ASTOR, (Airborne Stand-Off Radar), is an advanced, long-range, ground surveillance system, designed and primed by RSL under contract to the UK MoD.

The company was awarded the £800 million ($1.2 billion) contract in December 1999 and the programme draws on Raytheon's considerable capability in advanced surveillance radar and systems integration.

ASTOR provides the Royal Air Force and the British Army with a world class capability within the network-enabled environment and represents a new era in the planning and management of military operations, providing more accurate information and increasing the tempo of the decision making process. The system affords a highly effective 24-hour surveillance and target acquisition capability. It delivers wide-area, all weather surveillance and reconnaissance imagery in near real-time for national, theatre and tactical headquarters.

At the heart of the ASTOR system is a dual mode Synthetic Aperture Radar/Moving Target Indicator (SAR/MTI) sensor. The SAR will provide high-resolution images while the MTI will track the movement of hostile forces: their numbers, direction and speed. The imagery, which can be exploited both on board the aircraft and on the ground, is transmitted by secure data links to ground stations at all levels of the command and control chain. By operating at high altitude, and at considerable stand-off distances, the radar platform is able to remain over safe territory while providing an excellent “look-down” angle of the target area.

The ASTOR radar platform is based on the Bombardier Global Express new-generation business jet. For the UK requirement the system consists of five aircraft, designated as Sentinel R Mk I by the RAF, and eight ground stations – six for tactical purposes and two at higher operational level. The first two Sentinel R1 aircraft are now engaged in their extensive test flight programmes following modification and integration. Work on the first aircraft was undertaken by Raytheon and L-3 Communications at Greenville in Texas while the second aircraft was modified by RSL at its facility at Broughton in North Wales. Work on the third and fourth aircraft is now also well underway at Broughton where the fifth and final aircraft is also located in readiness for modification and integration activity to commence.

The six Tactical Ground Stations (TGS) are mounted on 20 Steyr 6x6 improved medium-mobility load carriers (up to four vehicles form each TGS unit) while the two Operational Level Ground Stations consist of purpose-built transportable 20ft ISO containers. All ground station integration work has been undertaken at Broughton.

ASTOR will be fully interoperable with allied surveillance and reconnaissance systems.

Sentinel will be operated by Number 5 (AC) Squadron based at RAF Waddington, Lincolnshire, which houses squadron headquarters, maintenance, support and training facilities. The new buildings were handed over to the MoD by Raytheon ahead of schedule and training for the first group of students commenced in 2005.

As prime contractor, RSL is responsible for delivering full capability: hardware, software, infrastructure, training and a comprehensive 10 year Contractor Logistic Support package. In addition some 30 other companies across the UK are, or have been, involved in the ASTOR programme as sub-contractors. Design Authority for the system now resides in the UK and RSL has a support team co-located at RAF Waddington which will manage all in-service support issues including modification and post-design support.

Full operational capability of the ASTOR system is scheduled for 2008.

Regular updates on the status of the ASTOR programme may be found by viewing our News Room.