Stewart Penney/LONDON
The UK's selection of the Meteor as its beyond visual range air-to-air missile (BVRAAM) to arm its Eurofighters has ended a long-running hard-fought competition and opens the way for Europe to develop its own medium-range weapon. Raytheon and the US armed forces, however, will continue to develop the AIM-120 advanced medium range air-to-air missile (AMRAAM).
Concern that Russia's Vympel, probably with Chinese money, will continue to develop longer range, more capable versions of the RVV-AE/R-77 (AA-12 Adder) means that the West will be forced to continue developing its beyond visual range air-to-air weapons to maintain the air superiority - if not supremacy. Key requirements are a large no-escape zone, and the ability to manoeuvre hard during the final engagement, even if the motor has burnt out.
Meteor is heralded as the missile which will allow a consolidated European industry to rival Raytheon as the world's biggest missile company. Team Meteor includes the Anglo-French Matra BAe Dynamics (MBD), the Anglo-Italian Alenia Marconi Systems (AMS), Germany's LFK, Spain's Casa and Saab of Sweden. All are to become part of "New MBD", either as core constituents of the new company or through parent company shareholdings.
But a final Meteor contract is some way off and the UK has stipulated a range of crucial milestones which must be met or the programme will be cancelled with MBD expected to repay development funding. UK defence secretary Geoff Hoon said during his May announcement that the "tightly defined" contractual breakpoints would be linked to the ramjet propulsion, guidance system, datalinks and electronic countermeasures. These are to be demonstrated and evaluated by the UK's Defence Evaluation and Research Agency, acting as an independent auditor. The UK will lead the programme, the contract will be let under UK law and the UK will contribute the bulk of the funding, around £800 million-£1 billion ($1.2-1.8 billion), for development and missile procurement.
Before Meteor enters service, MBD has to agree a contract not only with its industrial partners but also six governments. In-service date is set for around the end of this decade, and in the meantime UK Eurofighters - for which Meteor is being procured - will be armed with AMRAAM, for which a £200 million, 400-missile order is to be placed with Raytheon.
Ramjet propulsion
The most obvious difference between Meteor and AMRAAM is the former's ramjet propulsion system, distinguishable by the intakes on the missile body. MBD's missile will be equipped with a Bayern Chemie/Royal Ordnance variable-flow ducted ramjet. This will give the weapon the necessary kinematic performance and 100km (60 miles)-plus range, MBD believes. The ramjet can be throttled, which improves the kinematics, the company says. The ramjet is fed with air from intakes on the lower side of the missile which can become blanked out during hard manoeuvring. To aid re-lighting the motor in such circumstances, an MBD source says the solid fuel propellant produces a "hot fuel-rich gas that ignites automatically when it meets air". A sustain charge continues to burn, eliminating the need for a flame-out/relight mechanism.
Meanwhile, Raytheon will continue to develop the AIM-120 AMRAAM as the US forces' principal long-range missile for the foreseeable future and is likely to take a different approach. A Raytheon source says: "I would envision that we will continue to look at increased kinematics and range." The current offering - the AIM-120C5 - has a 127mm (5inch) longer fuel section as part of its dual pulse motor, which was offered to the UK as part of Raytheon's bid. The source predicts that AMRAAM will not be equipped with a ramjet, as its bulk and shape can limit a missile's manoeuvrability. The revised AMRAAM propulsion section is a result of the US approach of continual missile developments via a series of P³Is. This feeds off a research and development road map for all crucial missile elements - including airframe materials and aerodynamics as well as seeker, propulsion system, fuel, control system, fuze and warhead. AMRAAM entered full service in the 1990s and a phase three P³I is ongoing for deliveries from 2004 with phase four being planned.
AMRAAM and Meteor use active-radar seekers. Meteor's sensor is a development of the Alenia Marconi Systems seeker used in the Aster naval surface-to-air missile. The antenna mechanism is being modified for increased roll rates while the transmitter and central processor will be new. Thomson-CSF will also work on the seeker.
Like the propulsion system, AMRAAM's seeker will be developed as part of the P³I process. The electronics processing the seeker data have been updated already, taking advantage of the continual gain in computing capability. The number of electronics boards have been reduced and additional capabilities, including enhanced electronic counter-countermeasures - the ability to defeat anti-missile jamming - have been introduced.
Consideration has been given to using active-array radars in missiles, but a Raytheon source suggests such radars are unlikely to find widespread missile seeker use in the short term because of heating problems with the active array, which imposes a thermal management constraint on the design. New battery technology may also be needed to supply the power for each module in the active array. The transmit/receive complexity of such arrays makes them expensive for "one mission" systems.
Crucial datalink
Missile radars cannot normally detect targets at a weapon's range extreme, so datalinks are crucial for updating the missile during the early stages of flight. MBD's datalink team is led by BAESystems. The advantage is that the company is the prime contractor for Eurofighter's ECR90 radar, giving the datalink team a head start in designing a link that will allow the aircraft to communicate with the missile. Ericsson, which builds the Saab Gripen's PS-05 radar, is also a member of the team. MBD says Meteor will also be compatible with AMRAAM-style datalink information.
In the USA, co-operative engagement using data from diverse platforms - which could be surface, land, air or space - feeds updated information into a combined air picture and updates the missile during its flight. This capability with AMRAAM has already been demonstrated during a US Army Space and Missile Command test in April this year. During the so-called forward pass trial, a JLENS (Joint Land Attack Cruise Missile Defense Elevated Netted Sensor) radar suspended beneath an aerostat passed targeting information to an AMRAAM which destroyed a manoeuvring cruise missile type target. The missile was ground launched over the horizon from a HUMRAAM- a jeep mounted, AMRAAM-based surface-to-air missile system - against the target which was outside the HUMRAAM's organic sensor picture. The JLENS tracked the target and fed mid-course guidance data to the AMRAAM.
Source: Flight International