Eurocopter AS355 Écureuil 2

AS355 Écureuil 2/Twin Squirrel/TwinStar
File:File:Aérospatiale AS-355 F2 Ecureuil 2 Héli Béarn SARL F-HJLD - MSN 5064 (5387445580).jpg
An AS355 departs Toulouse–Blagnac Airport
Role	Light utility helicopter
National origin	France
Manufacturer	Aérospatiale Eurocopter Airbus Helicopters
First flight	28 September 1979
Status	In service
Produced	1975-present
Developed from	Eurocopter AS350 Écureuil
Developed into	Eurocopter AS555 Fennec 2

The Eurocopter (now Airbus Helicopters) AS355 Écureuil 2 (or Twin Squirrel) is a twin-engine light utility helicopter originally manufactured by Aérospatiale in France (later part of Eurocopter Group, now Airbus Helicopters). The AS355 is marketed in North America as the TwinStar.

Design and development

Development at Aérospatiale began in the early 1970s to replace the Aérospatiale Alouette II, and the first flight took place on 27 June 1974. A twin-engined version, known as the Écureuil 2, Twin Squirrel, or in North America as the TwinStar, first flew on 28 September 1979. Despite the introduction of the Eurocopter EC130 in 2001, production of both the AS350 and AS355, and of their AS550 and AS555 Fennec militarized counterparts, was continued for some time. In 2007, the more capable AS355 NP variant with FADEC engines was introduced to service. In September 2015, Airbus Helicopters announced that it was to terminate the manufacture of the AS355 as part of an effort to focus on stronger-selling rotorcraft – production of the AS350 is to continue. Production of the AS355 is to continue through 2016 until the existing order backlog is fulfilled.

Variants

Twin engine

AS355N Twin Squirrel

Royal Malaysian Police Air Wing's Twin Squirrel.

AS355 Ecureuil 2

BBC News AS355 G-TVHD

AS355

Prototype of the twin-engined Écureuil 2 or Twin Squirrel.

AS355 E

Initial production version, with single hydraulics, powered by two Allison 250-C20F turboshaft engines.

AS355 F

Improved version, with dual hydraulics and increased maximum weight of 2,300 kg (5,070 lb).

AS355 F1

Powered by two Allison 250-C20F engines, 2,400 kg (5,291 lb) Maximum weight.

AS355 F2

Powered by two Allison 250-C20F engines, 2,540 kg (5,600 lb) Maximum weight and a yaw compensation system.

AS355 M

Initial armed version of AS355 F1.

AS355 M2

Armed version of AS355 F2. Superseded by AS555 Fennec.

AS355 N Ecureuil 2

Version fitted with two Turbomeca Arrius 1A engines and a Full Authority Digital Engine Control (FADEC) system for better M.T.O.W (2,600 kg or 5,732 lb) and better single engine performance, tail rotor strake added along starboard side of tail boom for better yaw authority.

AS355 NP Ecureuil 2

Introduced in 2007, this version is fitted with two Turbomeca Arrius 1A1 turboshaft engines and a new AS350 B3-based main gearbox, increasing maximum take-off weight to 2,800 kg (6,173 lb).

HB.355F Esquilo Bi

Assembled in Brazil by Helibras (part of Eurocopter).

HB.355N Esquilo Bi

Assembled in Brazil by Helibras.

Aftermarket conversions

Heli-Lynx 355FX1

Powered by the Allison C20F engine. FAA, TC, and EASA approved.

Heli-Lynx 355FX2

Powered by the Allison C20F engine. FAA,TC and EASA approved.

Heli-Lynx 355FX2R

Powered by the Allison C20R engine. FAA and TC approved.

Starflex AS355F1R

AS355 F1 powered by the Allison C20R engine. FAA, TC and EASA approved.

Starflex AS355F2R

AS355 F2 Powered by the Allison C20R engine with optimised tail rotor blades. FAA, TC and EASA approved.

Operators

The AS355 Écureuil 2 is used by both private individuals and companies, helicopter charter and training organizations as well as law enforcement and government use.

