AS365 Dauphin

AS365 Dauphin

The Eurocopter (now Airbus HelicoptersAS365 Dauphin (Dolphin), also formerly known as the Aérospatiale SA365 Dauphin 2, is a medium-weight multipurpose twin-engine helicopter produced by Airbus Helicopters. It was originally developed and manufactured by French firm Aérospatiale, which was merged into the multinational Eurocopter company during the 1990s. Since entering production in 1975, the type has been in continuous production for more than 40 years. The intended successor to the Dauphin is the Airbus Helicopters H160, which is yet to enter operational service as of January 2020.

The Dauphin 2 shares many similarities with the Aérospatiale SA 360, a commercially unsuccessful single-engine helicopter; however the twin-engine Dauphin 2 did meet with customer demand and has been operated by a wide variety of civil and military operators. Since the type’s introduction in the 1970s, several major variations and specialised versions of the Dauphin 2 have been developed and entered production, including the military-oriented Eurocopter Panther, the air-sea rescue HH/MH-65 Dolphin, the Chinese-manufactured Harbin Z-9 and the modernised Eurocopter EC155.

Development

The SA 365/AS365 Dauphin 2 is a twin-engine development of the commercially unsuccessful single-engined Aérospatiale SA 360 Dauphin; only a year after the SA 360’s entry into service, Aerospatiale had recognized that a platform powered by two engines rather than one was better suited to both civil and military operations, thus a redesign program was initiated. In January 1975, the first twin-engine Dauphin prototype performed its first flight; the prototype soon demonstrated an airspeed of 170 knots in level flight and set multiple speed records, among them the Paris-London trip at an average of 322 km/h. Deliveries of production models began later that decade

The initial production variant entered service under the original designation of SA 365C; French certification of this model was received in July 1978. In 1982, the SA 356C Dauphin was succeeded by the more capable SA 365 N. Amongst several major design changes and improvements, the SA 365 N featured more powerful engines, greater use of composite materials, a better cabin arrangement, and retractable landing gear.

Further improvements were made with the introduction of the SA 365 N1, which had a substantially redesigned Fenestron anti-torque device, and with the SA 365 N2, which was equipped with more powerful Turbomeca Arriel 1C2 turboshaft engines. In January 1990, the overall type was formally redesignated as the AS365. The AS365 Dauphin is one of Eurocopter’s more successful helicopter designs; and has been widely used as a corporate transport, airborne law enforcement platform, emergency medical services (EMS) helicopter, electronic news gathering platform, and search & rescue helicopter.

The base Dauphin has been further developed into several purpose-built variants. During the 1980s, the SA 365 N was used as the basis for a militarised version of the Dauphin, initially designed as AS 365 K, which was used to perform utility, troop-transport, and maritime operations, widely known as the Eurocopter Panther. A variant of the Dauphin was specifically developed for and operated principally by the United States Coast Guard under the designation HH/MH-65 Dolphin. The SA 365 M model of the Dauphin has also been manufactured under licence in China as the Z-9 by the Harbin Aircraft Manufacturing Corporation; the Z-9 was subsequently developed into the armed WZ-9 and Z-19 attack helicopter.

Design

The AS365 Dauphin is a twin-engine helicopter capable of travelling long ranges, and well suited to operating in climates of a high ambient temperature or at locations of significant altitude. The Dauphin is typically powered by a pair of Turbomeca Arriel turboshaft engines; on later variants, these are equipped with FADEC units, which provide additional functionality such as an automated start-up sequence and a training mode. The engines drive the rotorcraft’s foldable Starflex main rotor and its Fenestron anti-torque tail rotor via two separate transmissions; these gearboxes are also connected to two separate hydraulic systems as well as a stand-by hydraulic system for emergency use, such as deployment of the landing gear. Electrical power is provided by a pair of starter generators and a NiCad (Nickel-Cadmium) main battery; an emergency battery is also present.

The main fuselage of the rotorcraft comprises the cabin area, a separate luggage compartment, and a retractable tricycle landing gear arrangement; a total of four conventional doors to access the main cabin are typically installed, which can be optionally replaced by a single clamshell air stair entrance instead. Various portions of the rotorcraft are made from composite materials, such as the rotor blades that made of carbon fiber, other materials are used in portions of the fuselage. The fuselage features anti-corrosion protection and is structurally reinforced for an optional hoist or cargo sling to be installed, various other mooring and gripping points are also fitted on the rotocraft’s exterior surface. Various types and models of radar can be installed in the Dauphin’s nose.

