The US military is moving ahead with plans to field helium-filled aerostats to help support cruise-missile defences.

A new tri-service project office, called the Joint Aerostat Project Management Office for Cruise Missile Defence is being established under US Army auspices at the Redstone Arsenal in Alabama. The US Navy and US Air Force are also participating.

The aerostat will serve as the airborne platform for advanced radar, able to track and target low-flying cruise missiles. The feasibility of using radar-carrying aerostats against cruise missiles was established by a 1994 Defense Science Board study.

The system will consist of an aerostat, sensor suite and ground station. The sensors will provide real-time targeting information to anti-cruise-missile weapons, such as the PAC-3 missile under development or tactical aircraft including the McDonnell Douglas F-15 and Lockheed Martin F-16 fighters, via the Boeing E-3A airborne-warning and control-system aircraft.

The USAF is already using a string of Loral Defense Systems-Akron 420K aerostats fitted with Lockheed Martin L-88A radar, as part of the Tethered Aerostat Radar System (TARS) for drug interdiction along the US/Mexico border and over the Gulf of Mexico. A 420K system costs $20-$25 million.

Loral will bid for the cruise missile defence project. The 420K, which contains 12,000m3 (420,000ft3) of helium, is viewed as the baseline aerostat for the programme, but company officials may offer an aerostat as large as 42,000m3. The smaller air vehicle can carry a 900kg payload to 15,000ft (4,600m) while the much larger aerostat can support a sensor suite weighing 4,500kg at up to 20,000ft in altitude.

Loral will finalise its bid after evaluating the request for proposals, which is expected to be released in the next four months. Yet to be determined is the number of aerostat systems and the sensor suite required by the Pentagon. A combination of on-board and ground station target-information processing is envisaged.

Industry officials believe that the joint programme office will make multiple awards for the concept demonstrations. Another US company expected to submit a bid is TCOM. A limited initial operational capability is expected in 2001-2.

Loral and Thomson-CSF have agreed to market aerostat systems worldwide. The Target radar - a key segment of the French Horizon helicopter-borne battlefield surveillance system - would fit the 420K aerostat well.

Source: Flight International