India's ASTRA BVRAAM

The Astra missile programme is headed by the Defence Research & Development Organisation (DRDO). The goal of this programme is to provide the Indian Air Force (IAF) with an indigenously-designed beyond visual range air-to-air missile (BVRAAM) to equip the IAF's Mirage 2000, MiG-29, Su-30MKI and the future Light Combat Aircraft (LCA). A model of the Astra was first shown to the public at Aero India '98. On 25 July 2001 in Indian Parliament, then-incumbent Defence Minister Jaswant Singh said that a feasibility study for the Astra has commenced, after the completion of which a project for development of the Astra is planned to be undertaken. Development of this missile is likely to take about seven to eight years. Unconfirmed reports state that the first ground-launched ballistic tests of the Astra airframe are planned for 2003. The Mirage 2000H has been designated as the first potential platform for the Astra when the weapon enters service at the end of this decade.

The Astra missile uses a terminal active radar-seeker to find targets and a mid-course internal guidance system with updates, to track targets. The on-board ECCM capability allows it to jam radar signals from an enemy surface-to-air battery, ensuring that the missile is not tracked or shot down. This indigenous missile is intended to have performance characteristics similar to the R-77RVV-AE (AA-12), which currently forms part of the IAF's missile armoury. The missile is 3.8 metres long and is said to be configured like a longer version of the Super 530D, narrower in front of the wings. Astra uses a HTPB solid-fuel propellant and a 15 kg HE (high-explosive) warhead, activated by a proximity fuse. The missile has a maximum speed of Mach 4+ and a maximum altitude of 20 km. The missile can reportedly undertake 40 g turns close to sea level, when attacking a manoeuvring target. Although designed to use a locally-developed solid fuel propellant, DRDO is also looking at rocket/ramjet propulsion to provide greater range and enhanced kinematic performance.

Robert Hewson, editor of Jane's Air Launched Weapons, in a March 2003 issue of Jane's Defence Weekly stated, "The basic Astra design uses a metallic airframe with a long low aspect-ratio wing and a single-stage smokeless rocket motor. After launch, the missile will use a combination of inertial mid-course guidance and/or data-linked targeting updates before it enters its terminal acquisition phase. In a head-on engagement, the Astra will have a maximum range of 80 km. The missile's onboard radio-frequency seeker has been largely designed in India but incorporates a degree of outside assistance, according to DRDO sources. It will have an autonomous homing range of 15 km. The missile's warhead is a pre-fragmented directional unit, fitted with a proximity fuze. A radar fuze already exists for the Astra, but the DRDO is currently working on a new laser fuze. According to the DRDO, the first ground-launched aerodynamic trials of the Astra will begin within the first half of this year. This will be followed by the next phase of controlled in-flight test launches."

Specifications

Length: 3570 mm
Body Diameter: 178 mm
Wing Span: N/A
Launch Weight: 154 kg.
Warhead: 15 kg pre-fragmented directional.
Fuze: Radar Proximity (laser proximity to follow).
Guidance: Inertial midcourse with data-linked updates, active-radar terminal homing.
Propulsion: Solid rocket motor.
Range: 80 km head on, 15 km tail chase.

A model of the medium-range Astra air-to-air missile. The other model in the background is another DRDO creation --> the medium-range Akash surface-to-air missile.

Indian defence scientists have embarked on an ambitious project to develop an active-radar homing (ARH) ASTRA, a beyond visual range (BVR) air-to-air missile (AAM) capable of destroying enemy targets located at ranges up to 80 kilometres. The missile will be able to outturn a 9g target at that distance, which means it should be able to engage a non-manoeuvring target in excess of 100 kilometres. The project will be guided and led by the Hyderabad-based Defence Research and Development Laboratory (DRDL). ASTRA will weigh 150 kg, making it the lightest in its class and thus enjoying a wide range of applications.

Interestingly some advanced countries and multinational corporations have indicated willingness to join hands for the ASTRA project and this should be welcomed to ensure rapid development and Initial Operational Capability (IOC) with the Indian Air Force (IAF) and Indian Navy. In the long run the ASTRA AAM is set to complement the ultra-long-range Ks-172 and long-range RVV-AE (AA-12 Adder) family of BVR AAMs and R-73RDM2 or possibly Python 5 NBVR/WVR (Near Beyond Visual Range/Within Visual Range) AAMs in the IAFs AAM inventory.

The emergence of top quality Phased Array radars in IAF service has made it possible to detect enemy fighter-sized targets at ranges well beyond 100 kilometres. Only high-quality stealth platforms will remain “invisible” at those ranges. The primary concern of the IAF and the ASTRA development team will be of positive identification of enemy targets at those extended ranges. IFF (Identification Friend or Foe) still remains a challenging complication and even while the United States Air Force (USAF) tactics are BVR dominated, very few BVR shots occurred in combat prior to Gulf War I ‘Desert Storm’.

