Typhoon’s E-scan Radar Introduction Months Away

 - July 21, 2020, 8:00 AM
Typhoon trials aircraft IPA5 with the Captor-E radar undergoes tests in an anechoic chamber. (Photo: Eurofighter)

The Eurofighter Typhoon has lagged behind some of its competitors in fielding an Active Electronically Scanned Array (AESA, or E-scan) radar, but the service introduction of the Captor-E AESA radar on the aircraft is now just months away. Captor-E is currently in production for Kuwait, which will receive its first aircraft this year, and under contract for Qatar. Airbus Defence and Space and sensor system supplier Hensoldt has also signed a contract for an AESA radar for retrofit to the German Tranche 2 and 3 and Spanish Tranche 3 Eurofighter fleets.

The effort to produce an AESA radar for Typhoon began in 1993, with the Anglo/French/German AMSAR (Airborne Multi-Mode Solid-State Active-Array Radar) research and development program. Captor-E, as it is known today, owes its origins to the 2002 British and German industry CECAR (Captor E-sCAn Risk reduction) project, which began as a strand of AMSAR. The project team aimed to develop an AESA derivative of the existing Captor, while adding a new AESA antenna to the existing Captor-D "back end," retaining all features and capabilities of the original system.

A CAESAR (Captor AESA Radar) demonstrator flew aboard a UK MoD-operated BAC One-Eleven on February 24, 2006, and later on Eurofighter Development Aircraft DA5 starting May 8, 2007. The Euroradar consortium offered to provide a CAESAR-based AESA solution for the Eurofighter, but it became clear that a fixed antenna would be handicapped by a more limited scan in azimuth, and by reduced range at the edges of azimuth coverage. To overcome the deficiency, Euroradar explored a number of "moving AESA" designs, using a single or double swashplate repositioner to provide much wider scan limits, and developed CAPTOR-E using just such a system.

Plans originally called for the incorporation of an AESA radar on all Tranche 3 Eurofighters, and they were built with structural provision for a heavier AESA antenna, together with improved cooling and increased electrical power. The Eurofighter E-scan program was not accorded a high priority, however, not least because the mechanically scanned (M-scan) Captor demonstrated such impressive operational capabilities.

Competing visions of a Typhoon AESA led to further delay, but in 2012 Eurofighter GmbH established an AESA radar roadmap, with several versions of the basic Captor-E to meet different customer requirements. Work on Captor-E began using industry funding, and an initial radar was fitted to the UK Typhoon test aircraft, IPA5 (ZJ700) in time to be shown on static display at the 2014 Farnborough air show.

Eurofighter GmbH and the NATO Eurofighter and Tornado Management Agency (NETMA) signed a €1 billion contract to develop the electronically scanned Captor-E radar on November 19, 2014, and work accelerated after Eurofighter and Finmeccanica (now Leonardo) signed an $8.7 billion contract with Kuwait for the delivery of 28 AESA-equipped aircraft in April 2016, with Qatar then signing a contract with the UK for 24 aircraft in December 2017.

Leonardo led the development of Captor-E within the four-nation Euroradar consortium (Leonardo in the UK and Italy, Hensoldt in Germany, and Indra in Spain) and acted as the design authority for the radar, while BAE Systems took equipment design responsibility, integrating the radar onto the Typhoon aircraft. The AESA radar, in Radar 1+ (now known as Mk0) form, is being introduced to the Typhoon as part of the Phase 3B Enhancements (P3Eb) program.

Flight trials began on July 8, 2016, using IPA5 and, from September 2016, IPA8—a German Tranche 3 Eurofighter. From December 23, 2019, the two aircraft were joined by the first Typhoon in Kuwait Air Force configuration—Instrumented Series Production Aircraft 6. Between March 3 and 27 ISPA6 conducted the so-called “E-scan XCR#1” flight test campaign using other Typhoons as radar targets. That completed E-scan entry-into-service flight tests and the overall P3Eb flight test campaign, readying the way for deliveries to Kuwait.

Flight testing confirmed the tactical advantage conferred by the radar’s repositioner, which gives a field of regard 50 percent wider than that provided by conventional fixed E-scan antenna systems. ISPA6 has continued flight testing to refine the radar’s ECCM (electronic counter-countermeasures) capabilities and to conduct final E-scan software release certification flights.

Plans originally called for the “four-nation” version of Captor-E for the original partners to use the same hardware as the export standard Radar 1+, but with additional documentation and performance data to satisfy the four-nation requirements set down by NETMA. However, when Hensoldt recently announced that it had won a contract to develop and produce a new AESA radar for retrofit to the in-service German and Spanish Eurofighter fleets, it revealed that plans had changed.

The aircraft will initially be fitted with the same Mk0 radar as that supplied to Kuwait and Qatar, but the radars will subsequently be upgraded to Mk1 standards with a new digital multi-channel receiver and new transmitter/receiver modules (TRMs), which will be developed under the new €1.5 billion contract. Hensoldt will be the design authority for the new German Mk1 E-scan radar, while Airbus will carry equipment design responsibility. Leonardo will provide the necessary support to enable Hensoldt to assume its role and will continue to provide the processor for the new German radar, which will be assembled at Ulm in Germany, rather than at Leonardo’s Crewe Toll factory in Edinburgh.

No decision has come on which radar will be fitted to the 38 new-build Eurofighters sought under Germany’s Quadriga program, nor for any additional aircraft acquired to replace German Tornados. Germany has previously indicated an interest in the so-called Radar 2 version of Captor-E under development for the UK Royal Air Force and whose features include an expanded and enhanced electronic attack capability, and which Leonardo is developing for service from around the mid-2020s.

Radar Two is expected to be an incrementally improved version of Captor-E, almost certainly with a different antenna. The new antenna will still incorporate a repositioner, but might not have embedded IFF, which could make it harder to use the array as a means of communicating with other aircraft. Radar 2 would have maximum commonality with Radar 1+ in its other hardware and operating interfaces.

Euroradar has said very little about Radar 2, or the EAP and Bright Adder demonstrator programs that preceded it, partly due to secrecy surrounding the British-led program and Hensoldt’s sensitivities (Ulm is developing the Mk1 radar) as well as to avoid denting sales of the current Radar 1+. Although Radar 2 remains some years away from service, it is, according to one program insider, “a real thing, happening very soon, and it’s going to be transformational for Typhoon.”