RAF designation: Sentinel R. Mk 1

TYPE: Airborne ground surveillance system.

PROGRAMME: On 15 June 1999 Raytheon Systems Limited was chosen as the preferred bidder for the UK Ministry of Defence's Airborne Stand-off Radar (ASTOR) programme, for which five Global Express airframes are being modified by Bombardier's Belfast division to provide the airborne platform for radar and communications systems. Contract value £800 million (1999). Preliminary Design Review (PDR) scheduled for completion in March 2001; 200-hour flight test programme of an aerodynamically representative airframe, modified from Global Express prototype C-FBGX, began on 3 August 2001, leading to Critical Design Review (CDR) and design freeze in fourth quarter 2002. First production airframe (C-GJR6/ZJ690) delivered 7 February 2002 to Raytheon Systems Limited at Greenville, Texas, for airframe modification and systems integration, being followed in 2003 by flight tests and operational acceptance trials before delivery to UK Ministry of Defence in 2004. Second production airframe (C-FZVM/ZJ691) delivered to Hawarden, UK, on 29 January 2003. Known as ASTOR until 'Sentinel' name assigned June 2003. In-service date is 2005, with aircraft based at RAF Waddington, Lincolnshire and operated by No. 5 Squadron. Final delivery to RAF due in 2007.