HH-65 Dolphin

HH-65 Dolphin

The Eurocopter HH-65 Dolphin is a twin-engine search and rescue (SAR) helicopter in service with the US Coast Guard (USCG). It is primarily used as a short range recovery (SRR) aircraft. It is a US version of the French-built Eurocopter SA366 G Dauphin.

The USCG operates 102 Dolphins from the Atlantic and Pacific Oceans, Gulf of Mexico, Hawaii and the Great Lakes regions.

The helicopters can perform a range of missions including search and rescue, smuggling prevention, homeland security, military preparation, ice breaking, marine environmental protection and pollution control missions.

Normally deployed from shore, the helicopters can also be operated from medium and high endurance USCG Cutters and Polar Icebreakers.

HH-65 Dolphin development

The Dolphin was originally manufactured by the Aerospatiale Helicopter Corporation (now American Eurocopter) in Grand Prairie, Texas. The USCG selected the helicopter to replace its Sikorsky HH-52A Sea Guard helicopter and designated it as HH-65A.

“HH-65 is powered by digitally controlled Turbomeca Arriel 2C2CG engines.”

The maiden flight of HH-65A Dolphin was completed in July 1980. DGAC certification was awarded in July 1982. The first delivery was made to the USCG in November 1984.

In 2004, the USCG began the HH-65 conversion project to extend the service life of the helicopter until 2025. The project includes upgrades to 95 aircraft and acquisition of seven new helicopters.

The converted Dolphins are equipped with a modern, robust command, control, communications, intelligence, surveillance and reconnaissance suite and other new equipment. The upgraded HH-65s will be re-designated as Multi-Mission Cutter Helicopter (MCH).

HH-65 helicopter design

The HH-65 resembles the AS365 Dauphin, but incorporates new engines and modern avionics. The fuselage, rotor head and rotor blades are made of corrosion resistant, composite materials. A renowned feature of the HH-65 is its Fenestron tail rotor with 11 blades whirling within a circular housing positioned at the base of the tail fin.

The helicopter is certified for single-pilot instrument flight rules (IFR) operations. It is also the first helicopter certified with a four-axis autopilot, a unique ability that allows for steep approaches in zero-visibility conditions.

HH-65 variants

HH-65A was the initial USCG variant powered by two LTS101-750B-2 turboshafts, providing 547kW each.

The HH-65B is equipped with an upgraded avionics suite. The first HH-65B was rolled out from the post-depot maintenance facility in March 2001.

HH-65C is an improved version of HH-65A/B. It is fitted with new Arriel 2C2-CG engines, upgraded main and tail gearboxes, and a long-nose avionics compartment. The maximum take-off weight (MTOW) was increased to 4,300kg. It also received an expanded lateral flight envelope and vehicle and engine multi-function display. The first retrofit was completed in October 2004.

MH-65C Multi-Mission Cutter Helicopter (MCH) is a further advancement of the HH-65C. It comes with a new flight deck recovery system, transmission upgrades, a 10-blade low-noise tail rotor, a relocated avionics suite and digital autopilot equipment. The MTOW of MH-65C has been increased to 4,500kg.

MH-65D is fitted with an upgraded flight navigation system, digital global positioning system and inertial navigation systems.

Cockpit

The semi-glass cockpit can accommodate a crew of three including a pilot, a co-pilot and crewman / hoist operator. It features digital glass instruments similar to those found in the USCG’s upgraded MH-60T Jayhawk medium range recovery helicopters.

“The maiden flight of HH-65A Dolphin was completed in July 1980.”

The onboard NVG-compatible integrated flight management avionics suite incorporates two GPS-embedded CDU-900G control display units and two MFD-255 multifunction displays. The uninterrupted onboard communications are supported by dual UHF / VHF transceivers and single UHF / FM and HF systems, as well as a data link for automatic transmission of data.

Armament

The aircraft is armed with an M107-derived, 0.5 calibre, precision fire weapon and an M240B 7.62mm, general purpose machine gun.