Military and government operators

Algeria

• Algerian Air Force

Argentina

• Argentine Naval Prefecture

Belarus

• Border Guard

Brazil

• Brazilian Air Force
• Brazilian Navy

Cambodia

• Royal Cambodian Air Force

Canada

• Ontario Provincial Police

Djibouti

• Djibouti Air Force

Jamaica

• Jamaica Defence Force

Malawi

• Malawi Air Wing

Malaysia

• Royal Malaysia Police

West Midlands Police's G-WMPA

New Zealand

• New Zealand Police

Russia

• Ministry of Interior

Uruguay

• National Navy of Uruguay

United States

• Massachusetts State Police

Former operators

Bophuthatswana

• Bophuthatswana Air Force

Ireland

• Garda Air Support Unit

Accidents and incidents

• On 22 October 1996, Chelsea Football Club Vice chairman Matthew Harding together with five companions were killed when their AS355 F1 Squirrel, registration G-CFLT, crashed near Middlewich, Cheshire.
• In July 1998, the Kent Air Ambulance, a AS355 F1 Squirrel, crashed in good weather after colliding with power cables near Burham whilst returning to Rochester Airport following an aborted call to attend a road accident. All three crew – the pilot, Graham Budden, and two paramedics, Tony Richardson and Mark Darby – were killed on impact.
• In May 2007, Chelsea Football Club Vice President Philip Carter, founder of training company Carter and Carter, crashed in his part-owned Twin Squirrel registration G-BYPA returning from Liverpool John Lennon Airport after watching Chelsea play Liverpool F.C.

VH-NTV in December 2010

• On 18 August 2011, a AS-355F-2 (reg No/ VH-NTV) crashed near Lake Eyre in South Australia resulting in three fatalities. The helicopter was owned by the Australian Broadcasting Corporation. On board were, Gary Ticehurst (ABC chief helicopter pilot for 25 years), John Bean (cameraman) and Paul Lockyer (journalist). All three had 20 years or more experience working for the ABC.
• On 20 October 2011, a Belarus border patrol Eurocopter twin-engine helicopter crashed close to the village of Vileity near the Lithuanian border and burst into flames, killing all five people on board, including three members of a television crew.
• On 29 March 2017, a Eurocopter AS-355F-1 Ecureuil 2 was lost over the Snowdonia National Park in Wales whilst en route from Luton to Dublin, carrying five people on board.

Specifications (AS355F2)

Cockpit of AS355 F1 Ecureuil 2

Data from Jane's All The World's Aircraft 1988–89

General characteristics

• Crew: 1
• Capacity: 6
• Length: 12.94 m (42 ft 5½ in)
• Rotor diameter: 10.69 m (35 ft 0¾ in)
• Height: 3.14 m (10 ft 3½ in)
• Disc area: 89.75 m² (966 sq ft)
• Empty weight: 1,305 kg (2,877 lbs)
• Max. takeoff weight: 2,540 kg (5,732 lbs)
• Powerplant: 2 × Allison 250-C20F turboshaft, 313 kW (420 shp) each

Performance

• Never exceed speed: 278 km/h (150 knots, 172 mph)
• Cruise speed: 224 km/h (121 knots, 139 mph)
• Range: 703 km (380 nm, 437 mi)
• Service ceiling: 3,400 m (11,150 ft)
• Rate of climb: 6.5 m/s (1,280 ft/min)

See also

• Eurocopter AS350
• Eurocopter AS555 Fennec
• Eurocopter EC130
• Bell 427
• MD Helicopters MD Explorer
• List of active United Kingdom military aircraft

References

Bibliography

• Taylor, John W.R. Jane's All the World's Aircraft 1988–89. Coulsdon, UK:Jane's Defence Data, 1988. ISBN 0-7106-0867-5.
• Directory: World Air Forces. Flight International, 11–17 November 2008. pp. 52–76.

External links

• AS355 page on manufacturer’s website