The Eurocopter AS350 Ecureuil (├»┬┐┬ŻSquirrel├»┬┐┬Ż) and AS355 Ecureuil 2 are a family of light helicopters originally manufactured by Aérospatiale (now part of Eurocopter Group). The AS350 (marketed as the AStar in North America) is the single-engined version, while the AS355 (TwinStar) uses two engines. The EC130B is a recent adaptation of the AS350 airframe.
Development began in the early 1970├»┬┐┬Żs to replace the Alouette II, and the first flight took place on 27 June 1974.  A twin-engined version, known as the Ecureuil 2, Twin Squirrel, or in North America as the TwinStar, first flew on 3 October 1979. Despite the introduction of the EC130, production of the Eurocopter AS350 and AS355, and the AS550 and AS555 Fennec military versions remains strong.
Both single and twin-engined versions have been built under licence by Helibras in Brazil.
Fire fighting version.
Powered by one Turbomeca Arriel 1B engine.
Powered by one Turbomeca Arriel 1D engine.
Higher gross weight version powered by one Turbomeca Arriel 1D1 engine.
High-performance version, is powered by a Turbomeca Arriel 2B engine equipped with a Full Authority Digital Engine Control (FADEC) system. This helicopter is the first ever to land on Mount Everest. Recently introduced AS350 B3/2B1 variant introduces enhanced engine with dual digital FADEC, dual hydraulics and a 2,370 kg (5,225 lb) M.T.O.W.
Powered by a Turbomeca Arriel 1B engine and fitted with wider chord main rotor blades.
AS350 B2 variant selected to meet rotary-wing training needs of UK MoD, through its Defence Helicopter Flying School in 1996. Powered by a derated Turbomeca Arriel 1D1 engine to improve the helicopters├»┬┐┬Ż life cycle.
Eurocopter Squirrel HT.1
Designation of AS350BB in operation with British RAF as a training helicopter.
Eurocopter Squirrel HT.2
Designation of AS350BB in operation with British Army Air Corps as a training helicopter.
Initial variant of Lycoming LTS-101-600A2 powered version developed for the North American market as the AStar. Quickly superseded by AS350D.
Powered by one Lycoming LTS-101 engine for the North American market as the AStar. At one stage marketed as AStar ├»┬┐┬ŻMark III.├»┬┐┬Ż
Military derivative of AS350 B1, powered by a 510-kW (684-shp) Turbomeca Arriel 1D turboshaft engine. Superseded by AS350 L2.
Military derivative of AS350 B2, powered by a 546-kW (732-shp) Turbomeca Arriel 1D1 turboshaft engine. Designation superseded by AS550 C2.
HB350 B Esquilo
Unarmed military version for the Brazilian Air Force. Brazilian designations CH-50 and TH-50. Built under licence by Helibras in Brazil.
HB350 B1 Esquilo
Unarmed military version for the Brazilian Navy. Brazilian designation UH-12. Built under licence by Helibras in Brazil.
Armed military version for the Brazilian Army. Brazilian designation HA-1. Built under licence by Helibras in Brazil.
Soloy Super D
AS350 BA powered by an LTS101-600A-3A engine.
Soloy Super D2
AS350 B2 powered by an LTS101-700D-2 engine.
AS350 BA powered by an LTS101-600A-3A engine.
AS350 BA or AS350 B2 powered by an LTS101-700D-2 engine.
AS350 BA powered by an LTS101-600A-3A engine .
Royal Australian Air Force - former operator
No. 5 Squadron RAAF
Australian Army Aviation - former operator
Fleet Air Arm (RAN)
No. 723 Squadron RAN
Chilean Army AS350
Ministry of Defence├»┬┐┬Żs Defence Helicopter Flying School at RAF Shawbury - 38 AS350 BB helicopters in service with FB Heliservices for the for training all British Armed Forces helicopter pilots.
