Julian Moxon/PARIS
In December, the first production two-seat Rafale was presented to French defence minister Alain Richard at Dassault Aviation's Bordeaux plant. He used the opportunity to confirm the government's first multi-year order for the Rafale, launching the production programme and the beginning of a new era in French military aviation.
Standing before the onlookers before it took off on a demonstration flight was almost certainly the last of a long line of combat aircraft to be designed, tested and manufactured by Dassault Aviation alone. The Rafale will be around for at least 30 years in various guises, but Dassault's role as the sole supplier of France's fighters is already changing to one in which it works in co-operation with other European manufacturers. The sheer cost of such programmes means that no single nation, apart from the USA, can afford to go it alone.
France's need for a new combat aircraft began to materialise at the end of the 1970s, when planning began for a single type to replace the Mirage F1, Jaguar, Mirage III, Mirage IV reconnaissance version, and the navy's Super Etendard and Crusader. Further ahead, the Mirage 2000 will also need replacing.
In 1980/1 France joined the UK and Germany, and later Italy and Spain, in the European Combat Aircraft (ECA)initiative. An integrated international team was formed, but there was little common ground, although in 1983 the five nations' air forces managed to agree on an outline European Staff Target for a future fighter.
Dassault Aviation's executive vice-president for engineering, research and cooperation, Bruno Revellin-Falcoz, remembers how it became clear that France's requirement was not the same as that of the other four partners. "There were major differences in the aims and targets," he says. The problem centred on the partners' preference for an aircraft having long-range interception as its primary mission to replace their Panavia Tornado ADVs, McDonnell Douglas F-4 Phantoms, and Lockheed F-104 Starfighters. This drove the weight up to around 10t, heavier than the smaller, 9t machine proposed by Dassault Aviation, which was to have multirole air-to-air and air-to-ground capability. "We were also the only country that planned a naval version as well," adds Revellin-Falcoz. France also believed a smaller aircraft, because it would cost less, would attract export sales more readily.
The French Government duly withdrew from the ECA effort in July 1985, leaving the other four to go ahead with the experimental European Aircraft Programme which led to the Eurofighter Typhoon.
France had not been idle during the final stages of the ECA negotiations, Dassault Aviation having been busy preparing its own ACX design, which became the Rafale A prototype. This flew for the first time in 1986 after a design and development programme lasting just 27 months.
The respective designs eventually chosen for the Rafale and Eurofighter reveal clearly their fundamental differences, even though both are based around delta wing/canards.
Dassault, with its long experience in delta wing/canard design, had already demonstrated close-coupling of the canard and wing - a solution rejected by the Eurofighter team. "We believed very strongly that the all-moving canard should be close-coupled aerodynamically to the wing," says Revellin-Falcoz. "First, it meant the canard could be located further rearwards, which, particularly in the two-seat version, would give the rear pilot better visibility for the air-to-ground mission. Second, we wanted to take advantage of the flow induction effect to the delta wing. This gave us more efficiency and better control at low speeds and high angle of attack, which was particularly important for carrier operations."
The design of the intakes was another area where the two sides disagreed. "In our book, a twin-engined configuration means it must be a true twin. In other words, we never want a single engine failure affecting the other engine," says Revellin-Falcoz.
This meant that separate intakes were needed, to preserve entry conditions for each powerplant under all conditions. "We think it is risky to have a chin intake, even though today's engines are so reliable," he adds. The Rafale intakes are 'semi-submerged', which are also "better for reducing the frontal signature."
The landing gear, because of the Rafale's carrier role, would also be different. Catapult-assisted take-offs required a particularly strong mounting, which meant the nosegear had to be attached directly to the fuselage to transmit the loads directly through to the main aircraft structure. "That would not have worked well on a chin intake - the resulting structure would have been extremely complicated," says Revellin-Falcoz.
