Materiales Compuestos En Aviones

Worries about new composite made airplane


Commercial airplane manufacturers have been using composite materials in transport airplane components for decades. But since 2011, new large transport airplane build mostly in composite have started commercial service. This is the case of the Boeing 787, and later the Airbus A350. Some industry observers have raised concerns about the state of thescience underpinning the expanded use of composite materials in commercial transport category airplanes and Aviation Authorities’ (FAA and EASA) preparedness for this transition. European and US Aviation Authorities are taking actions to address safety-related concerns linked to the use of composite structure, and the GAO (Government Accountability Office) has issue a report in October 2011 toraise its concerns.


1 - Increasing use of composite in commercial airplane


Composite materials in transport airplane components are being used for decades. Prior to the mid-1980s, airplane manufacturers used composite materials in transport category airplanes in secondary structures (e.g., wing edges) and control surfaces. In 1988, Airbus introduced the A320, the first airplane inproduction with an all-composite tail section and, in 1995, the Boeing Company introduced the Boeing 777, also with a composite tail section.


Composite materials used in commercial airplanes typically are produced by combining layers of carbon or glass fibers with epoxy.


In recent years, manufacturers have expanded the use of composites to the fuselage and wings because these materialsare typically lighter and more resistant to corrosion than are the metallic materials that have traditionally been used in airplanes.

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Commercial airplane models over time by percentage of composite


The Boeing 787 is the first mostly composite large transport airplane in commercial service. The Boeing 787 is about 50 percent composite by weight (excluding the engines). It will carry210-290 passengers on routes of 7650 NM to 8500 NM.


It will be followed soon by the Airbus A350, having composite material roughly in the same proportion as its Boeing competitor. The A350 Family provides true long-range capability of flying up to 8500 NM, with seating capacities from 250 to 400-plus passengers.


2 - Who is responsible for the safety of composite structure


Theresponsibility of the safety of an airplane, and subsequently of the safety of composite structure, is shared between three parties:


• The Airworthiness Authorities (e.g: FAA in US, EASA in Europe) are responsible for setting the certification standard and certifying that the airplane manufacturers and parts suppliers meet their standards. They also conduct periodic inspections ofmanufacturing facilities to ensure continued compliance with regulations, and oversee airplane repair facilities to ensure they follow the proper maintenance and training procedures.

• The airplane manufacturers are responsible for showing compliance with those regulations and building safe airplanes. They are also developing airplane maintenance programs and repair manuals and providerequested on-site technical assistance.

• The operators are responsible for operating airplane according to Airworthiness Authority rules and the manufacturer approved manuals. This includes performing adequate maintenance action when appropriate. Airplane operators also help maintaining the airworthiness of their airplane fleets by tracking their airplanes’ service history and reportingrelevant repair and incident data to Authorities and the manufacturers.
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Material used in the Boeing 787


3 - Safety concerns with composite structure


Some concerns have been raised related to the use of large proportion of composite on an airplane structure. These concerns mainly originated from the state of the science underpinning the expanded use of composite materials in...