More recently, manufacturers have extended the use of composites to  airframe structures, such as the fuselage and wings. Boeing’s 787 will be the first mostly composite large transport airplane in  commercial service. The 787 is the first large commercial  transport category airplane to use composite materials for much of its  fuselage and wings. As part of the type certification process, FAA evaluates the airplane’s  design for novel features and the applicability of airworthiness standards  to ensure that the novel airplane features comply with applicable  performance standards or safety levels. FAA Followed Its Special Conditions Process in Requiring That Boeing Demonstrate That the 787’s Composite Structures Meet Existing Safety Levels

		FAA Established Special Conditions for Boeing to Demonstrate That the 787’s Composite Airframe Meets Existing Safety Levels

FAA applied 5 special conditions where it determined the applicable  airworthiness regulations did not contain adequate or appropriate safety  standards for design features related to the 787’s composite fuselage and  wings. FAA Followed Its Processes for Developing and Monitoring Special Conditions

On the basis of our review of FAA’s documentation and discussions with  FAA officials about its activities in developing the five special conditions,  we found that FAA followed the special conditions process. In August 2011, FAA issued the type certificate for  the Boeing 787. In some cases, FAA and Boeing  negotiated certain aspects of the compliance approach. Some comments were technical  corrections. We also found  that FAA documented its determination to grant Boeing an equivalent  level of safety finding, providing a description of the technical issues and  Boeing’s plan to demonstrate the composite fuselage would meet the  current level of safety in a manner similar to how it documented the  special conditions determination, although it did not obtain public  comments, which are not required for an equivalent level of safety finding. EASA Also Assessed the Use of Composite Materials in the Boeing 787

		EASA’s Process Is Similar to FAA’s Special Conditions Process

EASA uses a validation process (a form of certification) to issue a type  certificate indicating that U.S.-manufactured airplanes meet European  airworthiness standards. The extent to which EASA relied on FAA to oversee and determine  Boeing’s compliance with EASA’s composite-related review items varied. FAA and Industry Actions May Address Key Safety-Related Concerns, but It Is Too Early to Assess the Adequacy of These Actions

		Key Safety-Related Concerns Identified in Areas Related to Composite Airframe Repair and Maintenance

Through a review of relevant literature and interviews with experts, we  identified and categorized key safety-related concerns into four areas,  namely (1) limited information on the behavior of composite airframe  structures, (2) technical concerns related to the unique properties of  composite materials, (3) limited standardization of composite materials  and repair techniques, and (4) level of training and awareness on  composite materials. None of the experts that we spoke with felt that the concerns they  identified posed extraordinary safety risks or were insurmountable. Appendix I: Objectives, Scope, and Methodology

This report addresses the Federal Aviation Administration’s (FAA) and the  European Aviation Safety Agency’s (EASA) certification of airplanes using  composite materials, specifically the agencies’ processes for developing  special requirements to ensure that Boeing demonstrates the 787  composite fuselage and wings meet current safety levels, and FAA’s  actions to address safety-related concerns associated with repairing and  maintaining composite airplanes identified by literature and stakeholders. We focused on FAA’s and EASA’s actions as they relate to the  certification of the Boeing 787 because it is the first large transport  category airplane for commercial use with a composite airframe structure  to undergo the certification process. Identification of Repair and Maintenance Concerns

To identify the key safety concerns associated with the repair and  maintenance of composite airframe structures in transport airplanes, we  interviewed 11 aviation experts and conducted a literature search and  reviewed 39 documents and FAA technical reports related to the repair  and maintenance of composite airframe structures in transport category  airplanes.
Why GAO Did This Study

Composite materials, made by combining materials such as carbon fibers with epoxy, have been used in airplane components for decades. Although composites are lighter and stronger than most metals, their increasing use in commercial airplane structures such as the fuselage and wings has raised safety concerns. Boeing's 787 is the first mostly composite large commercial transport airplane to undergo the certification process. The Federal Aviation Administration (FAA) and the European Aviation Safety Agency (EASA) certify new airplane designs and evaluate the airworthiness of novel features--like composite structures--against existing safety standards, which are often based on the performance of metallic airplanes. In August 2011, FAA and EASA certified the 787, which is expected to enter commercial service in the fall of 2011. GAO was asked to review FAA's and EASA's certification processes and FAA's oversight of the composite airplanes once they enter service. GAO examined how FAA and EASA assessed the use of composite materials in the Boeing 787 fuselage and wings, and the extent to which FAA has addressed safety-related concerns associated with the repair and maintenance of composite airplanes. GAO reviewed certification documentation, conducted a literature search, discussed repair and maintenance issues with experts, and interviewed FAA and EASA officials and Boeing representatives. GAO is not making recommendations in this report. FAA, EASA, Boeing, and others provided technical comments, which

What GAO Found

GAO found that FAA followed its certification process in assessing the Boeing 787 airplane's composite fuselage and wings against applicable FAA airworthiness standards. FAA applied five special conditions when it found that its airworthiness standards were not adequate to ensure that the composite structures would comply with existing safety levels. These special conditions require Boeing to take additional steps to demonstrate the 787's structures meet current performance standards. FAA also granted Boeing an equivalent level of safety finding when the manufacturer determined it could meet the standard but prove it differently from the method specified in that standard. On the basis of a review of FAA's special condition requirements, Boeing submissions, and discussions with FAA and Boeing officials, GAO found that FAA followed its process by documenting the technical issues related to the design of the composite fuselage and wings, determining the special conditions and equivalent level of safety finding, obtaining public comments on draft special conditions, and monitoring Boeing's compliance with those conditions. EASA also assessed the use of composite materials in the Boeing 787 and relied on FAA to oversee Boeing's compliance in some cases. EASA's process for determining whether its existing airworthiness standards were adequate to ensure the 787's composite fuselage and wings met current levels of safety was similar to FAA's special conditions process and resulted in some additional review items, partly because of differences in their respective standards. On the basis of expert interviews and a review of literature, GAO identified four key safety-related concerns with the repair and maintenance of composites in commercial airplanes--(1) limited information on the behavior of airplane composite structures, (2) technical issues related to the unique properties of composite materials, (3) standardization of repair materials and techniques, and (4) training and awareness. None of the experts believed these concerns posed extraordinary safety risks or were insurmountable. FAA is taking action to help address these concerns identified by GAO related to the repair and maintenance of composite airplane structures. However, until these composite airplanes enter service, it is unclear if these actions will be sufficient.