Sensors / radars

The helicopter is equipped with enhanced radar and electro-optical / infrared sensors that provide common operational picture / maritime domain awareness data exchange capability.

Engines

HH-65 is powered by digitally controlled Turbomeca Arriel 2C2CG engines providing 40% more power than the initial LTS 101 engines.

Performance

HH-65 can fly at a maximum altitude of 15,000ft. It has a maximum speed of 165kt and a range of 356nm.

Variants

  • HH-65A: Initial USCG version, powered by two 734 shp (547 kW) LTS101-750B-2 turboshaft engines and with an 8,900 lb (4,000 kg) MTOW.
  • HH-65B: Avionics upgrade undertaken on a portion of the fleet. Retrofit included an NVG-compatible integrated flight management avionics suite consisting of two GPS-embedded CDU-900G control display units and two MFD-255 multifunction flat panel displays. The HH-65B upgrade was undertaken at the Coast Guard’s Aircraft Repair and Supply Center (ARSC) in Elizabeth City, NC, with the first aircraft rolling-off the post-depot maintenance (PDM) line in March 2001.
  • HH-65C: HH-65A/B upgraded with new 934 shp (696 kW) Arriel 2C2-CG engines that provide 40% more power and higher performance, plus an upgraded tail gearbox, long-nose avionics compartment, increased 9,480 lb (4,300 kg) MTOW, expanded lateral flight envelope and Vehicle and Engine Multifunction Display (VEMD) with First Limit Indicator (FLI). First retrofit completed in October 2004.
  • MH-65C: Initially intended only for use by the Multi-Mission Cutter Helicopter (MCH), a further enhancement of the HH-65C within the USCG’s Deepwater effort, includes the installation of a 10-blade low-noise Fenestron, relocated avionics, and an Airborne Use of Force (AUF) package (in common with that of the modernized HH-60T) which provides the capability to fire warning and disabling shots from the air. The MH-65C is used in AUF missions, such as the Helicopter Interdiction Tactical Squadron (HITRON) mission taken up by the MH-65C in early 2008. AUF aircraft are armed with the Barrett M107CQ 12.7 mm anti-materiel rifle and M240G 7.62 mm machine gun. The helicopter can also be used for counter terrorism.
  • MH-65D: MH-65C with an upgraded flight navigation system common to Department of Defense helicopters. The first production MH-65D was completed on 20 January 2011 and is fitted with a Honeywell HG7502 radar altimeter, two Honeywell H-764G EGI’s (embedded GPS/inertial navigation systems) and two control display units CDU-7000D from Rockwell Collins. 97 HH/MH-65Cs will be upgraded to MH-65D standard.
  • MH-65E: The MH-65E will incorporate upgrades that will modernize the cockpit by installing digital “glass” cockpit instruments, known as the Common Avionics Architecture System (CAAS), similar to those installed in the Coast Guard’s upgraded MH-60T Jayhawk Medium Range Recovery (MRR) helicopters. The Echo upgrade will also replace the legacy analog automatic flight control with a digital system, and installing a digital weather radar system. The MH-65E model is expected to begin to be delivered to the fleet in 2017.

Specifications

Crew 2 pilots and 2 crew
Capacity  
Length (rotors running)
11.6 m (38 ft 1 in)
Height 4 m (13 ft 1 in)
Main rotor diameter 11.9 m (39 ft 1 in)
Loaded weight  
Maximum weight 4,300 kg (9,480 lb)
Empty weight 3,128 kg (6,896 lb)
Maximum speed (Vne) 330 km/h (210 mph, 180 kn)
Cruising speed at sea level 240 km/h (150 mph, 130 kn)
Ascent speed at sea level 1,650 ft/min (8.38 m/s)
Ceiling in service 5,486 m (17,999 ft)
Passable distance at sea level with standard reserve 658 km (409 mi, 355 nmi)
Powerplant 2 × Turbomeca Arriel 2C2-CG turboshaft engines, 636 kW (853 hp) each
Armament – 1 x 7.62 mm M240 machine gun
– 1 x Barrett M107 0.50 in (12.70 mm) caliber precision rifle

Operators

Related Armament

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