Program Updates: Twin-engine Helicopters

 - February 19, 2010, 5:22 AM

AgustaWestland has begun delivering a tailored version of the AW109S Grand to Swiss air rescue organization Rega. The Da Vinci, the result of a set of specifications issued by Rega to replace its A109 K2s, is thus not offered to other customers.

The cockpit is new and includes a dual duplex four-axis digital automatic flight control system, a 3-D synthetic vision and terrain awareness and warning system (Taws), a Euronav V digital map and a Max-Viz EVS-1000 enhanced vision system (EVS). The cockpit is equipped for single-pilot VFR operations and is compatible with night-vision goggles.

The Da Vinci delivers more power through the main transmission with one engine out and has an aerodynamically cleaner rotor system. This contributes to an increased rate of climb and more speed, both of which are important for Rega’s operations in the Alps. Rega and Aerolite developed a special EMS interior.

Thanks to its fixed landing gear, the aircraft is thought to be more than 200 pounds lighter than the standard Grand, but AgustaWestland would not confirm this.

The twin-engine Bell 429, an FAR Part 27 light helicopter, received its Transport Canada certification and FAA validation in July last year, giving it the distinction of being the only helicopter worldwide to obtain certification in 2009. Although it shares some parts, components and systems with earlier Bells, the 429 is different enough to require a new certification, instead of being grandfathered on an older one. When Bell announced the 429 at Heli-Expo’05, the company estimated Transport & Canada and FAA approvals in the first quarter of 2007.

The Pratt & Whitney Canada PW207D1/D2-powered Bell 429 features a new main gearbox with run-dry capability; a four-blade, rigid, composite main rotor; composite tail rotor; dual hydraulics; three-axis autopilot; Rogerson Kratos flat-panel flight displays; and two Garmin GNS 430s with WAAS capability. The model’s mtow is 7,000 pounds, its max speed 155 knots and its endurance with IFR reserve 2.26 hours.

At the time of certification, Bell reported letters of intent (LOIs) for 301 aircraft. The company continues to convert these LOIs to purchase agreements, and has not yet announced the number converted. Several LOIs are known to be unconverted, however, including all but the first one (delivered last August) of launch customer Air Methods. Of the original 301 LOIs, 71 aircraft were tagged for air medical operations, 49 for utility/offshore, 17 for law enforcement and the rest as corporate, other or unspecified. The current list price of the Model 429 is $4.865 million (2007 $).

Eurocopter’s EC175 medium twin made its first flight on Dec. 4, 2009. It is targeted at the offshore oil and gas market, which accounts for most of the 114 helicopters currently on order. EASA certification is pegged for the second half of next year, with first delivery planned for the second half of 2012. The lag between certification and delivery stems from the high number of options (40 to 45)–each of which needs to be certified–on this first aircraft, according to Eurocopter.

The cruise speed is understood to be approximately 140 knots. The radius of action offshore at ISA+20, with 16 passengers, will be 270 nm. Maximum range, with “very few” passengers, will be 700 nm. The EC175 is a seven-metric-ton-class (15,000-pound-class) helicopter. Two Pratt & Whitney Canada PT6C-67E turboshafts will supply 1,775 shp each.

The EC175 is a 50-50 joint program with China’s Avicopter, which calls it the Z15. Avicopter is responsible for the airframe, including flight controls. It is also developing the tail-rotor transmission and the fuel system and is responsible for some equipment integration–the landing gear and the engine. Finally, Avicopter builds the main rotor. Eurocopter’s share consists of the main gearbox, the tail rotor, doors, electric systems and the avionics suite, including autopilot.

The two firms have invested a total $600 million in a “common standard vehicle.” From there, they will offer two different sets of options and the helicopter will undergo two different certification processes through the EASA and the CAAC.

The Dhruv advanced light helicopter (ALH) by India’s state-owned aeronautical and defense company Hindustan Aeronautics (HAL) is a multi-role, multi-mission helicopter in the 5.5-ton weight class. It is powered by two 990-shp Turbomeca TM333-2B2 turboshafts that have sufficient margins to provide single-engine performance and Category A takeoff and landing capability.

