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Critical composite structures delivered for major aerospace programs

"ITT Corp. reported on Nov. 19 that it delivered its first major composite structural sponson subassemblies for the CH-53K heavy-lift helicopter to Sikorsky Aircraft Corp.; Spirit AeroSystems has completed a mold/cure cycle for one the panels that make up the longest section of the Airbus A350 XWB’s all-carbon fiber fuselage"


ITT Corp. (Salt Lake City, Utah) reported on Nov. 19 that it delivered its first major composite structural sponson subassemblies for the CH-53K heavy-lift helicopter to Sikorsky Aircraft Corp. (a subsidiary of United Technologies Corp., Stratford, Conn.). The delivery is the culmination of nearly three years of advanced design, development, testing and manufacturing activities, according to ITT. The CH-53K is the latest iteration of Sikorsky’s legacy helicopters, used by the U.S. Marine Corps since 1963. The K model, also known as Super Stallion, will offer significantly greater payload capacity than its predecessor and is currently the largest maritime helicopter in the world.


CH-53K 

The sponson assemblies are a significant technology advancement, with composite materials applied to military aircraft that operate in harsh environments. The sponsons, which attach to each side of a helicopter fuselage, house important components, including landing gear, fuel and other mechanical and electrical assemblies, without compromising interior passenger or cargo space. Each sponson is 25 ft/7.6m long by 4 ft/1.2m wide and 5 ft/1.5m high and is designed to be significantly more resilient to environmental conditions, ballistics and in-flight stress while allowing for increased cabin width without a change in vehicle footprint.

To meet the demanding weight, durability and affordability objectives of the CH-53K helicopter program, ITT is employing the latest composite design and manufacturing technologies for these important flight structures, including electronic model control; laser-ply projection; 5-axis computer numerically controlled machining; automated trimming and drilling; and laser and ultrasonic inspection of all subassemblies.

“We’ve brought the best of our composite technology and experience to produce a stronger, more durable and operationally flexible aircraft to help the Marines perform their critical missions,” said Jim Barber, vice president of ITT’s Integrated Structures business area. Production will take place at ITT’s Electronic Systems facility in Salt Lake City, Utah. This delivery supports the first prototype aircraft, with future potential to support 200 aircraft during the life of the program.

On the fixed-wing side, Airbus partner Spirit AeroSystems (Wichita, Kan.) has completed a mold/cure cycle for one the panels that make up the longest section of the Airbus A350 XWB’s all-carbon fiber fuselage. The 19.7m/64-ft long, 77m2/828.8 ft2 center fuselage crown panel was cured at Spirit’s Kinston, N.C., site. In the coming weeks, the panel will undergo trimming, drilling and nondestructive inspection. Another similar production achievement for the A350 XWB was the successful cure of the first forward fuselage section crown panel by Premium Aerotech (Augsburg, Germany), which took place in Nordenham, Germany, in September 2010. The A350 XWB’s baseline model design was frozen in December 2008 and is progressing toward entry into service in 2013, says Airbus.



More A350 XWB parts are underway at Aerolia Aerostructures (Toulouse, France), which announced on Nov. 29 the opening of its new Composites Unit in Méaulte, France, north of Paris. The Composites Unit began production of fuselage and shell unit panels for the A350 XWB nose section on Nov. 30. Representing a total investment of €220 million ($291 million), the 18,000m2 (193,750-ft2) plant includes an automated fiber placement machine and an autoclave with a diameter of 7m/23 ft and an inside length of 14m/46 ft.

Meanwhile, Goodrich Corp. (Charlotte, N.C.) announced on Nov. 23 that it delivered its first thrust reversers for the A350 XWB twinjet. The thrust reversers will be installed on a Rolls-Royce Trent XWB engine to be used in the engine ground test program, which was scheduled for the end of 2010. Goodrich shipped the thrust reversers on Nov. 5 from its aerostructures facility in Chula Vista, Calif., which also was the site of final assembly. The reversers went to the Rolls-Royce facility in Derby, U.K., for initial testing before they were shipped to a Rolls-Royce ground-testing site located at the John C. Stennis Space Center in Mississippi. In 2005, Airbus awarded Goodrich a contract to be the exclusive provider of the nacelles and thrust reversers for the A350 XWB. The contract is valued at $6 billion over 20 years, including original equipment and aftermarket revenues.

Source: Composite world

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