At about the same time as the mid-life upgrade of the Indian Air Force’s (IAF) first 50 Su-30MKIs commences, a parallel service life-extension programme (SLEP) involving the IAF’s 120 existing SEPECAT/HAL-built Jaguar IS/IM interdictor/maritime strike aircraft will get underway at Hindustan Aeronautics Ltd’s (HAL) Bangalore-based facilities. This follows a fatigue analysis done by the IAF, which has estimated that the Jaguars could remain operational for another 25 years--till 2030. As part of the SLEP, the Jaguars will be re-engined and re-equipped with a fourth-generation combined cockpit/mission avionics suite along with a related defensive aids suite, all of which will result in the twin-engined Jaguar IS being reborn as a formidable all-weather platform with enhanced technical service life, enhanced weapons carriage capability (especially precision-guided munitions, or PGM), and also a platform capable of undertaking dedicated suppression of enemy air defence (SEAD) missions.
It was in January 2009 that IAF HQ set up a high-level systems evaluation committee whose first task was be to identify a suitable turbofan for the re-engining component of the massive upgrade-cum-SLEP. The engine evaluation-sum-selection process was overseen by K V L Rao, the former Project Director (propulsion systems) of the Defence Research & Development Organisation’s (DRDO) Aeronautical Development Agency (ADA), which is leading the R & D efforts of the Tejas Mk1 and projected Mk2 light combat aircraft (LCA). Bidding for supplying up to 280 turbofans (including 40 spare engines) are UK-based Rolls-Royce and US-based Honeywell Aerospace, with the competitive evaluation process being expected to reach its conclusion by next month. Honeywell is offering its F125IN, a 43.8kN thrust (with afterburning) turbofan, while Rolls-Royce, whose Adour Mk811 (rated at 32.5kN thrust with afterburning) presently powers the Jaguars, has proposed its Adour Mk821 turbofan. Honeywell Aerospace, which first showcased the F125IN at the Aero India 2009 expo in Bangalore, claims that its proposed solution boasts “improved pilot safety, lower maintenance costs and outstanding reliability”, and will result in more than Rs70 billion (US$1.5 billion) in reduced life-cycle costs. The company also proudly labels the F125IN as being a moduler ‘drop-fit’ design that requires no airframe structural modifications, and it had demonstrated this to the IAF in May 2009.
Honeywell Aerospace has also since claimed that the Rolls-Royce/Turbomeca Adour Mk821 will be 83.9kg (185lb) heavier than the current Adour Mk811 engines. The proven and mass-produced F125IN, in comparison, is 267.6kg (590lb) lighter, while offering between 17% and 40% higher thrust, thereby offering the Jaguar a 2-tonne (4,400lb) payload increase. In addition, Honeywell Aerospace asserts that F125IN-powered Jaguars will see a 23% reduction in takeoff distance, faster climb to 6,090 metres (20,000 feet) without utilising afterburners, and 36% extended range due to improved specific fuel consumption and reduced usage of afterburners. Also, the F125IN has been claimed to improve combat survivability by incorporating an auto restart feature while airborne. In contrast, claims Honeywell, the Adour turbofans need to be manually restarted. A dual full authority digital engine control (FADEC) capability with automatic back-up operating modes (like continuous diagnostics/engine monitoring system, and fault detection logic) dramatically reduces pilot workload, according to Honeywell Aerospace. The proven thrust retention of the F125IN (more than 98% after being overhauled) together with future growth potential easily appears to overshadow the Adour Mk821, whose original design is 50 years old, has no margin for growth, asserts Honeywell Aerospace.
Rolls-Royce, on the other hand, claims that its Mk821, which is built on the proven technology of the preceeding Adour engines, offers the lowest-risk re-engining route to the twin benefits of greater thrust and lower life-cycle costs. According to the aero-engine manufacturer, choosing the Mk821 will also offer a high degree of commonality with the Adour Mk951 turbofan that currently powers the BAE Systems/HAL Hawk Mk132 lead-in fighter trainers now in delivery to the IAF. Rolls-Royce too demonstrated the successfull installation and ground-testing of an Adour Mk821 in an ex-Royal Air Force Jaguar at Cosford, UK, in 2009, which was witnessed by an IAF officias. During these tests the Adour Mk821 ran at full reheat and reportedly passed all performance targets set down by the IAF. Rolls-Royce says usage of the ‘drop-fit’ Adour Mk821 will result in 30% reduced life-cycle costs, resulting in life-cycle cost savings to the IAF of more than $2 billion. Thrust ratings over the Jaguar’s existing Adour Mk811 are increased by 20%. The Adour Mk821 also retains 90% commonality with the Adour Mk951 (rated at 6,500lb thrust and featuring 4,000 hours time-between-overhauls and dual FADEC) of the IAF’s Hawk Mk132s, which will result in minimal Adour Mk821-related ground crew training time and reduced acquisitions of new ground engineering hardware.