The combination of the rotorcraft’s Starflex main rotor and Fenestron tail provides a low-noise and low-vibration flight experience for those on board; Airbus Helicopters has claimed the sound emissions of the AS365 N3 to be 3.1 decibels below International Civil Aviation Organization (ICAO) standards, making it the quietest helicopter in its class. The Dauphin can take off under a full load from sea level under Category A conditions. The main cabin area is designed to be reconfigurable, a feature which is promoted to emergency medical service (EMS) and search and rescue (SAR) operators. In a regular passenger transport layout, the cabin can accommodate up to 12 passengers in addition to the two pilots; up to seven passengers can be accommodated in a VIP layout. Access to the cabin is via large sliding doors on either side of the helicopter, built-in boarding steps are typically installed to ease the boarding of passengers.

While the cockpit is typically equipped with dual flight controls for two-man operations, the Dauphin can be readily flown by a single pilot while operating under instrument flight rules; this was achieved in part by avionics such as the 4-axis Dual Digital Automatic Flight Control System (older production aircraft use a 3-axis flight control system with integrated autopilot instead) to reduce crew workload. The principal flight control system are connected to a total of 3 dual-chamber primary servo-units for cyclical and collective pitch control, and a single dual-chamber rear servo-unit for tail rotor pitch control. Other major avionics include 10.4-inch (26 cm) multi-mission touch screen displays, weather radar, global positioning system (GPS) receiver, traffic alert and collision avoidance system (TCAS), automatic voice alarm device (AVAD), health and usage monitoring system (HUMS), quick access records for helicopter flight data management, and digital audio communication system (DACS).

Variants

  • AS565 Panther
  • SA366 G1 Dauphin: The SA 366 G1 Dauphin version was selected by the US Coast Guard (USCG) in 1979 as its new air-sea rescue helicopter and given the designation HH-65A Dolphin. In total 99 helicopters, optimized for the USCG’s short-range recovery (SRR) search and rescue role, were initially acquired, with additional aircraft later procured.
  • SA365N Dauphin: A much improved version of the SA365C Dauphin 2, the first prototype flying on 31 March 1979. This version introduced the upgraded 492 kW (660 shp) Arriel 1C turbo-shafts, a retractable tricycle undercarriage, enlarged tail surfaces, and revised transmission, main rotor, rotor mast fairing and engine cowlings. The aircraft’s initial M.T.O.W. of 3,850 kg (8,490 lb) was later raised to 4,000 kg (8,800 lb). Deliveries of the production model began in 1982.
  • SA365F Dauphin: The SA365F is a variant of the SA365N for the French Navy. It has been used since 1991 for general duties and for backup purposes aboard an aircraft carrier. A helicopter with rescue divers is always in the air during flight operations to be able to assist the pilot in case of an accident. First experiments were successfully carried out in 1990 on board the French aircraft carrier Clemenceau. The variant 365F is used since 1999 with Flottille 35F called AS365F Dauphin Pedro.
  • AS365N3 Dauphin: The high-performance AS365 N3 was developed for operations in ‘hot and high’ climates, and introduced 635 kW (852 shp) Arriel 2C turbo-shafts equipped with a single channel DECU (Digital Engine Control Unit) with manual reversion, mated to an upgraded main transmission for better single engine performance. The AS365 N3 also features a redesigned ten blade composite Fenestron anti-torque device with asymmetric blade distribution, offering a further reduction in noise signature. The AS365 N3’s gross weight is 4,300 kg (9,500 lb). Production deliveries began in December 1998.
  • AS365 N3+: This version was presented by Eurocopter at the 2009 Paris Air Show and differs mainly in new avionics including 4-axis auto-pilot

Specifications

Crew 1 or 2 pilots
Capacity 11 or 12 passengers
Length (rotors running)
13.73 m (45 ft 1 in)
Height 4.06 m (13 ft 4 in)
Main rotor diameter 11.94 m (39 ft 2 in)
Loaded weight
Maximum weight 4,300 kg (9,480 lb)
Empty weight 2,389 kg (5,267 lb)
Maximum speed (Vne) 306 km/h (190 mph, 165 kn)
Cruising speed at sea level
Ascent speed at sea level 8.9 m/s (1,750 ft/min)
Ceiling in service 5,865 m (19,242 ft)
Passable distance at sea level with standard reserve 827 km (514 mi, 447 nmi)
Powerplant 2 × Turboméca Arriel 2C turboshaft, Take-off Power, 625 kW (838 hp) each

Operators

  • French Navy
  • UK Army – 5 AS365 Dauphin in active.
Related Armament

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