Options for the future delivery of the UK’s Airborne Warning and Control capability are being explored, including upgrades to the current E-3 Sentry fleet, however some industry commentators are arguing for a new aircraft type altogether.
Madeleine Moon, Chair of the Defence Sub-Committee, asked:
“To ask the Secretary of State for Defence, when he plans to run a competition to replace the RAF’s airborne early warning aircraft.”
Guto Bebb, Parliamentary Under-Secretary of State for Defence, answered:
“No decision has been made with regard to the future delivery of the UK’s Airborne Warning and Control capabilities, although a range of options are being explored. I am withholding details of the level of funding allocated for the future delivery of the RAF’s Airborne Warning and Control System as releasing them would prejudice commercial interests.”
The large sums of money allocated to upgrading the E-3D fleet should be used to purchase a more advanced off-the-shelf aircraft, a defence analyst has argued. Justin Bronk, Research Fellow, Airpower and Technology, outlines options for replacing the E-3 fleet in his paper ‘The Future of Air C2 and AEW: E-3 Sentry, Threat Technologies and Future Replacement Options’:
“The RAF’s E-3Ds need a £2-billion CSP both to bring them to rough parity with current US and French standards by the mid-2020s and to stretch the fleet out to 2035 in the process. However, the E-3, even in modernised form, is no longer a cutting-edge ABM&S system in a world where proliferating long-range missile systems and emerging non-Western low-observable fighters can force it to stay hundreds of kilometres from contested airspace, placing a higher premium on BLOS communications capacity rather than onboard sensors.
Even when it is able to operate closer to the battlespace, the AN/APY-1/2 mechanically scanned radar array common to all E-3s has significant inherent limitations in terms of its ability to detect low-observable, very slow moving and hypersonic threats, unlike more modern AESA-equipped AWACS types already in service with the US Navy and various air forces around the world. An AESA-equipped ABM&S platform with improved communications node capabilities, based on a commercial-derivative airframe, seems a logical alternative option which could provide the RAF with a more capable and efficient alternative to extending the life of the E-3D over the next 20 years.
Such an approach would incur programmatic risk and acquisition and integration costs, but the MoD should examine and weigh these against the expensive work required to extend the E-3D with a view to ensuring the RAF has the best capability possible for the next two decades.”
The US designed E-3D Sentry AEW.Mk 1 is an airborne early warning (AEW) and command and control aircraft in British service, but what does that mean?
The Sentry monitors airspace to provide threat detection of adversary aircraft and situational awareness on friendly assets.
Information gathered by the Northrop Grumman APY-2 radar is processed by the mission crew and disseminated via a variety of data links and communication systems. Sentry also has the capability to detect ships, relaying information to maritime aircraft or allied vessels for further investigation. Its electronic support measures equipment enables the E-3D to gather emissions from other radar systems and emitters, enhancing the crew’s understanding of the environment in which it is operating.
Modified with a Westinghouse AN/APY-1 radar system, its antenna covered by a massive rotating radome held over the rear fuselage, the first of two EC-137D prototypes completed its initial flight on February 5, 1972. After an extensive test programme, the E-3A production version entered service in March 1977. Although the type is officially named ‘Sentry’, the USAF designates it E-3 AWACS. Officially designated Sentry AEW.Mk 1 in RAF service, but commonly known as E-3D, the new aircraft differed from the US fleet in its powerplant of more efficient CFM56 engines.
Today the Sentry is fully integrated into the ISTAR Force, yet retains its core competencies of airborne early warning and airspace management. The 2015 Strategic Defence and Security Review called for Sentry to remain in service until 2035.