As far as the to-be-upgraded Jaguar IS’ cockpit/mission avionics go, HAL in February 2009 had revealed a prototype DARIN-3 navigation-and-attack suite, which includes an all-glass cockpit, HOTAS controls, core avionics computer, new-generation stores management system and digital map generator, wide-angle HUD, and an integrated defensive aids suite (IDAS) now being co-developed by the DRDO’s Defence Avionics Research Establishment (DARE) and Cassidian (formerly EADS Defence Electronics). The IDAS will include a radar/laser warning receiver, full multi-spectral detection-capable missile approach warning system, EW jammer pod, and possibly a fibre-optic towed-decoy. Once a threat has been detected, located, and identified by the on-board radar warning receiver, a jamming signal will be generated by the towed-decoy by using a techniques generator based on digital-RF-memory (DRFM) components, which will produce a full range of noise and deception signals between 4.5GHz and 18GHz. The RF signal will then be converted into modulated laser pulses and transmitted down the 100 metre-long fibre-optic cable to the decoy, which will contain a transmitter. For engaging in all-weather precision strikes as part of effects-based air operations, the upgraded Jaguar IS will likely be equipped with two pod-mounted sensors: the 196kg EL/M-20600 radar targetting pod (RTP) from Israel Aerospace Industries’ (IAI) ELTA Systems Division, and RAFAEL Advanced Defence Systems’ Litening-3SU laser designator pod. The former integrates synthetic aperture radar (SAR) imaging, ground moving target indication (GMTI) and precision target tracking into a single sensor. The RTP thus provides high-quality radar images of ground targets and terrain from standoff ranges, even through clouds, rain, fog, battlefield smoke and man-made camouflage, thus also catering for immediate post-strike bomb damage assessment (BDA). Also being considered for integration is the RAFAEL-built RecceLite pod.
For undertaking SEAD missions, the upgraded Jaguar IS will be equipped with twin wide-band jammers and up to four high-speed anti-radiation missiles of an as yet undetermined type. Four integrated EW escort jammers-cum-decoy systems are on offer to the IAF from Raytheon, BAE Systems, IAI/ELTA and RAFAEL. Raytheon’s ALQ-184(V)9 comes along with is a scab-fit unit of four ALE-50 expendable towed-decoys that are added to the aft end of the pod. The ALE-50 comprises a launch controller, launcher and towed-decoy. The decoy protects the host aircraft against radar-guided missiles by providing a more attractive target and seducing them away from the aircraft. Technique coordination between the two systems is managed by an advanced correlation processor (ACP). The ACP makes the decision between the ALQ-184(V)9’s and ALE-50’s threat responses in order to employ the most effective counter to the threat. Raytheon is now developing an infra-red (IR) towed-decoy to expand the capability of both ALE-50 and ALQ-184(V)9 to provide equally effective protection against both RF and IR threats. To provide space for the ALE-50 launch controller and four-decoy launcher, the current low-band controller is modernised and made field programmable by conversion of twelve 1970s vintage circuit cards into two 1990s technology circuit cards. The two-card low-band modification improves MTBF to the degree that the addition of ALE-50 LRUs are completely offset and the resultant ALQ-184(V)9’s MTBF is better than the basic pod. BAE Systems, on the other hand, is offering the reusuable ALE-55 fibre-optic towed-decoy along with the ALQ-184(V)9.
IAI/ELTA’s EL/L-8251 jamming pod offers automatic functionality (with minimal pilot intervention), wide spatial coverage, additional internal power (via an integral ram-air turbine), an advanced receiver channel that provides a high degree of time/frequency selectivity to facilitate effective functionality in dense emitter environments, high threat detection sensitivity, quick and reliable threat identification and accurate direction-finding, an advanced exciter that supports fast response times, simultaneous jamming of multiple threats (using independent directional outputs), a wide array of travelling wave tube or solid-state amplifier multi-beam array transmitters that provide highly directional outputs with augmented effective radiated power, an easy-to-programme fast-loading user-defined file generator, full mission event data recording (for operational and maintenance purposes), a mission debriefing capability that makes use of a personal computer-based mission event replay tool, and an integral built-in test capability. RAFAEL’s Sky Shield escort EW jammer comes equipped with solid-state multi-beam array transmitters and digital receivers required for jamming many threats, while simultaneously transmitting sophisticated jamming signals against different threats and in different directions. RAFAEL’s X-Guard active towed-decoy lures the attacking air combat/surface-to-air missiles away from the protected platform by creating an attractive false target signal which diverts the homing missile from the platform. The X-Guard is designed to defeat advanced tracking techniques, including monopulse and look-on receive-only (LORO) techniques. The decoy is retrievable and can be deployed several times during a mission.
A wide range of PGMs are presently being evaluated by the IAF for the upgraded Jaguar IS, including the AASM from SAGEM (belonging to France’s SAFRAN Group), Raytheon’s JSOW, MBDA’s Diamond Back, Israel Military Industries’ (IMI) modular standoff vehicle (MSOV) and Delilah multi-role cruise missile, and Raytheon’s Paveway 4 and IAI’s Griffin-3 laser-guided bombs. Raytheon, meanwhile, is integrating its munitions control unit (MCU) on an IAF Jaguar IS testbed. The MCU is a plug-and-play system that enables integration of modern weapons on legacy aircraft with minimal modifications to aircraft wiring and no changes to the flight and stores management software. Once the MCU is integrated on an aircraft, aircrews can employ both existing standofff PGMs and air combat missiles while using the aircraft’s existing weapons management system. Raytheon began integrating its MCU on the Jaguar IS in the second quarter of 2009 and plans to finish the work in less than 24 months. For self-protection, a wide range of within visual range air combat missiles are available to the IAF, these including RAFAEL’s Python 5 (already on board the Jaguar IM), Raytheon’s AIM-9X, DIEHL/BGT’s Iris-T, and MBDA’s AIM-132 ASRAAM. Of these, though, only MBDA together with its partners Elbit Systems (supplier of the Dash V helmet-mounted sight) and Cobham (provider of the Jaguar overwing missile launcher, or JOWL) has to date succeeded in integrating the AIM-132 ASRAAM with the Jaguar IS.—Prasun K. Sengupta