Air Platforms

UK faces ASTOR capability gap from 2021

18 February 2020

A gap is expected to open in the UK’s airborne surveillance capability in 2021 after the retirement of Sentinel R1, pictured here operating from RAF Akrotiri in Cyprus during Operation ‘Shader’ against Islamic State. Source: Crown Copyright

A gap in the UK's airborne surveillance capability is expected to open in 2021 when the Royal Air Force (RAF) retires its remaining four operational Raytheon Sentinel R1 airborne stand-off radar (ASTOR) aircraft.

The RAF's director for fixed-wing manned aerial surveillance platforms, Group Captain Shaun Gee, revealed in the service's Annual Review 2020 journal published at the beginning of February, "Sentinel is currently scheduled to leave service in 2021, although no alternative source of its unique capability has been identified in that timeframe."

A Ministry of Defence (MoD) spokesman confirmed to Jane's on 13 February that the Sentinel aircraft will be withdrawn from service in March 2021 without being replaced.

"The Strategic Defence and Security Review 2015 confirmed the Sentinel out-of-service date as the end March 2021; there has been no change to this position," said the spokesman. "We are currently assessing a range of potential options that could deliver wide-area surveillance capability. A decision will be taken in due course."

Jane's understands that this has not yet resulted in the start of any procurement process to find a replacement system by the MoD.

A senior RAF source told Jane's , "The UK's requirement for Persistent Wide Area Surveillance (Land) [PWAS(L)] remains extant. There are a range of options that could meet the PWAS(L) capability both in the short term and into the future. The Ministry of Defence is reviewing the capability and solutions available as part of the annual review of the Equipment Programme. The final decision will be reviewed within the Integrated Foreign Policy, Security and Defence Review that will be carried out later this year."

The source said that the Sentinel R1 operating unit, 5 (Army Co-operation) Squadron based at RAF Waddington in Lincolnshire, "remains configured to continue to deliver the PWAS(L) capability on UK, NATO, and coalition operations throughout financial year 2020/21".

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