader of the Ecureuil family has accumulated 25,500 flight hours and is in service with an air tour operator in Hawaii.