FLUG REVUE August 2003: Aermacchi M-346 rolls out

AERMACCHI M-346: NEW TRAINER FOR NEW FIGHTERS

By Karl Schwarz

Procurement of new trainers is not exactly among the priorities of air forces around the world. It is therefore no wonder that 2,400 out of the 3,400 advanced trainers currently in service are over 25 years old. Rising operating costs, Aermacchi believes, will therefore make replacement unavoidable over the next few decades. But that is not the only reason for the optimism of these specialists from Venegono Superiore near Milan: present-day trainers are not capable of preparing student pilots for the fighter aircraft of the new generation, such as the Eurofighter, Gripen or Rafale, as Dr. Eligio Trombetta, deputy director of the M-346 programme, explains. What is required is a training that teaches students how to manage complex systems as well as mastery of an extremely agile aircraft that can fly at high angles of attack.

Paris Airport, Terminal 2E

It is precisely to these requirements that Aermacchi has tailored its new M-346 model, the product of studies dating back to the 1980s. At that time the Italians were working with Dassault and Dasa. A contract was then signed ten years ago with the Russian design bureau Yakovlev, which produced a very interesting demonstrator aircraft, the Yak 130D. Under the programme name of Yak/AEM-130, an extensive flight programme was then completed, starting in April 1996, in the course of which the aircraft registered as RA-43120 had two extended sojourns in Venegono Superiore.

Finally the two companies went their separate ways in 1999. Whereas Yakovlev is still working with modest resources on a production version for the Russian market, in January 2000 Aermacchi launched the M-346 programme. Programme manager Massimo Lucchesini recalls, “It was true that Russian engineers only cost $10 per hour, but we had endless discussions about technical details and the requirements of the (Western) market.” Moreover, the Italians did not want to be dependent on uncertain financing by the Russian government.

The new Aermacchi model, which apart from its basic layout has nothing in common with the Yak 130D, emerged on the basis of the jointly developed database. The aim was to offer significantly better training efficiency than today's advanced trainers such as the BAE Hawk, with comparable life cycle costs.

According to Aermacchi, this will be achieved amongst other things by extending the flight envelope. A 42º angle of attack should be possible, more than on many fighters. Another requirement is that there should be a very good thrust-weight ratio of 0.97 with the tanks half full, which, for example, would allow excellent turn rates of up to 14 degrees per second. A climb rate of around two minutes to 30,000ft (9,150m) is also on the cards.

The excellent aerodynamic performance is not least due to the wings with their supercritical profile and the continuously variable camber. At high angles of attack the wing roots, which extend relatively far forward, generate high-energy vortices which are steered past with small deflectors on the control surfaces. All in all, the M-346 will offer aerodynamic properties similar to those found on modern fighter jets.

It goes without saying that the controls are fly-by-wire, and in this case fourfold redundancy has been built in. This allows free programming of the flight characteristics within the framework of the aerodynamic boundaries. According to Dr. Trombetta, Aermacchi is therefore planning to develop two different control laws, one with “tame” handling for the initial phase of training and the other as close as possible to the characteristics of the future operational type.

The cockpit is likewise based on the standard for modern fighter aircraft, with a head-up display (viewing angle 22º x 22º) and three multi-function colour displays (12.7 x 12.7cm), an external stores management system and HOTAS (hands on throttle and stick i.e. the most important switches are located on the control stick and throttle lever).

The MIL-STD 1553 based avionics will enable students to practise weapons delivery and carry out interception exercises with superimposed “virtual” targets. There are even plans to allow the use of a helmet display. If required, a radar can be installed as well.

The powerplant chosen for the M-346 is the F124 from ITEC (Honeywell). The twin-engine design may put up the purchase price, but should pay off in higher safety. The Rubis auxiliary power unit, which can be started in-flight, will also contribute to this. Many systems are redundantly designed. Here, reliability and low operating costs were deemed important.

The compact airframe is constructed largely of aluminium alloys with selective use of carbon fibre panels and control surfaces made out of bonded mental and composite materials. Service life is specified at at least 10,000 flying hours.

The development of the M-346 Aermacchi is the first programme on which Aermacchi has used integrated teams. Some 300 engineers and technicians are working on the design and production of the three prototypes. The first prototype rolled out on 7 June, and the maiden flight is expected to take place in November. The two other aircraft will follow each at an interval of one year, and there will also be another two airframes for fatigue and fracture testing.

In anticipation of the flight test programme, Aermacchi already has various test rigs in operation for the avionics and individual systems (tanks), as well as an “iron bird” with the complete flight control system. A simulator for working on the flight control software is already being heavily used. The three prototypes will undergo some 700 hours of basic testing in the air. Extensive wiring of the prototypes means that 5,000 parameters (4,000 of them in the avionics area) can be recorded.

If everything goes smoothly, Aermacchi will obtain provisional certification for the M-346 by 2006 and full certification by 2007. This would be just in the timeframe of the competition for a Military Flying Training System for the Royal Air Force. The aircraft would naturally also be of interest to the Eurotraining initiative involving 12 European air forces.

Altogether, Aermacchi believes there is a market for 2,300 new advanced trainers over the next 30 years. Of this number, they are hoping to secure 600 sales, although they are not yet able to name any specific customers. Nevertheless there is currently no direct competition, since, as far as the Italians are concerned, the subsonic performance of the KAI T-50 Golden Eagle and EADS Mako put them firmly in the category of light fighters.

Aermacchi needs the M-346 to sell well, as development is expected to cost Euro 500 million. Aermacchi could not find all this money alone, and so the Italian industry ministry is contributing a significant portion in the form of a conditionally repayable loan. Some of the financial risk is being taken on by some of the suppliers. The price tag for the M-346 trainer is expected to be around $15 million. A later possible variant with weapons system for light combat missions will naturally be somewhat more expensive.

From page 54 of FLUG REVUE 8/2003

Last updated 7 July 2003

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