At the Finmeccanica exhibit here at Farnborough (Outside OE2) visitors once again can find Alenia Aermacchi’s M-346 lead-in fighter trainer. At a first glance the aircraft looks the same as that exhibited at previous airshows, but close up it is possible to note some of the differences featured in this first preproduction aircraft, which was rolled out from the Italian group’s assembly line in April. However, many of the significant changes are not visible externally.
The need to reduce the airframe’s weight, improve manufacturing efficiency and streamline maintenance requirements were the main drivers in the shift from the development and demonstration phase of the program to the pre-industrialization stage. Weight-saving has been on the cards from the start as the two prototype M-346s were equipped with the AMX trainer’s landing gear so the aircraft could be flown while the actual gear was being designed and produced with composite content increased from around 12 to 20 percent. In the rear area, some heat-critical components are built of titanium using super plastic forming (SPF) techniques.
The new landing gear isn’t just lighter. Shock-absorber movement and the width of the track have both been extended by around two inches to allow for landings on rougher surfaces and to provide better stability. In response to an Italian air force request, the landing gear can be retracted up to 250 knots and 3-g load factor.
Other parts of the M-346 airframe have also been refined. For instance, the wings now feature a two-spar wingbox, which is lighter than the previous three-spar unit, and the fuselage structure has 10 fewer ribs than the prototypes. The tail fin, which in the two prototypes was made of conventionally machined light alloy spars, ribs and skin, is now composed of a bonded box, and parts count has been decreased from 191 to 52. All of these features, together with the replacement of some other equipment, has resulted in a weight reduction of about 1,100 pounds.
The reduced weight has also allowed an increase in the maximum fuel weight of about 440 pounds providing the aircraft a ferry range of 1,060 nm with
a 10-percent fuel reserve.
The preproduction M-346 actually will weigh nearly 1,500 pounds less than previous prototypes partly as a result of the integration of more advanced flight test instrumentation. However, this will not be included in the actual production aircraft.
As for aerodynamics, the airbrake has been moved forward by almost three feet as part of a process in which the weight reduction measures have also moved the aircraft’s center of gravity forward. The airbrake now can be operated at angles of up to 60 degrees and speeds of up to 300 knots, and can be used throughout the whole flight envelope if the angle is adjusted to prevailing flight conditions.
The canopy has been modified with the central metallic frame dimensions having been reduced to improve visibility for both pilots. The engine throttle has also been adjusted to afford smoother action and improve its ergonomic features.
The preproduction M-346 also features an upgraded avionics suite. To ensure growth capability the aircraft has been provided with a second databus, which will support the integration of systems devoted to a possible light-attack version, such as a radar and a storage management system. It also will allow for features to improve maintainability, such as the health-and-usage monitoring system.
Other new features, such as a helmet-mounted display and a voice command system will also be installed to comply with a request from the Italian air force, which is the program’s launch customer, with 15 aircraft on order. Delivery of the first production aircraft is planned for late 2010. Flight tests conducted by potential customers have also resulted in some improvements to the man-machine interface in the cockpit.
The M-346’s flight control system is being gradually improved, with about one third more of the development work still to be done, according to Alenia Aermacchi. The FCS hardware was improved with the adoption of new and more powerful Selex-Galileo computers, while the more recent software release by Alenia SIA has allowed a further extension of the flight envelope.
A major step forward will be accomplished next fall, when the first prototype will be equipped with an anti-spin parachute to allow safe testing of aircraft maneuverability at high angles of attack. The first step will allow the jet to reach an angle of attack greater than 35 degrees, rising toward the target of 40 degrees as other tests are successfully performed.
The company anticipates passing another major milestone before year-end, that of transitioning into supersonic speed. The release of the final development software is expected in early 2009 and will allow an increase in the roll rate from 180 to 220 degrees per second and in the load factor limit from 6.5g to 8g. The final release will also allow the implementation of the carefree handling mode. As for the maximum load factor, some potential customers (all F-16 users) asked Alenia Aermacchi to explore a possible increase up to +9g, and company engineers believe it can be achieved safely.
A further improvement expected for 2009 is the adoption of a datalink dedicated to the embedded training simulation system. Currently, M-346s are equipped with a system that allows air-to-air simulation (with the F-16 radar and radar warning receiver) and limited air-to-ground simulation (using Republic of Singapore maps), but the datalink will provide full simulation capabilities.
According to company sou-rces, the configuration will be fully frozen around mid-2009, allowing production to begin in time for projected first deliveries the following year. The empty weight of the production aircraft will be about 10,800 pounds, with a training configuration (full fuel capacity and two pilots) of 15,650 pounds.
According to Alenia Aermacchi CEO Carmelo Cosentino, numerous countries have shown interest in the aircraft, including Chile, the U.S., Algeria, Israel, Taiwan and Saudi Arabia. Last year, test pilots from six other prospective client countries (Austria, France, Greece, Poland, Singapore and the United Arab Emirates) flew the M-346.
In May, Boeing and Alenia Aermacchi launched a partnership to jointly market the M-346 and the existing M-311 basic trainer. The major advantage for the Italian company is that Boeing has strong export positions in key export markets such as the Middle East and Asia. It will also be able to provide after-sales support in those regions.
Also in May, Alenia selected CAE as its preferred supplier for M-346 full-mission simulators. The Canadian simulator specialist will begin by developing a flight training device that includes a cockpit replica with a Medallion-6000 image generator and dome display. CAE will work with Italy’s Selex Galileo to develop a full package of simulators and integrated training systems.