Law Enforcement operators
San Bernardino County Sheriff├»┬┐┬Żs AS350 B3 Austria
Flugpolizei (Ministry of Interior) operates five AS350 B1
South African Police Service Air Wing operates 11 AS350B3s.
Anaheim Police Department operates an AS350 B2 helicopter.
Baltimore County Police Department recently[when?] purchased three Eurocopter AS350B3 helicopters.
Bernalillo County(Albuquerque, New Mexico) Sheriff Department operates an AS350 B3 helicopter.
Broward County Sheriff├»┬┐┬Żs Office operates an AS350 B2 helicopter.
California Highway Patrol operate 10 AS350 B3 helicopters and a single AS350 B2.
Citrus County Sheriff├»┬┐┬Żs Office(Florida) operates a single AS350 B3 helicopter.
Dekalb County Police (Georgia) operate 2 AS350 B2 helicopters.
East Bay Regional Park Police(Oakland, California) operates an AS350 B2 helicopter.
Hillsborough County Sheriff├»┬┐┬Żs Office(Florida) operates 3 AS350 B2 helicopters.
Lee County Sheriff├»┬┐┬Żs Office(Florida) operates two AS350B/B2 helicopters.
Los Angeles Police Department operates 14 AS350 B2 helicopters.
Los Angeles County Sheriff├»┬┐┬Żs Department operates 12 AS350 B2 helicopters.
Massachusetts State Police operates an AS350 BA.
Memphis Police Department operates an AS350 B3 helicopter.
Oakland County Sheriff├»┬┐┬Żs Department operates 2 AS350 B2 helicopters.
Ohio State Highway Patrol operates an AS350 B2 helicopter.
Ontario, CA Police Department operates 2 AS350 B2 helicopters.
Orange County, CA Sheriff├»┬┐┬Żs Department operates 2 AS350 B2 helicopters.
Phoenix Police Department operates 3 AS350 B3 helicopters.
Pinellas County Sheriff├»┬┐┬Żs Office (Florida) operates 2 AS350 B2 helicopters.
Riverside County Sheriff├»┬┐┬Żs Department operate 4 AS350 B3 helicopters.
San Antonio Police Department operates an AS350 B3 helicopter.
San Bernardino County Sheriff├»┬┐┬Żs Department operates 6 AS350 B3 helicopters
San Diego Police Department operates 4 AS350 B3 helicopters.
Suffolk County Police Department(Long Island, New York) operates 2 Eurocopter AS350 B2 helicopters.
Texas Department of Public Safety operates three AS350 B and nine AS350 B2 helicopters.
U.S. Customs and Border Protection operates 48 AS350 helicopters, and in July 2008 signed a multi-year contract for up to 50 additional AS350 B3s to meet its Light Enforcement Helicopter requirement.
U.S. Immigration and Customs Enforcement operate several AS350 B2 and AS350 B3 helicopters.
U.S. Drug Enforcement Agency operates two AS350 B2 helicopters.
Utah Highway Patrol operates 2 AS350 B2 helicopters.
Washington DC Metro Police Department operates 2 AS350 B3 helicopters.
Two AS350 helicopters operated by Sokha Helicopters at Angkor Wat, Siem Reap, Cambodia
AS350 B3 heli-ski helicopter operated by Jet Systems at Les Arcs
AS350 B2 operated by Heliflite
Wucher Helicopter operates the AS350 B3.
Australian Antarctic Division - uses the Eurocopter AS350 for intra-continental air operations in Antarctica.
Helicopters.cl (AS350 B3)
Kipreos (AS350 BA)
SumaAir (AS350 B3)
Heliflite Oy in the arctic Finland
3 AS350 B in service with Hungarian Air Ambulance Service, all of them received general overhaul in 2005-2007.
1 AS350 B2 is operated by Northflight, also do they have one more on its way.
Fireman Helicopters Group, Autonomous Province of Trento  utilizes two AS350 B3 for mountain rescue, fire service, transport service and various civil defence activities.