Current study investigated 84General aviation and military helicopter accidents in Taiwan between 1972 and 2014. The probable and latent causes of those accidents were clearly defined, and statistically analyzed by error related paths and Human Factors Analysis and Classification System (HFACS). Results indicated that categories of the higher level had better predicted power (between 4.25% and 24.9%) than categories of the lower levels (with odd ratios between 0.19 and 8.67). Fallible decisions in upper command levels directly affected supervisory practices which created pre-conditions for unsafe acts, impair performance of pilots, and lead to unexpected accidents. By identifying the higher level human errors leading to low level helicopter mishaps, Current study provided a practical suggestion to top managers for a better helicopter operational safety environment. HFACS was a useful tool for accident investigations and accident prevention strategies.