Australia’s Chance for a Regional Fighter Project

After decades of discussion on the proper form of an aircraft manufacturing industry for Australia (a discussion totally devoid of any statesmanlike vision of the country’s future), it has been decided to pool residual resources in the development of a turboprop trainer for the RAAF. Assuming that the finished product meets the requirement (AFSR 5044), the service will buy 69 of these aircraft, the underlying hope being that exports will follow and the RAAF will be sufficiently impressed to allow the AAC to design the Macchi replacement.

While wishing the basic trainer success, it can be argued that it is wrong to base Australian industry hopes of a growing indigenous development capability solely on the basic trainer programme. It is only realistic to assume that when the prototype flies in February 1985 it will still be minor bugs to be worked out. Production deliveries began in October 1987 and RAAF type approval is scheduled for July 1988, hence it is going to be the late 1980s before the word has got around that the AAC can actually design something that handles the way a trainer should, can manufacture it in a reasonable number of man-hours, and can provide the product support needed to keep the thing flying. In fact, there is more than a possibility that, by the time it sinks in that it would be a good idea to give the Macchi replacement job to the AAC, there will not be time to design anything more than a modest derivative of an existing aircraft.

There is thus a case for the AAC to have a second option for its next project, something that offers experience in more advanced technologies and the possibility of a far longer production run. It is well known that the trainer market has for several years been crowded with competitors, only a handful of which will ever reach economic production numbers. In contrast, the lightweight fighter market seems set for large-scale expansion as more countries suffer cuts in defence spending, and air forces look around for combat aircraft that are not only effective, but also relatively cheap to buy and operate.

The concept of the lightweight supersonic fighter was pioneered by Northrop, which company recognised the potential weight saving to be achieved by the combined benefits of simple, lightweight engines that had originally been developed for missile applications, and 75 kg Sidewinder AAMs, which could achieve a high kill probability by virtue of precise IR-homing. The first aircraft of this new family(the YT-38 and N-156F) flew in 1959, and the production had a clean take-off weight of only 5973 kg, a remarkably low figure for a Mach 1. 4 fighter. The F-5A fulfilled a useful role in providing low cost air combat training for many less wealthy nations, but the concept of a lightweight fighter was ahead of its time. The 1960s were the days of iron bombs and massive radars, and the F-5A could aspire to nothing more than being a short-range clear-weather fighter.

The second generation appeared 10 years later, with first flight of a YF-5B-21 in 1969. The resulting F-5E was not only better powered, but it was also more serious in size and equipment terms. Clean take-off weight had risen to 7000 kg, and equipment options included an Emerson APQ-153 radar. It was still not a long-range multi-role fighter, but it was a cost-effective match for even an F-15 in a close-dogfight. The day of the lightweight fighter had not yet arrived, but it was clearly getting very close.

The third generation arrived with the first flight of the F-20 Tigershark on 30 August 1982, replacing its predecessors’ two J85s with a single F404, and with a clean take-off weight of around 7760 kg. With a General Electric APG-67(V) pulse-Doppler radar, a Honeywell laser-inertial system, and provisions for various forms of electronic warfare equipment, AMRAAM, and smart air-surface weaponry, the F-20 has a genuine multi-role capability. Properly developed and marketed, it may equal or exceed the success of the previous generations (the T-38, F-5A and F-5E series each having sold more than 1000 units).

The time of the lightweight fighter has arrived basically because of the General Electric F404 engine, because there is a new generation of light, high-capability avionics, because there is a growing acceptance of smart weapons (in place of tons of dumb bombs), and because our perception of a lightweight fighter has moved up the scale to an aircraft of 8000 to 10,000 kg.

The credibility of the lightweight fighter concept is shortly to be enhanced by two significant developments. Firstly, the use of advanced composite materials can result in a 20 per cent weight reduction in individual components, hence their large-scale application can produce a far lighter aircraft for a given mission. Secondly, advances in aerodynamics can produce much higher lift coefficients in combat, and hence much smaller wings can be used for a given turning performance. In short, Northrop was perfectly correct in foreseeing in the 1950s a market for lightweight fighters, but it has taken another 30 years for the technology to catch up with the idea and also for us to appreciate the value of small size in a stealth sense). The potential market for a multi-role lightweight fighter could well be far greater than Northrop ever foresaw.

From technological and production aspects, there are sound arguments in favour of Australia becoming involved in an advanced lightweight fighter programme. Combat aircraft have traditionally represented the cutting edge in terms of new materials and manufacturing processes, and industry would undoubtedly learn a great deal from such work. Likewise, this class of fighter is undoubtedly going to sell in far higher numbers than whatever derives from Britain’s ACA, France’s ACX, or America’s, hence there are far better prospects for long production runs.

