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Vital Importance of Maintaining Sentinel R1 Astor Capability By Howard Wheeldon, FRAeS, Wheeldon Strategic Advisory Ltd.






Last week’s much welcomed announcement by Secretary of State for Defence, Gavin Williamson, that the three Royal Navy Batch 1 Offshore Patrol Vessels (HMS Tyne, HMS Mersey and HMS Severn) most of which are currently supporting the Fishery Protection Squadron, are now to be retained for at least another two years in order to bolster UK fishing fleet protection – a decision that I might add will enable to Royal Navy to treble the amount of fishery protection capacity it has and is able to undertake from 200 to 600 days a year – highlights to me some other very important aspects of defence capability that I view we should not only retain long term but also invest in.

Of particular importance in these more troubled geo-political times and one that highlights the absolute need to ensure that the UK maintains sufficient capacity in all forms of critical intelligence, surveillance and target tracking capability, one that in particular stands out to me is that we ensure the Royal Air Force is able to maintain sufficient levels of Airborne Stand-Off Radar (ASTOR) Sentinel R1 capability for the long term.

To that end and following the very sensible decision announced by Secretary of State for Defence last week to retain the Batch One OPV fleet, may I respectfully suggest that a much needed long term extension of Sentinel R1 capability might well be the next obvious step for the Secretary of State for Defence to announce, one that brings the number of available Sentinel R1 aircraft back up to five, that pushes forward the Out-Of-Service Date (OSD) to beyond 2028 where it needs to be and one that also allows mid-life investment to take place on this absolutely vital elements of air power based intelligence capability

In Libya, Iraq, Afghanistan, Syria, Mali and other international deployments since the original five Sentinel R Mk 1 aircraft fleet entered service with the Royal Air Force in 2008, it is difficult to find anyone within the defence community who would argue anything other than that Sentinel has proved to be formidable capability wherever it has been used. With its powerful active electronically-scanned array (AESA) ‘dual mode’ surveillance radar that combines the best in ground moving target indicator (GMTI) and synthetic aperture radar (SAR) imagery, Sentinel which is based at RAF Waddington has provided the UK with unparalleled levels of situational awareness. Sentinel remains a key C4ISTAR (Command, Control, Communication, Computers, Information/Intelligence Surveillance, Target Acquisition and Reconnaissance asset and its role and importance continues to grow.

As a crucial capability Sentinel R1 provides the UK and its allies with unprecedented long-range, wide-area battlefield surveillance, the ability to track armoured formations, conduct strategic reconnaissance and to deliver critical intelligence tasks. The data it collects and imagery it collects is passed in near real-time within minutes to a team of specialist Intelligence, Surveillance, Reconnaissance (ISR) imagery analysts who are able to conduct forensic data analysis in order to generate intelligence products for time-critical dissemination and that enable commanders on the ground to execute current operations and plan future strategies.

Based on a Global Express business jet manufactured by Bombardier, modified and maintained by Raytheon UK, Sentinel R1 aircraft had originally been intended to support conventional war-fighting operations, track armoured formations and conduct strategic reconnaissance tasks. However, such was the proven adaptability and flexibility of Sentinel R1 capability that it has also been able to provide crucial intelligence within humanitarian crisis roles, including mapping and, as another example, used for scaling a flood crisis that hit Southern England in early 2014.

The current Out-Of-Service Date (OSD) for Sentinel R1 (ASTOR) capability is 2021. The 2015 Strategic Defence and Security Review process had also reduced the available number of fully operational aircraft from five down to four. The resulting reduction in Sentinel aircraft and crew capacity has, particularly during a time when the Royal Air Force has found itself deployed on an increasing scale internationally, proved to be extremely difficult and the hope is that the SDSR 2015 position will soon be reversed. Indeed, the loss of just one Sentinel R1 aircraft from the operational fleet has had other more serious implications as well and there is genuine reason to be concerned that, based on the current rate of anticipate mission requirements, No 5(AC) Squadron is no longer able to field or to sustain sufficient capability in order to meet the level of current demands that are placed on it.

Universally regarded within the military and defence community as being one of the most important assets in the UK C4ISTAR inventory, the RAF Waddington based 5(AC) Squadron operated Sentinel R1 (ASTOR) capability remains to me one of the most crucially important asset in the UK ISTAR air power inventory.

Whilst there is clearly a requirement for upgrading Sentinel R1 capability, the vital importance that the asset provides to UK and to our NATO allies requires not only that a long term commitment and extension to the current proposed 2021 OSD of Sentinel R1 capability is made but also that the fifth, currently stored aircraft, should be brought back into the inventory. Doing this would not only provide a sufficient level of Sentinel R1 aircraft capacity to be retained for operational readiness but would also allow scope for upgrading of the internal surveillance radar equipment capability.

CHW (London – 27th November 2018)

Howard Wheeldon FRAeS

Wheeldon Strategic Advisory Ltd,

M: +44 7710 779785

Skype: chwheeldon




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