Secular changes in body dimensions of Royal Australian Air Force aircrew (1971-2005)

The aim of this study was to quantify the secular changes in body dimensions of Royal Australian Air Force aircrew. Following corrections for methodological differences, two samples (matched for age and overall body size) of male aircrew measured in 1971 (n = 220) and 2005 (n = 220) were compared across 13 absolute and proportional body dimensions. Changes in means were expressed as standardised effect sizes and changes in distributional characteristics were expressed as the ratio of coefficients of variation and as changes in skew. Small secular increases (standardised effects sizes >0.2) in age-matched aircrew were observed for mass, height, BMI, sitting height, buttock-knee length, waist girth, hip girth and waist:hip ratio, with a small decline observed for head girth. Changes in body dimensions were not independent of changes in overall body size (except for head girth) and were not always uniform across the distribution. These changes in body size have implications for ensuring correct human-machine and human-equipment fit. STATEMENT OF RELEVANCE: There have been small secular changes in body dimensions of RAAF aircrew between 1971 and 2005, although these secular changes have not always been uniform across the distribution. These secular changes in body dimensions have implications for ensuring correct human-machine and human-equipment fit and underscore the need for regular anthropometric surveys.