AgustaWestland Apache - Design

Design

Several deviations were made to the standard Apache design used by the US and those exported to other countries. One major difference is the use of a pair of Rolls-Royce Turbomeca RTM322 01/12 engines, replacing the original General Electric T700-GE-701C engines. The Rolls-Royce engine produces 1,565 kW (2,100 hp) vs 1,410 kW (1,890 hp) for the GE T700C engine. Unlike many helicopters used by coalition forces in Afghanistan, the Apache required less modification to serve in the region due to special filters incorporated into the design. Another change is the folding blade mechanism to stow the helicopters in confined spaces; the rotor blades also have anti-ice protection to allow operations in Arctic environments.

There were changes made to the sensor and avionics outfitting the craft as well; connectivity with the BOWMAN secure communications system to interact with other British military units being a significant one. The SELEX (formerly BAE Systems Avionics) Helicopter Integrated Defensive Aids System (HIDAS) was also fitted. The HIDAS system was retrofitted onto the aircraft in mid-2004 just prior to entering service, along with several redesigned composite bodywork components. An eye-safe training laser to allow the Apache to function as a target designator was also installed.

Instead of the American Hydra 70 rocket pods, the Westland Apache can carry up to 76 CRV7 rockets. The CRV-7 uses a modular warhead: "a high explosive, semi-armour piercing warhead for attacks on unarmoured targets and a kinetic energy penetrator, which contains no explosive, for attacks on armoured targets". There used to be a third type of warhead: the Multi-Purpose Sub Munition (MPSM), which was a controversial weapon as it has been classified as a cluster bomb; each rocket contained nine M73 submunitions. In May 2008, several senior officers, such as General David Ramsbotham spoke out against British plans to keep the weapon. In the same month, Britain, as one of the 111 participating nations, agreed to ban cluster bombs on humanitarian grounds. Britain destroyed the last of its CRV-7 MPSMs in July 2009.

Like the US AH-64D Apache Longbows, the Apache AH Mk 1 carries a fire-control radar (FCR) and Radar Frequency Interferometer (RFI), providing an integrated surveillance and attack system. The 'Longbow’ radar is the bulbous unit over the rotor hub assembly; radar placement above the rotors allows the Apache to hover behind cover scanning for targets, with only the radar unit exposed. Additionally, the Longbow radar can monitor traffic in the Apache's airspace. The radar can also be used for surveillance and terrain profiling. A modem is interfaced into the Longbow radar and other sensor systems to relay information to other aircraft, this allows other Apaches to fire on targets identified by only a single helicopter.

AgustaWestland have since made several upgrades to Britain's Apache fleet. In May 2005, a $212 million contract was awarded to equip all 67 Mk1 helicopters with the Apache Arrowhead sensor system upgrade, to be completed by 2010. In 2009, it was announced that AgustaWestland was also integrating new external fuel tanks with ballistic protection. Some of the internal fuel tanks can be removed, WAH-64s in Afghanistan may have these removed to allow for extra ammunition for the cannon to be fitted. It has been suggested that advanced rotor blades and additional controls to improve the agility of the aircraft may be fitted in a mid-life update of the fleet.