Comparative Statistical Analysis of Fatal Spin Accidents for Training Gliders

Abstract

Worldwide reports reveal that loss of control (LoC), primarily through spins, accounts for 40-50% of fatal glider crashes. This study aimed to identify if certain two-seat gliders were more prone to fatal crashes involving LoC than others and whether “spin resistance” was correlated with that likelihood. The Aviation Safety Network Wikibase of incident reports was searched for global crashes involving five of the most common two-seat gliders of composite construction. With no globally available risk exposure data, like flights or flight hours, we developed and used Aircraft Service Years from the number of gliders produced and remaining in service. Even using wide uncertainty bounds, the SZD-50 Puchacz glider showed a fatal crash rate several times greater than any other glider in this set. No significant change was observable in the annual rate of fatal crashes over at least three decades. The study calls for a comprehensive global incident database to support safety research and evaluate the effectiveness of safety measures.