The Dhruv is two-thirds composite by weight for resistance to corrosion, longer life, ease of repair and crashworthiness.

The helicopter is designed to meet the requirements of both civil and military operators.

Company sources told AIN that HAL is able to offer any variant of Dhruv for civil use, and it builds these commercial helicopters to order. HAL has so far delivered 90 utility versions of the ALH to defense forces and civilian agencies. Prices vary according to modifications.

The current production rate of the Dhruv is between 20 and 24 per year. The company intends to obtain EASA certification for the Dhruv. A new version with a glass cockpit and more powerful engines has already been certified by the DGCA.

Russian Helicopters is flight testing a Kamov Ka-226 light twin powered by Turbomeca Arrius 2Gs. Known as the Ka-226T, it is the first coaxial-rotor helicopter to be fitted with Turbomeca turboshafts, which raise its operating ceiling to 24,600 feet. Production is expected to start next year. The manufacturer is touting the performance of the Ka-226T “in mountainous terrain and hot climates, over water, in windy conditions and in urban high-rise operations.” The Ka-226T has an mtow of 8,800 pounds and a payload of 3,200 pounds. It can carry nine people, including two pilots. Maximum speed is 124 knots. With 10-minute emergency reserves, its range is 283 nm.

Instead of a conventional cabin, the Ka-226 can be outfitted with different cabin modules depending on the mission–passenger transport, patrol, construction, EMS, firefighting or search-and-rescue.

The latest variant of this now 34-year-old airframe was announced in 2005 and should  receive FAA certification in the first quarter of 2011. The S-76D first flew on February 7 last year. Currently three aircraft are in the flight-test program and the first production airframe was assembled in December at Aero Vodochody in the Czech Republic. The airframe will be shipped to Sikorsky-Coatesville in April for final assembly. Customer deliveries are slated to begin next year, and Sikorsky claims 100 “delivery position agreements” for the $12 million helicopter. Falcon Air Services of Abu Dhabi will be the launch customer for the S-76D.

While the S-76 airframe remains largely unchanged, the -D has significant upgrades in rotors, engines, avionics and cabin comfort. It features new composite, flaw-tolerant main rotor blades and electric rotorcraft icing protection, dual speed main rotor with active vibration control and quiet mode, a marginally quieter tail rotor, a health and usage monitoring system, digital four-axis autopilot and a glass cockpit that includes integrated digital maps. The -D will be powered by two Fadec Pratt & Whitney Canada PW210S engines, each producing 1,050 shp.

The modular PW210S promises to simplify maintenance as it has just five major rotating components and a combination reduction and engine accessory gearbox. The new engine/composite main rotor combination will give the S-76D up to 1,000 pounds more lifting capacity in hot and high conditions and increase range by 50 miles compared with the S-76C+.

The Thales TopDeck avionics suite developed for the -D features four six- by eight-inch LCD displays that provide flight, engine, caution and warning, systems status, checklists and mission data. The two outboard screens are PFDs and the inboards are MFDs. Data and symbology are automatically transferred to the MFD in the event of a PFD failure. The displays are NVG compatible. The jet-style trackball cursor control device allows control of avionics via virtual control panels on the cockpit displays and interfaces with the FMS through the cockpit displayed map, rather than the conventional keyboard.

The -D will incorporate the same Silencer noise-dampening cabin architecture used on the -C++. Two main executive layouts will be available for five to six passengers as well as a utility configuration that can accommodate up to 12.

Israel-based Urban Aeronautics is flying its Turbomeca Arriel 1D1-powered Mule UAV. As of mid-December, the company had performed only low hovers with safety wires, according to company CEO Rafi Yoeli. The AirMule is the demonstrator for Urban Aero’s concept of an aircraft featuring two shrouded main rotors in tandem configuration.

The company is eyeing a full-size, 11-passenger version–the X-Hawk. On the demonstrator, each of the two six-foot-diameter lift rotors has five blades. The two rotors are located fore and aft of the cabin. Two smaller shrouded rotors act as thrusters. The architecture, with its shrouded rotors, enables the aircraft to fly in a city without the dangers usually associated with open rotors. Its main drawback is fuel burn, much higher than that of a helicopter.  

Anand and Madhura Katti contributed to this report.