PAUL LEWIS / MESA

US Army envisages update of 232 rotorcraft as part of $1.3 billion modernisation

Greater detail is emerging about the proposed $1.3 billion Block 3 modernisation of the Boeing AH-64D Apache Longbow, with the US Army envisaging an iterative upgrade of 232 helicopters initially, over five annual purchases starting in 2008.

The notional upgrade plan, which is still subject to funding approval, would start in 2008 with the first AH-64s upgraded to Apache Longbows between 1997 and 2001, and would conclude in 2012. The main focus would be equipping the helicopter with the Joint Tactical Radio System cluster 1 and introducing an open-system architecture to ensure compatibility with the army's future structure.

Added capabilities would include control of unmanned air vehicle sensors with the addition of a mast-mounted steerable antenna on some helicopters in place of the Longbow fire control radar (FCR) and a plug-in modem. Other enhancements would include the Suite of Integrated Infrared (IR) Countermeasures, and a transportability kit, elements of which have already entered service to support Iraq war deployments, and which are not ready for production.

The follow-on production in 2009 would additionally introduce a new dual-mode training and targeting laser, embedded diagnostics, improved radio-frequency interferometer (RFI) with extended frequencies, global air traffic management compatibility and image fusion of the helicopter's forward-looking IR sensor, image intensified TV and target identification system.

A more reliable General Electric T700-701D turboshaft and Affordable Apache Drive system, with a more durable and uprated 3,400shp (2,530kW) gearbox, will be delivered in 2010. Boeing says there is still the option to switch to an in-development, more powerful 4,000shp split-face gearbox if there are programme delays. An FCR software upgrade will be implemented in 2011 to include classification of littoral targets, with a range extension in 2012.

The final production lot would also have cognitive decision-aiding developed under the Rotorcraft Pilot's Associate programme, passive ranging RFI, electronic maintenance manuals and an advanced flight control system. Plans for full authority fly-by-wirehave been dropped on cost grounds. The Block 3 programme has secured $600 million of funding in 2006-11 diverted from the Boeing Sikorsky RAH-66 Comanche, but more money is needed to begin development work in 2005.

Source: Flight International