RELATING AVIATION SERVICE DIFFICULTY REPORTS TO ACCIDENT DATA FOR SAFETY TREND PREDICTION

Commercial aviation fatalities are predicted (Fulwood et al., 'Relatin g aviation service difficulty reports to accident data for safety tren d prediction', BNL Tech. Rpt 63018, March 1996(1)) using linear superp osition of the time-dependent spectra of key aircraft systems' difficu lties reporting in FAA's Service Difficulty Reports (SDR (DOT, FAA, 'F light standards service difficulty program', Order 8010.2, Feb. 22, 19 78, reissued 4:5/14/81 (2))) data base. The fitting coefficients are f ound by a linear regression model (referred to as 'the model') to FAA' s Accident Incident Data System (AIDS (DOT/FAA, 'Aviation standards ac cident/incident data system-AIDS', Users Guide VS ASAS-D-335, July 198 2 (3))) covering 5.5 years beginning January 1990. The model was teste d by dividing the data approximately in half, using the first half to calibrate the model for prediction of the second half. A second test d id the opposite. A third test used the first 60 months of data to pred ict the following 6 months. These tests (Fig. 5) showed good agreement between the model and ADDS data. The deficiency frequency of ATA (Air craft Transportation Association) systems is reported (Table 2). Third -order fitting of the AIDS data was also used for prediction. All meth ods are compared in Fig. 4. The model was deemed superior because it r eflects inspections and may be updated with SDR data from the Internet . The magnitude of the model's fining coefficients indicate systems im portances to the results. (C) 1998. Published by Elsevier Science Limi ted.