Lockheed Martin, Northrop Grumman and Raytheon have been selected by the US Army to undertake concept exploration of an Airborne Common Sensor (ACS) aircraft.

Up to 40 ACS aircraft would replace around 60 Raytheon RC-12 Guardrail and RC-12G Crazy Horse and de Havilland RC-7B Airborne Reconnaissance Low surveillance aircraft used for corps-level intelligence, surveillance and target acquisition. The $2 billion programme may involve both long-range/high-endurance manned aircraft and unmanned air vehicles.

Each team receives $4 million for the 18-month concept exploration phase. Raytheon's team includes SAIC and Motorola, while Northrop Grumman has linked with TRW.

One contractor will be selected for programme definition work lasting 24 months and a 48-month engineering and manufacturing development phase. Initial ACS fielding is scheduled for 2009.

During concept exploration, the three teams will develop recommendations for the sensor suite, datalinks, ground processing architecture and the aircraft. They will consider total ownership costs and undertake virtual prototyping.

ACS will combine signals and imagery intelligence systems with moving target indicator/synthetic aperture radar capabilities. An open architecture system will allow for simpler sensor upgrades.

The aircraft may not be determined until next year, but US Army officials say that the new airborne platforms will routinely operate above 20,000ft (6,060m) and have much greater endurance than those being replaced.

A turboprop is favourite, for which candidates are: the Lockheed Martin Alenia Tactical Transport Systems C-27J, CASA CN235 and C295, and de Havilland Dash 8.

Source: Flight International