Citation

Roberts W. Transp. Res. Rec. 1999; 1662: 10-23.

Copyright

(Copyright © 1999, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

10.3141/1662-02

PMID

unavailable

Abstract

Knowledge gained from fatal accidents improves the safety design of new vehicles and shows the need to control speed, upset, and overspeed in the existing fleet. Of the 13,000 fatal accidents that have been reported since 1970, 99 percent occurred in general aviation (GA). These accidents are examined, and the fundamentals of fatal accidents are defined. In transports, utilization has grown faster than accident rates have fallen. Thus, the number of fatalities has remained roughly constant for 28 years. In GA, however, the reduction in fatal accidents averages less than 3 percent per year. Fearing that the number of fatalities could actually increase, a White House Commission on Aviation Safety challenged engineers in 1996 to reduce the number of fatal accidents by 80 percent. Accomplishments included (a) the concept of amplification of structural loads on close approach to an instability explained in-flightairframe-failure; (b) the establishment of load and speed at the point of failure (c) the finding that the most likely failure occurs slightly above design cruise speed if minimum strength and minimum stiffness were used in design; (d) the correlation of accident rates with structural flexibility and speed; (e) the finding that strong trends at high speed in four variables could not be intuitively separated until a math model of the failure process was created; (f) the finding that the model matched the 10:1 difference in accident rates between GA and transports; and (g) the finding that the model demonstrated that structural stiffness was more important than structural strength.

Language: en