Closer to the report's subject, the FAA has funded aviation safety research programs that support its certification and regulation processes. Subjects include fire safety, crashworthiness, and aging aircraft. Some of the research was the result of collaboration with universities and aviation manufacturers.
The GAO report finds that the FAA correctly developed special conditions when it found that existing airworthiness regulations could not adequately evaluate the safety of the 787's composite fuselage and wings. Two of these special conditions concerned occupant safety in the event of a crash, and three looked at whether the fuel tank structure was sound enough to prevent fuel leakage or ignition.
Like the FAA, the EASA created special conditions associated with the safety of the 787's composite airframe to address gaps in its own existing airworthiness standards. EASA review items focused on fire resistance, fuel tank protection, crashworthiness, fatigue and damage tolerance, and structural integrity. (See: GAO Raises Concerns About Boeing 787 Dreamliner Composite Repairs.)
Aside from the certification process, the FAA also plays a major role in ensuring the continued safety of in-service aircraft, not only after things go wrong. The GAO report's key concern is what happens when these mostly-composite airplanes, which will include not only Boeing's 787 but also the Airbus 350, are in service and being monitored for repair and maintenance.
According to one study cited by the report, as many as 60 unique materials are used for repairs of composites, while traditional metal repairs require only a dozen or so. The report notes the limited standardization of repair and maintenance techniques for composites. It cites as causes for this not only a lack of experience to date, but also the numerous materials and their different behaviors when damaged, as well as the lack of data due to the proprietary nature of the materials' construction.
In the test industry, fixtures for testing airframes made of composites are manufactured by several companies. German test equipment manufacturer Zwick Roell AG, for example, notes an increase in requests for fixtures and software aimed at composites, including fiber-reinforced types. The company provides systems for compression after impact (CAI) tests and for testing elevated temperature and humidity. Speaking at the company's testEXPO Materials Testing Forum, Zwick CEO Dr. Jan Stefan Roell said that both Boeing and Airbus use the CAI test.
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