Air Platforms

UK to upgrade Sentinel R.1s for maritime operations

28 October 2014

The United Kingdom has five Sentinel R.1 surveillance aircraft, which it plans to upgrade for added maritime capability. (Raytheon)

The United Kingdom is to begin the process of upgrading its fleet of Raytheon Sentinel R.1 Airborne Stand-Off Radar (ASTOR) surveillance aircraft to conduct maritime operations in mid-2015, the government disclosed on 24 October.

Answering questions in the House of Commons, the parliamentary undersecretary of state for defence, Philip Dunne, said that a contract for the development and installation of the maritime-capable software upgrade aboard the Royal Air Force's (RAF's) five aircraft will be signed in spring (Q2) 2015.

In late 2013 Raytheon first touted using the platform as a possible solution to bridge the United Kingdom's maritime patrol capability gap. As the aircraft is already equipped with a DB-110 dual-band (synthetic aperture radar and ground moving-target indicator modes) airborne reconnaissance sensor, the upgrade would largely involve modifying the sensor's software rather than installing new hardware.

This upgrade should enable the Sentinel R.1 to detect surface vessels and potentially submarine periscopes. Additional sensors could be fitted to further boost the platform's maritime surveillance capability.

Dunne did not disclose when work might begin and end, nor did he disclose a potential contract value.

The Sentinel R.1 was originally slated to be retired in 2015 as a result of budget cuts announced in the Strategic Defence and Security Review (SDSR) in 2010, but an impressive showing in Afghanistan and Libya has prompted the Ministry of Defence (MoD) to delay this until 2018.


The news that work to upgrade the Sentinel R.1's maritime capabilities will soon begin follows the disclosure at the Farnborough Airshow in July that the RAF is looking to introduce enhanced capabilities to the surveillance aircraft to turn it into a true multi-mission platform.
However, while reprieving the aircraft and expanding the scope of its mission set might seem like an ideal solution for the MoD to bridge its maritime patrol capability gap, it should be noted that the Sentinel R.1 would be unarmed. It would have no offensive anti-submarine warfare (ASW) or anti-surface vessel warfare (ASuW) capability whatsoever.
Despite this, an upgraded Sentinel R.1 could provide the United Kingdom with a very useful maritime surveillance capability, which could be supplemented by a more advanced (and expensive) ASW/ASuW platform, such as the Boeing P-8A Poseidon.
This combination would enable the MoD to field the full-spectrum maritime patrol capability that it lost with the cancellation of the BAE Systems Nimrod MRA4 in 2010. The 'low-end' Sentinel R.1s could be used for everyday maritime surveillance, saving the 'high-end' P-8A Poseidons for the less common ASW/ASuW and long-range search and rescue missions.

(420 words)