FLUG REVUE April 2003: Air-to-air missiles for Eurofighter

NEW EUROPEAN AIR-TO-AIR MISSILES FORGE AHEAD

By Karl Schwarz

Even the most agile fighter aircraft equipped with excellent systems is of little use without appropriate weapons. This may be self-evident, but in the past it has been ignored at great cost by several European armed forces. For example, the Luftwaffe's expensive Tornado fighter bombers flew for almost two decades without laser-guided precision bombs.

A similar discrepancy between the Eurofighter as a modern platform and inadequate weapons is at last to be rectified. Moreover, to avoid building in obstacles to possible exports of the weapon system, dependency on American manufacturers is to be avoided. Accordingly, three separate guided weapons programmes have been launched in Europe with an eye to the new fighter aircraft.

The history of these programmes, like that of the aircraft itself, is free neither of vagaries nor of evidently unavoidable delays caused not least by lack of money in the defence budgets of important partner countries, Germany foremost among them. In December and January, however, Eurofighter's two trailblazing air-to-air guided weapons finally overcame the parliamentary hurdles in Berlin.

In Meteor and IRIS-T (Infra-Red Imaging System, Tail/Thrust Vector Controlled) the Luftwaffe's multi-role fighters will be equipped with a set of weapons whose capability bears comparison with US products. The two guided weapons bring with them crucial improvements compared with the presently used AIM-120 AMRAAM and AIM-9 Sidewinder. They constitute a powerful duo that will allow opponents little chance of escape either in tight dogfights or at distances of up to 100km.

The Meteor will cover the long-range requirement. Thanks to the throttleable solid fuel turbo-ramjet, it is likely to significantly surpass the range of AMRAAM and, in particular, it will still have reserves left in the final approach. Launch will be effected in the normal way with a solid-fuel rocket that accelerates the Meteor to Mach 1. Once this has burnt out, two air inlets will open up and high-energy boron-based fuel will be sprayed via a valve into the now empty tubes where, according to manufacturer Bayern-Chemie, stable, controllable combustion will take place. The combustion period can last between 30 seconds and two minutes.

The Meteor, which can travel at up to Mach 4, will guide itself following target designation, although it will also be possible to update the guidance system via a data link to the aircraft. In the final approach, the active radar seeker, which operates in the Ku band, will take over control. This is based on the French MICA system, works with medium and high pulse repetition frequencies and is partly digitally designed. Particular importance will be attached during development to immunity to interference.

Meteor is a joint venture programme led by the MBDA company (Matra BAE Dynamics/Alenia Marconi Systems), which has plants in the United Kingdom, France and Italy. Partner companies include Bayern-Chemie, Inmize of Spain and Saab Bofors Dynamics of Sweden. Thus the participating countries have already being named. The largest share of funding is coming from the United Kingdom, which is bearing 39.6% of the Euro1.86 billion development and procurement costs. Germany reduced its contribution in December 2002 from 21% to 16%, equivalent to Euro155 million for development.

This does not include the order of 600 missiles for delivery from 2008 or integration of Meteor into Eurofighter, which is expected to cost half a billion euros, of which Germany's share is Euro146 million. After Germany, the last partner to sign up, finally gave the go-ahead in December 2002, the contract was signed on 23 December. The missile is not now expected to enter service until the autumn of 2012.

On the other hand 1250 IRIS-T's are to be delivered to the Luftwaffe between 2005 and 2010. Now that the project has been approved by the Defence and Budget Committees of the Bundestag since the end of January, an intergovernmental agreement must be concluded right away with Greece, Italy, Norway, Sweden and Spain. It is hoped that this will be signed in April. The industry production investment contract and the production of a pilot batch of 50 missiles will enter into effect shortly afterwards. The contract for full production should be signed in 2004.

IRIS-T

Germany's costs are stated at Euro 540.5 million. The country will receive the biggest share of the programme, 45%. The remaining workshares have not yet been announced as they depend on individual unit numbers. However, they will be different from the distribution in the development programme, due to the withdrawal of Canada. Canada's place was officially taken up by Spain in November, which has to pay an "admission charge” as well as its share of the production costs. On the industry side, the Sener company has now joined the programme and, amongst other items, will take over responsibility for the control surface adjustment system.

Development work on IRIS-T, which began after a study phase in 1998, is largely complete. Another round of test firings is to be carried out in March/April to verify performance. Previous tests proved very successful apart from problems with the rocket engine which have now been solved: direct hits on Mirach drones were achieved even under taxing conditions such as high angle of attack, jamming and unfavourable relative positioning of the target. The prime contractor BGT (Bodenseewerk Gerätetechnik) stresses particularly how well the flights agree with forecasts based on simulation.

IRIS-T has a far bigger range of application than the AIM-9L Sidewinder. The imaging infrared search head in focal plane array technology, under which a number of heat seekers arranged in series receive the image over a movable mirror, offers five times as much coverage and is said to deliver excellent results against both a difficult background and also state-of-the-art IR countermeasures. Rapid adjustment and squint angles of +/- 90º combined with a helmet-mounted sight provide the optimum conditions for close combat.

The missile gains the extreme agility needed from thrust vectoring control and the special burn profile of the solid propulsion. Aerodynamic control together with the low aspect ratio wings also offer sufficient manoeuvre potential at a great distance.

Not all the Eurofighter countries are participating in the IRIS-T programme. The reasons for this go back a long way, for in the 1980s there were plans for Germany, the United Kingdom and the USA to together develop a family of guided missiles. After this idea was abandoned, the British decided to develop their own Advanced Short Range Air-to-Air Missile (ASRAAM). A contract to the tune of £570 million (Euro850 million) was awarded to the Guided Missiles Division of British Aerospace (now part of MBDA) as long ago as April 1992. The in-service date was originally set at 1998.

However, like many UK armaments programmes, ASRAAM too suffered considerable delays. It was a good three years after the original planned date that the first operational missiles were handed over to the Royal Air Force in January 2002. This was preceded by severe disagreements between the procurement agency DPA and the manufacturer over the issue of whether ASRAAM satisfied the requirements. According to the Ministry of Defence there were still problems with target pick-up, immunity to interference and hit effectiveness in 2001. It was only after a through overhaul of the software that the shortcomings were finally eliminated.

However, ASRAAM is not expected to attain its full capability until further improvements have been implemented by the end of 2003 at the earliest. But already the missile is an order of magnitude better than the AIM-9L, according to the UK Ministry of Defence. First of all the Interdictor Strike (IDS) Tornado F.3 is to be fitted with ASRAAM. Several squadrons are already operational with the new missile, crew training having been completed. Plans to equip the Harriers and Sea Harriers have meanwhile been abandoned, so that the next task is integration with the Eurofighter. Australia is to equip its F-18's with the ASRAAM.

From page 58 of FLUG REVUE 4/2003

Last updated 4 March 2003

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