The aluminum and titanium investment casting specialist TITAL is going to produce for the Chinese aircraft manufacturer COMAC. The twin-jet aircraft COMAC C919 is the second passenger aircraft entirely developed in the People's Republic of China. The C919 aircraft is a completely new design. The aircraft, produced by the Commercial Aircraft Corporation of China (COMAC), shall see its first flight in 2015. With the C919 COMAC wants to offer an alternative to Boeing 737 and Airbus 320 for short and medium-haul flights, clearly focusing on Chinese airlines. COMAC has orders for 430 aircraft.

Meanwhile TITAL secured firm orders to supply 80 different parts made from aluminum and titanium investment casting. These orders also cover the so-called Hinge Arm, the connecting element or hinge between the fuselage and the passenger door.

COMAC's designers first thought of a milled part as the solution for this Hinge Arm. But following extensive consulting and advice through TITAL's investment casting specialists, COMAC opted for an aluminum investment cast hinge arm. This was the only way to reach the ambitious weight targets.

“Within the technical requirements provided by COMAC, the TITAL engineers optimized the Hinge Arm in terms of topology and then fully used the design flexibility and creative leeway that investment casting offers”, Rainer Sabisch states, engineering manager responsible for COMAC. Thus they reached considerable savings in terms of weight by adapting the design. The casting now weighs 30 per cent less than the initial version machined from a block. The Hinge Arm optimized by TITAL now has a weight of just 8 kg.

Moreover, it was possible to significantly reduce the material and energy consumption for both manufacturing and machining. The C919 is the first aircraft with a hinge arm being an aluminum investment casting and which has also been topologically optimized.

The total purchase order from COMAC, including the Hinge Arm will be developed and produced at TITAL's headquarters in Bestwig where more than 650 people are employed. COMAC holds Tital in high esteem for its competencies and experience in titanium and aluminum investment castings, but also acknowledges the business and technological activities of TITAL at the Chinese site in Nantong. Since 2012 TITAL operates a plant in Nantong, China, where smaller aluminum investment castings are produced for the aerospace industry.