Accession Number : ADA305563

Title :   An Assessment of the Risk Arising from Electrical Effects Associated with the Release of Carbon Fibers From General Aviation Aircraft Fires.

Descriptive Note : Contract rept.,

Corporate Author : LITTLE (ARTHUR D) INC CAMBRIDGE MA

Personal Author(s) : Rosenfield, Donald ; Fiksel, Joseph

PDF Url : ADA305563

Report Date : FEB 1980

Pagination or Media Count : 105

Abstract : A risk assessment was conducted to estimate the potential economic losses through 1993 due to the electrical effects of carbon fibers released from U.S. general aviation aircraft. The usage of carbon fiber (CF) composites in aircraft structures is expected to increase substantially by 1993. Aircraft accidents often involve fires or explosions that could conceivably release minute carbon fibers, which might disperse in the atmosphere, penetrate buildings or enclosures, and cause damaging shorts to electronic equipment. Of an estimated 354 annual general aviation aircraft accidents with fire in the U.S. in 1993, approximately 88 could involve aircraft using carbon fibers. These accidents could result in the release of up to 1.1 kg. per accident, based on forecasts of CF usage through 1993 and experimental tests with burning CF composites. A methodology was developed to compute estimated dollar losses by county and equipment type, using a Poisson model for the incidence of equipment failures. This approach incorporated data on the geographic distribution of potentially vulnerable facilities, as well as the mean CF exposure levels at which various equipment would fail. The results were then statistically aggregated to produce a national risk profile for estimated annual losses in 1993. The expected national loss was $253 per year (1977 dollars), and the likelihood of exceeding $107,000 in annual losses was estimated to be at most one in ten thousand. The sensitivity of these results to major input parameters was investigated, and it was found that under major parameter changes the expected losses would still remain low.

Descriptors :   *CARBON FIBERS, *ELECTRICAL PROPERTIES, *AIRCRAFT FIRES, MATHEMATICAL MODELS, INPUT, AIRCRAFT, RISK, ECONOMICS, EXPOSURE(GENERAL), PARAMETERS, EXPERIMENTAL DESIGN, FACILITIES, VULNERABILITY, BUILDINGS, ELECTRONIC EQUIPMENT, FORECASTING, EXPLOSIONS, TEST METHODS, ESTIMATES, PENETRATION, PROFILES, AIRFRAMES, AVIATION ACCIDENTS, LEVEL(QUANTITY), RELEASE, LOSSES, GEOGRAPHIC DISTRIBUTION, POISSON DENSITY FUNCTIONS, GENERAL AVIATION AIRCRAFT, ACCIDENTS.

Subject Categories : Military Aircraft Operations
      Electrical and Electronic Equipment
      Refractory Fibers

Distribution Statement : APPROVED FOR PUBLIC RELEASE