A major contribution to the Rafale's design came from the work carried out in the mid-1970s on the ACF(Avion de Combat Future) programme. In its earlier stages, the ACF had been a relatively large, twin-engined aircraft, which proved too expensive to develop and was cancelled as the first prototype neared completion. The ACF was therefore downsized and given a single engine - becoming the Mirage 2000, which became (in different versions) the principal air-to-air and air-to-ground fighter for the French air force and, including exports, has clocked up around 600 sales.
Revellin-Falcon points to Dassault's private venture effort on a twin-engined version of the Mirage 2000. The Mirage 4000 incorporated several features which became central to the Rafale's capabilities, including the close-coupled canard, advanced boron composite and graphite epoxy materials and reduced natural stability. The aircraft flew for the first time in 1979, a year after its single-engined stablemate and at the same point that the international ECA programme took shape. "So when we joined the ECA we already had a background knowledge of flight testing these two delta configurations. That gave us a natural lead-in to the Rafale", says Revellin-Falcoz.
The Rafale is designed for air superiority, air defence, ground attack, aerial reconnaissance and maritime missions. The key element enabling such a wide range of missions is the Thomson Detexis RBE2 scanning electronic radar, coupled with the Front Sector Optronics and Spectra self-protection systems. In the cockpit, the pilot is equipped with a Hotas (hand-on-stick-and-throttle) control, a 30¼ x 22¼ Sextant Avionique wide field-of-view holographic head-up display for flying, a 20¼ x 20¼ head-level display for tactical situational awareness and a pair of lateral 127 x 127mm (5 x 5 in) colour displays for system resource management. Sextant, which is the main avionics contractor for the Rafale, also provides its Topsight helmet mounted sight/display for acquisition and rapid target designation and is working on a voice recognition system for future versions.
Thomson-CSF Detexis vice-chairman and chief operating officer Jacques Mijonnet says the key to the Rafale's multirole capability is that "since 1985 the development of all of the Rafale's systems has gone ahead together. We've been an integrated team, working on an integrated system." The team included the pilots from the air force and navy, "who have also been central to development of the operational requirements".
Rafale programme
There are three versions of the Rafale: single and dual-seat for the air force and single seat only for the navy (above). They are being fielded with progressively more capability as system development continues, beginning with the mainly air-to-air standard F1 version and leading to the fully multirole F3 standard.
Of the 13 aircraft ordered to-date, three will be reserved for development of the Rafale's future F2 and F3 standards. Funding for definition and development of the F3 standard has not yet been approved, but the version is planned for service entry in 2006/7.
The remaining 10 F2s will go to the navy to form the first half-flotilla, which will become operational on the new nuclear-powered aircraft carrier Charles de Gaulle in mid-2001.
The F2 standard, which is due to begin deliveries in 2003, introduces a significant air-ground capability, with provision for the Scalp long-range stand-off weapon, and the shorter range A2SM weapon, now in the competitive phase (a decision on who will develop the A2SM is due in mid-2000). The version also introduces the Front Sector Optronics system, multifunction information distribution system data transmission system and various improvements to the radar and self-defence systems. Definition of the F2 standard began in January and will end in the autumn, with the full-scale development contract due to be awarded in spring 2000. For the first time in a major programme, the DGA will award a "global" contract to the major industry partners in which the new standard is precisely defined at the beginning of the programme rather than moving along with it, significantly cutting the time and costs of development.
The 48-aircraft multi-year order (28 firm, 20 options), will all be supplied to F2 standard. Of the firmly ordered aircraft, 15 will be two-seaters, six single-seaters for the air force and seven for the navy. The optioned 20 will provide eight aircraft for the navy plus five single-seaters and seven two-seaters for the air force. Around 60% of the air force machines will be two-seaters.
Uncertain period
The order will end a long period of uncertainty during which the ministry insisted on Dassault achieving programme cost cuts and agreeing that Aerospatiale should take over the government's 46% shareholding in the company. French ministry of defence (DGA) Rafale programme chief Jean-Pierre Cornand says future orders are based on a three-year multi-year basis. Political interference notwithstanding, he says the aim is to provide a production run of 22 aircraft a year, "which means we plan to order 66 aircraft in 2003". The DGA is holding to its original requirement for 294 Rafales, 60 for the navy, 234 for the air force.