Australia is far better suited to participation in such a programme than the vast majority of countries with such aspirations. Aside from the fact that English is still the main language of aviation, the Australian industry benefits from being able to work in both Imperial and metric units. Perhaps the most important factor of all is that Australia has infinitely better access to US classified information than any of the nations with an embryo aircraft industry: many reports are released on a ‘NAlO and Australia only’ basis.

The attractions of Australia as a potential partner in a light fighter programme are, of course, not enhanced by the lack of political interest in the manufacturing industry or by the small potential domestic market. However, it can be argued that the F-18 is too expensive an aircraft to risk in simple close support missions and that its cost is better justified in providing air defence for Australian cities and coastal shipping (thus substituting for the RAN’s carriers) and in ultimately replacing the F-111 in the long-range strike and reconnaissance roles. Viewed in this light, there is a rational case for the RAAF to have a lightweight fighter to complement the F-18, and one powered by a similar F404 engine would have special attractions.

There are many countries with which Australia might reach some form of partnership agreement on the development of a lightweight fighter, but the following discussion is limited to the Western Pacific region. In a financial and technological sense, Japan is well equipped to play a leading role in a collaborative fighter venture and has a possible domestic requirement for such an aircraft in the F-1 replacement context. The JASDF has 73 F-1 close support aircraft in service or on order, and it was originally planned to start phasing in a replacement in 1990, but a service life extension programme (SLEP) has now pushed this date back to 1993. Funding for the FSX programme to replace the F-1 is planned to begin in the 1986-87 budget. Since the number of aircraft required is comparatively small, the Japan Defense Agency is studying the possibility of combining the FSX programme with a later one to replace the much heavier, all-weather F-4EJ and F-15J, although the basic requirements are clearly quite different. The JASDF might welcome the idea of a collaborative lightweight fighter programme as a means to avoid a difficult compromise, while Japanese industry (like that in Germany) might welcome collaboration as a means to avoid the formal ban on arms exports.

Although not in the same league as Japan, Indonesia has ambitious plans for the Nurtanio Aircraft Industry and is well worth consideration as a potential partner. The plan for the period 1986-96 envisages an expansion in the workforce from 8500 to 48,000, and a range of new projects, including a trainer to slot between the T-34C and the Hawk, an 80-100 seat transport to follow the CN-235, and a hot-rod fighter for the year 2000. Whether these plans actually mature depends on many factors (including the remaining in office of Nurtanio’s president, Dr Habibie, who is also Minister for Technology), but Indonesia is potentially a wealthy country, and certainly has ambitions for industrial advancement.

Singapore too wishes to develop its existing overhaul facilities to include a modern production line, based on Nair superiority fighter. With almost as many combat aircraft as the RAAF, Singapore must thus rank as another potential partner. If New Zealand keeps its A-4s in service until the 1990s by means of a SLEP or by buying further examples of the type, then this country too would become both a potential market and a manufacturing partner.

Competition

In the event that a regional grouping could be assembled to develop and produce a lightweight fighter for the close support and air superiority roles, the main competition that the new project would face would be America’sF-20, Sweden’sJAS-39, and Israel’s Lavi.

The Northrop F-20 is a perfectly conventional aircraft with a projected unit flyaway cost in the region of $US10. 7 million. The first production model will have the 7710 kg F404 and the 17. 3 sq m wing area of the F-5E. With 2290 kg of internal fuel and a pair of Sidewinders, the take-off weight will be approximately 8345 kg, giving a thrust/weight ratio of 0. 92. However, the ‘numbers aeroplane’ is seen as the F-20C with the 8165 kg ‘Swedish F404’, a 22. 3 sq m wing area, and 2470 kg of internal fuel. Take-off weight with two Sidewinders will be roughly 8570 kg, corresponding to a thrust/ weight ratio of 0. 95. within the existing engine envelope, the F404 can in principle be developed further to a static thrust of 8615 kg, resulting in the F-20E with a thrust/weight ratio in the region of 0. 975.

In essence, the F-20 is a low-risk aircraft that was designed to retain the excellent handling characteristics of its predecessors of the F-5 series. TheF-20C undoubtedly offers a lot of performance, including a maximum speed of Mach 1. 93, a climb rate of 270 m/sec, a time of 2. 2 min to 12,200 m, and a sustained turn rate of 13 deg/sec at Mach 0. 8 and a height of 4600 m. Its equipment options ensure a multi-role capability that would have been inconceivable for earlier generations of lightweight fighters.

