Revolutionary designs are equipping the latest versions with swiftness and the range of fixed-wing aircraft

Only a handful of nations and international consortia are engaged in developing new designs or upgrades in the field of rotary wing aircraft. The trend, however, is not limited merely to upgrades but also encompasses revolutionary designs that equip the new machines with dual capability of vertical take-off and landing (VTOL) as well as swiftness and range of fixed-wing aircraft. Two key areas in which developments are concentrated relate to attack helicopters and multi-role rotary-wing aircraft along with some special applications, such as VIP and VVIP transportation.

Trend setters involved in the development of the rotary wing include Bell, Boeing and Sikorsky from the US, Eurocopter and AgustaWestland from Europe, and Russia. India has also been making a mark in this field with the Hindustan Aeronautics Limited’s (HAL) versions of the Advanced Light Helicopter (ALH), Dhruv. At the forefront of the attack helicopter variations are the Apache, Super Cobra, Tiger, Mi-35 and the indigenous Light Combat Helicopter. In the multi-role utility designs are the products from Bell, Boeing, Eurocopter, AgustaWestland, Mil Bureau and HAL.

V-22 Osprey
A multi-mission, military tilt-rotor aircraft, the V-22 Osprey has both VTOL and short take-off and landing (STOL) capabilities. It is designed to perform missions like a conventional helicopter with the long-range, high-speed cruise performance of a turboprop aircraft. The V-22 was developed by Bell Helicopter and is being manufactured in partnership with Boeing Rotorcraft Systems.

The Osprey is the world’s first fully operational tiltrotor aircraft, with one three-bladed proprotor, turboprop engine, and transmission nacelle mounted on each wingtip. For takeoffs and landings, it typically operates as a helicopter with the nacelles vertical (rotors horizontal). Once airborne, the nacelles rotate forward 90 deg in as little as 12 seconds, lunging the aircraft into forward flight, converting the V-22 to a fuel-efficient, higher-speed turboprop airplane. The Osprey can also be used in STOL mode by swinging the nacelles forward by up to 45 deg. For compact storage and transport, the V-22’s wing rotates to align, front-to-back, with the fuselage. The proprotors can also fold in a sequence in about 90 seconds.

Equipped with a glass cockpit which incorporates four Multi-functional Displays and one shared Central Display Unit, it allows the pilots of the Osprey a variety of images, including digimaps, FLIR imagery, primary flight instruments, system status and navigation (Tactical Air Navigation, VHF Omnidirectional Range, Instrument Landing System, Global Positioning System, Inertial Navigation System). Cockpit management system allows for a fully-coupled autopilot which can take the aircraft from forward flight into a 50-ft hover with no pilot interaction other than programming the system.

Ironing out the initial glitches in flight-testing programmes, this revolutionary aircraft was cleared for full-scale production three years ago. Its unique utility in the battle area and force-multiplication qualities have been fully acknowledged, considering the numbers ordered by the US armed forces. Planned production includes 360 for the Marine Corps, 48 for the navy and 50 for the USAF.

NH90 Helicopter
A medium transport/utility helicopter, NH90 is a highly successful product of NH Industries which entered a contract with NATO Helicopter Management Agency (NAHEMA), initially as a consortium of four participating nations, namely, France, Germany, Italy and the Netherlands, with Portugal joining in as the fifth partner in 2001. The NH90 has been developed into two main variants: the Tactical Transport Helicopter (TTH) and the NATO Frigate Helicopter (NFH). However, many of the customer countries have asked for special modifications. A large production order for about 300 helicopters by partner countries was soon followed by a series of orders from Europe, the Middle East and Australia. In 2007, Belgium became the sixth nation to join NAHEMA.

The primary role of the NFH version is autonomous antisubmarine warfare) and anti-surface unit warfare, mainly from naval ships. Additional roles include anti-air warfare support, vertical replenishment, search and rescue, and troop transport. The primary role of the TTH version, on the other hand, is transport of 20 troops or more than 2,500 kg of cargo and heliborne operations, besides search and rescue. It can quickly be adapted to MEDEVAC or CASEVAC missions by fitting up to 12 stretchers, special operations, electronic warfare, airborne command post, parachuting, VIP transport and flight training. The NH90, therefore, meets the stringiest test of versatility which has become a modern day requirement of any utility helicopter. The helicopter also has an impressive max speed of 300 km/h.

ALH Dhruv
Indigenous, Dhruv has passed the test for its versatility, albeit in the light weight (5.5-tonne) class and as a multi-role helicopter which has been successfully developed and manufactured by HAL. While the ALH is being supplied predominantly to the Indian armed forces (80 in service plus 235 on order), it has also attracted a large number of other customers both from within the country and also from abroad for military and commercial use. HAL plans to annually produce between 50 and 80 ALHs. One of only three helicopter display teams in the world, the Sarang aerobatic team of the Indian Air Force (IAF) performs with four Dhruv helicopters.

Fitted with the more powerful Shakti engines, Dhruv is capable of flying at high altitudes, a crucial requirement for the Indian armed forces. A Dhruv flew to an altitude of 27,500 ft above mean sea level in October 2007, bettering the record of 25,000 ft set by an IAF Cheetah helicopter in 2005. A Weapon System Integrated (WSI) Dhruv is under development for the Indian armed forces. It will have stub wings fitted to carry up to eight anti-armour missiles, four air-to-air missiles or four rocket pods of 68 mm and 70 mm rockets. The WSI variant will also be equipped with Forward Looking Infrared (FLIR), Charge Couple Device camera and a target acquisition system with thermal sight and laser rangefinder. In addition, Nexter Systems (formerly GIAT) has been contracted for the installation of THL 20, 20 mm gun turret which is armed with M621 lowrecoil cannon that combines with a helmet-mounted sight.