Despite having its own electronics arm at the time (Dassault Electronique, which has now become part of Thomson-CSF Detexis) Dassault Aviation has always carried out its own flight control system (FCS)development, both software, and the associated hardware.
"Our philosophy today is the same as that which was taught to us by Marcel Dassault," says Bruno Revellin-Falcoz. "He said that first of all, the safety of the aircraft is linked to the quality of the FCS and second, that it is crucial to the opinion a pilot holds about the aircraft. For that reason, we never let anyone else do it."
Dassault's extensive fly-by-wire (FBW) experience was acquired through earlier programmes such as the vertical take-off version of the Mirage in the mid-1960s (where it was used for roll control), the Mirage III and IV, and Mirage 2000, the latter being the first European aircraft to have a 100% FBW, mainly digital, system. More than 500 Mirage 2000s are flying, having amassed "hundreds of thousands" of flight hours, with no losses due to the FBW system, says Revellin-Falcoz.
The Rafale is equipped with a fully digital FCS that, because it is "basically negative" in stability, provides greater agility than has been seen in any previous Dassault aircraft. Each of the four channels (three self-checking digital and one analogue back-up) is 100% independent. Besides its basic function of imparting stability to a naturally unstable machine, the system provides carefree handling for the pilot by limiting the angle of attack to prevent stalling and limiting roll rate and g loading according to the stores carried. On release of a drop tank, for example, the system automatically adjusts limits and accordingly adjusts the flight envelope. Gust alleviation is also provided up to 800kt (1,480km/h).
Low observability
"Survivability is a basic requirement of any combat aircraft," says Revellin-Falcoz. "And low observability is just one of them. When you design an aircraft you obviously do the best you can for low observability in terms of radar cross section, infrared signature, noise and so on." He adds: "Operationally, you can you can also control the aircraft's trajectory in such a way as to present the minimum angle to the enemy." This refers partly to the Rafale's terrain-following capability (see RBE2 phased array radar description, P92) and partly to the techniques for flying the aircraft developed by the French air force. In the fully developed F3 Rafale, the radar will be capable of terrain following capability at the same time as it scans the sky for potential threats. "We have already demonstrated this," he says, adding that it is a unique feature which gives the Rafale true multirole air-to-air/air-to-ground capability. "No aircraft in the world today or coming soon has this capability", he claims.
The Rafale is also equipped with the Spectra electronic warfare/self-defence system (described on P93). It is this combination of low observability and what Revellin-Falcoz calls "intelligent use of electronic warfare" that is the key to its ability to survive.
He admits that achieving true integration of the system that provide the Rafale's multirole ability is not easy. "But you only have to look at what we've done in the past on the Mirage F1, 2000-5 and now the 2000-9, to believe that Dassault is no stranger to highly complex integration tasks."
Armaments
The Rafale is equipped with 14 hardpoints (13 on the Rafale M), five of which are designed for external tanks and heavy ordnance. Total load capacity is more than 9t. All versions of the aircraft are equipped with the Giat Industries Defa 791 30mm cannon, firing 2,500 rounds per minute.
Its principal air-to-air missile is the Matra BAe Dynamics Mica, equipped with the Dassault Electronique (now Thomson-CSF Detexis) AD4A active electromagnetic seeker, and later the infrared seeker still under development. It is the first true fire-and-forget missile to enter service in France, and the electromagnetic version is already in service aboard Mirage 2000-5s for the French air force and export.
The Mica has four firing modes: long-range ("more than 60km", says Matra BAe Dynamics), multi-target interception (combining inertial guidance, in-flight target updating and infrared or electromagnetic terminal guidance); medium-range, multi-target interception; close combat and self-defence.
Source: Flight International