If there is any logic in the way that people buy aeroplanes, then Northrop can reasonably hope to sell more than a thousand of this third generation. However, it can also be argued that by the mid-1990s the F-20 will be on the decline (by reference to the historical precedents of the F-5A and F-5E), and that the market will then be ready for something more advanced. Northrop may respond with some conviction that this is an unfair comment, since the F-20C will have relaxed static stability, fly-by-wire controls, and a large percentage of graphite composites in the wing structure. On the other hand the combat aircraft market is governed to a significant extent by considerations of fashion, and by the mid-1990s the conventional configuration of the F-20 may be viewed as a throw-back to the 1960s. Whether this attitude will outweigh such considerations as flying characteristics and cost is, of course, a matter of opinion.

The only other known active project in broadly the same size, weight and performance bracket as the F-20C is the JAS-39, which is being developed in Sweden to supersede the Viggen and remaining Drakens in SAF service. Billed as ‘the first of a new generation of light combat aircraft’, the JAS-39 is designed to weigh only half as much as the Viggen, and cost around 60 per cent as much. Saab-Scania {which company is responsible to the JAS Industry Group for the development and manufacture of the basic aircraft and for overall systems integration) has not yet published precise dimensions, but the aircraft is stated to have an all-up weight of ‘a little more than eight metric tons’, implying a thrust/ weight ratio of around 1. 0 with the 8165 kg Volvo-developedF404J.

The JAS-39 follows the Viggen in having a close-coupled canard layout, but in this case the foreplane is an all-flying surface to assist the elevons in pitch control. Some 30 per cent of the structure will be made in advanced composites. The aircraft will also feature relaxed static stability, fly-by-wire controls, a multi-function pulseDopplerEricsson radar, a wide-angle HUD, and electronic cockpit displays. Following formal approval in mid-1982, the JAS-39 is now proceeding under a development contract that includes five prototypes and an initial production batch of 30 aircraft. First flight is scheduled for 1987, and production deliveries will begin in 1992. The present contract includes not-to-exceed prices for a follow-on batch of 110 aircraft, but Saab expects the eventual total to run to 400 units, since 330 Viggens are being built and around 160 Drakens are still in use. Spending on the JAS-39 programme in the period 1982-2000, including 140 production aircraft, is expected to total $US3. 2 billion in 1981 terms, though Saab has recently indicated an export price of around $USS million in current values.

While the JAS-39 is in roughly the same size bracket as theF-20, the Israel Aircraft Industries’ Lavi is virtually identical in length and span to theF-16, though it is claimed to be significantly lighter, with a basic take-off weight of 9662 kg, and it is powered by the PW1120 cropped-fan derivative of theF100, giving a static thrust of 9350 kg. The nominal thrust/weight ratio is thus 0. 97, and the Lavi has a fuel capacity of 2720 kg. Wing area is 32. 5 sq m.

Like the JAS-39, the Lavi is of close-coupled canard arrangement, but the Israeli aircraft has intake, whereas the Swedes have opted for lateral intakes to minimise debris ingestion. The Lavi will have many composite components, including the wing, vertical tail, all-moving canard, controls surfaces, and various doors and panels. It will also have a wide-angle HUD, an Elta multi-mode radar, and fly-by-wire controls. Maximum speed is estimated at Mach 1. 85.

In considering the technical basis for a new lightweight fighter, there are many advanced concepts that have not been used in the existing designs. These include direct side-force and direct lift control, stealth techniques, conformal weapon carriage, and the use of two-dimensional nozzles for pitch control in short take-off and air combat manoeuvres. Such ideas warrant consideration, their practical advantages being weighed against the additional costs and the risks involved in development.

One new concept that might very well be adopted in a new lightweight fighter is the forward-swept wing, as due for flight testing in April with the Grumman X-29A, a 7900 kg technology demonstrator powered by an F404 engine. This type of wing is claimed to provide improved manoeuvrability with virtually spin-proof handling characteristics, improved low-speed behaviour, and lower stall speeds. Grumman also claims reduced drag, especially at high subsonic speeds. However successful these tests turn out to be, there currently appears to be no suggestion that the X-29A will be developed within the US into an operational aircraft.

It is thus possible that a regional lightweight fighter might be derived from the X-29A, to provide useful development experience in the member countries of the suggested group. It must, however, be emphasised that this particular approach to the attainment of a new type of combat aircraft is only an illustrative example, both in terms of the selection of a technical basis and the choice of potential partners. Most readers may regard the idea as inconceivable, both in financial and technological terms, but it is not really impossible for Australia as part of a multi-national team. Is it really as ridiculous as (for example) cancelling the Melbourne replacement?