During ‘Operation Desert Storm’ the United States Navy (USN) were disallowed the use of their AIM-54 Phoenix BVR AAMs for IFF at extended ranges, because they lacked two-sources of information. USAF fighters did posses on-board systems to supplement data from Airborne Command Posts (ACP) like E-3B 'Sentry' airborne warning and control system (AWACS) platforms and were allowed to conduct BVR engagements.

Thus since IFF remains a problem because of incorrect and absent returns and "spoofing", AWACS platforms are presently deployed for reconfirmation of enemy airborne targets at extended ranges and in this respect the IAF will naturally be benefited by induction of PHALCON AWACS platforms. No more the fighter pilots need to follow the risky "eyeball/shooter" sequence, where the flight leader comes unacceptably close to the enemy formation for positive identification and passes the data to other fighters. His associates then fire the BVR missiles. In the long term, development of electro-optical seeker technology coupled with on-board threat database will let the missiles themselves determine the legitimacy of the target and this seems to be the logical option. This option should be considered for the ASTRA Project.

ASTRA should also have provisions for the futuristic concept of “Cooperative Fighter Operations” or Mixed Fighter Force Concept (MFFC) that is essential for future BVR engagements and optimum performance and results. Pairs of aircraft need to be data-linked, allowing one to launch the missiles against the targets while it is illuminated by another. In such engagements a fighter like our light combat aircraft (LCA) TEJAS, will be able to impart the greatest kinetic energy to the ASTRA by accelerating up to Mach 2 and then manoeuvring out of the engagement. The illuminator fighter such as the Sukhoi-30MKI with powerful radar capable of performing like a mini-AWACS would remain firmly subsonic keeping a decent distance from the target, and providing either command-guidance updates or illuminating the target. The option for an Imaging Infra-Red (IIR) seeker for ASTRA should remain open, as ARH is effective in one set of conditions and IIR in another. The open choice of different seeker heads also complicates the problems of the adversary.

The propulsion system appears to be a Rocket/Ramjet because of “dimension and weight constraints”. Adopting a Rocket/Ramjet approach has certain limitations. The need for controlled airflow to the ramjet ducts means that the “skid-to-turn” manoeuvring of a conventional rocket-powered missile is not acceptable because it will risk masking an intake. Instead “bank-to-turn” manoeuvring needs to be adopted resulting in a reduced instantaneous turn rate. Thus close cooperation with the European Consortium MBDA, the manufacturer of Meteor high-performance BVR AAM will prove to be beneficial. The protracted delay in IOC of missiles like Trishul, Akash and Nag are partly because of absence of joint-cooperation with an established foreign manufacturing consortium. This mistake should not be repeated during development of ASTRA especially as MBDA now enjoys very close relationship with the Indian defence industries.

MBDA Meteor is capable of engaging air targets autonomously, whether fighters, bombers, transport aircraft, AWACS or cruise missiles by using its active radar seeker by day or night and in all weather or dense EW (Electronic Warfare) environments. Meteor’s solid fuel variable-flow rocket/ramjet propulsion system will ensure a range in excess of 100 km and a speed of more than Mach 4 and high terminal velocity. Even when launched from extreme stand-off ranges, the missile will have the energy in the end game to defeat fast, manoeuvring targets. To ensure total target destruction, the missile is equipped with both proximity and impact fuzes and a fragmentation warhead that is detonated at the optimum point to maximise lethality. Guidance is ISN, two-way datalink and active Ku-band radar seeker. It can receive targeting data after launch from the launching fighter, another fighter, or AWACS platforms. The two-way data-link partially solves the IFF problem at long ranges. Naturally inputs from the Meteor project will benefit ASTRA development immensely. Also the control surfaces of ASTRA need to be folded for installation in internal missile bays of fifth-generation fighters and for self-defence installations as Bomber Defence Missile (BDM) and in internal rotary-launchers of long-range Indian Navy Tupolev-22M3 ‘Backfire-C’ aircraft.

The “primary carrier” of ASTRA BVR AAM is slated to be the indigenous LCA Tejas, which made its first flight on January 4, 2001. During the year 2001 LCA TD-1 made a total of twelve flights split between Wing Commander Rajiv Kothiyal and Wing Commander Raghunath Nambiar. Now along with two TD (Technology Demonstrator) a PV (Prototype Vehicle) mor tests are also being conducting with more PVs to follow. The LCA is slated to attain IOC with the IAF sometime during the year 2007. This can be termed as a remarkable achievement considering a relatively smoother transition from “first-flight” to IOC. The Fly-By-Wire Flight Control System of the LCA has generated great international interest and LCAs low-speed handling and low-altitude manoeuvrability at an early flight-testing stage points to emergence of a formidable fighter.